Caracterización epidemiológica de pacientes con síndrome posterior a resección anterior baja de recto y aproximación de su relación con aspectos demográficos, patológicos y quirúrgicos, en un centro de referencia en Medellín, entre 2016-2022 / Epidemiological characterization of patients with post-low anterior rectal resection syndrome and approximation of its relationship with demographic, pathological, and surgical aspects, in a referral center in Medellin, between 2016-2022

Introducción. El cáncer colorrectal es uno de los tipos de cáncer más comunes y mortales a nivel mundial. Aunque los avances médicos han mejorado el manejo, la cirugía sigue siendo fundamental. La resección anterior baja (RAB) de recto ha ganado relevancia, a pesar de que puede llevar al síndrome de resección anterior baja de recto (LARS, por sus siglas en inglés), afectando la calidad de vida. Métodos. Estudio de corte transversal con intención analítica en un centro de referencia en Medellín, Colombia. Los pacientes con cáncer de recto sometidos a RAB entre enero de 2016 y diciembre de 2022 completaron el cuestionario LARS para evaluar disfunción intestinal. Se evaluaron factores relacionados con la presencia de LARS por medio de un análisis bivariado. Resultados. De 234 pacientes elegibles, 110 (47 %) respondieron la encuesta, predominantemente mujeres (58,2 %). La edad promedio fue 62 años. Dos tercios de los pacientes recibieron neoadyuvancia y el 69 % requirieron ileostomía. La prevalencia de LARS fue 47,3 %. El 80,9 % llevaban más de 12 meses desde la cirugía o el cierre del estoma. Factores estadísticamente significativos asociados a LARS fueron edad mayor de 65 años (p=0,03), estadío patológico avanzado (p=0,02) y requerimiento de estoma (p=0,03). Conclusiones. El LARS afecta a casi la mitad de los pacientes en diferentes etapas posquirúrgicas. El LARS scorees una herramienta práctica para evaluar la función intestinal en el seguimiento del paciente. La prevalencia y los factores de riesgo identificados contribuyen a la comprensión del impacto de la cirugía conservadora del esfínter en la calidad de vida de los pacientes.

Introduction. Colorectal cancer is one of the most common and deadly types of cancer worldwide, with a high incidence of rectal cancer. Although medical advances have improved management, surgery remains crucial. Low anterior resection of the rectum (LAR) has gained significance, despite its potential to lead to low anterior resection syndrome (LARS), affecting quality of life. Methods. A cross-sectional study with analytical intent was conducted at a referral center in Medellín, Colombia. Patients with rectal cancer who underwent LAR between January 2016 and December 2022 completed the LARS questionnaire to assess intestinal dysfunction. Factors related to the presence of LARS were analyzed using bivariate analysis. Results. Of 234 eligible patients, 110 (47%) responded, predominantly women (58.2%). The average age was 62 years. Two-thirds of patients received neoadjuvant therapy and 69% required ileostomy. The prevalence of LARS was 47.3%. 80.9% had been more than 12 months post-surgery or stoma closure. Statistically significant factors associated with LARS included age over 65 years (p=0.03), advanced pathological stage (p=0.02), and stoma requirement (p=0.03). Conclusions. LARS affects almost half of the patients in various post-surgical stages. The LARS score is a practical tool for assessing intestinal function in patient follow-up. The prevalence and risk factors identified contribute to the understanding of the impact of sphincter-conserving surgery on patients' quality of life.

Significance and techniques of pelvic floor reconstruction in laparoscopic low anterior resection for rectal cancer / 国际外科学杂志

The residual pelvic floor cavity formed by laparoscopic low anterior resection for rectal cancer can result in some complications, such as spread of pelvic infection following anastomotic leakage, adhesive intestinal obstruction, and may increase the probability of radiation intestinal injury in case of postoperative radiotherapy. Reconstructing the pelvic floor can prevent the small intestine from entering the residual cavity, reduce the risk of intestinal obstruction and radiation induced intestinal injury; prevent or reduce the occurrence and severity of anastomotic leakage. Reconstructing the pelvic floor can also improve the anal function after low anterior resection to a certain extent and enhance the quality of life of patients. Direct suturing of the pelvic floor peritoneum and pedicled greater omentum flap graft transplantation are currently two commonly used pelvic floor reconstruction methods, which are relatively simple to operate, easy to promote, and worthy of routine application.

Precision diagnosis and standardized treatment of mid-low rectal cancer / 中华消化外科杂志

Colorectal cancer is a major digestive disease in China, with mid-low rectal cancer as the predominant cause. Over the years, Chinese colorectal surgery has made considerable strides, attaining certain successes in clinical diagnosis and treatment, scientific research, and data platform construction. Nevertheless, there is still room for improvement in terms of the accuracy of diagnosis and standardization of treatment. Furthermore, immune checkpoint therapy represented by programmed death-1 have demonstrated initial efficacy in the treatment of mid-low rectal cancer. Further research is required to better understand the relationship and role between immune checkpoint inhibitors and traditional radiotherapy and chemotherapy, and to apply them to precise clinical practice. The authors elaborate on current status of diagnosis and treatment for mid-low rectal cancer in China, in order to provide references for its precission diagnosis and standardized treatment.

Value of dual-layer detector spectral CT quantitative parameters in evaluating treatment response of neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer / 中华放射学杂志

Objective:To explore the value of dual-layer detector spectral CT quantitative parameters in evaluating the treatment response of neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer (LARC).Methods:The study was a cross-sectional study. From May 2021 to March 2023, a total of 52 patients with LARC who received complete nCRT and were pathologically confirmed rectal adenocarcinoma at the Guangdong Province Hospital of Traditional Chinese Medicine were retrospectively enrolled. Each patient underwent spectral CT examination before and after nCRT, including plain scan, arterial phase (AP), and venous phase (VP) scans. According to the tumor regression grade, the patients were divided into the good response ( n=20) and the poor response group ( n=32). Measurements of the primary tumor′s spectral CT parameters, including effective atomic number (Z eff) at plain scan, iodine concentration (IC), CT values of 40 keV and 100 keV virtual monochromatic image (VMI) at dual-enhanced phases, were taken before and after nCRT. Additionally, the normalized iodine concentration (NIC), spectral curve slope (λHU), and the change rate of the above parameters before and after nCRT were calculated. The independent sample t-test or Mann-Whitney U test was used to compare the differences between the two groups. The receiver operating characteristic (ROC) curve was used to assess the efficacy of various metrics in evaluating the tumor treatment response of nCRT. A binary logistic regression analysis of combined parameter results was performed for the parameters with the areas under curve (AUC)>0.75, and the AUC of the combined parameter was evaluated. Results:There were significant differences in NIC AP and λHU VP before nCRT, NIC VP and λHU VP after nCRT, and the change rates of Z eff, NIC AP, NIC VP and λHU AP between the good response group and the poor response group ( P<0.05). The remaining parameters showed no statistically significant difference ( P>0.05). The ROC curve results showed that the AUCs of the above 8 parameters for evaluating tumor treatment response of nCRT were 0.702, 0.655, 0.695, 0.769, 0.738, 0.807, 0.791, and 0.677, respectively. The AUC of the combined model of the three parameters with AUC>0.75 (λHU VP after nCRT, the change rate of NIC AP and NIC VP) was 0.869, with 80.0% sensitivity and 84.4% specificity. Conclusion:The quantitative parameters derived from spectral CT may provide new markers for evaluating the response to nCRT treatment in patients with LARC. The multi-parameter combined model can improve diagnostic efficacy.

Predicting the efficacy of neoadjuvant chemoradiotherapy for locally advanced rectal cancer based on lipid metabolism-related genes / 中华放射肿瘤学杂志

Objective:To investigate the value of lipid metabolism-related genes (LMRG) for predicting the efficacy of neoadjuvant chemoradiotherapy in locally advanced rectal cancer (LARC).Methods:GSE46862, a genome-wide expression data of LARC treated with neoadjuvant radiotherapy, was obtained from the Gene Expression Database, and differential expression analysis was performed to obtain differentially expressed genes. The LMRG were collected from the MSigDB database and intersected with differentially expressed genes to obtain differentially expressed LMRG. Candidate LMRG were identified based on three machine learning algorithms including least absolute shrinkage and selection operator (LASSO), support vector machine - recursive feature elimination (SVM-RFE), and random forest (RF). Functional enrichment analysis was performed using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis to obtain potential function and involved pathways. The accuracy of the candidate LMRG in predicting the efficacy of neoadjuvant chemoradiotherapy for LARC was assessed using receiver operating characteristic (ROC) curve analysis.Results:A total of eight candidate LMRG ( ALOX5AP, FADS2, GALC, PLA2G12A, AGPAT1, AACS, DGKG, ACSBG2) were screened which were mainly involved in biological processes related to lipid metabolism and were involved in the regulation of several important lipid metabolism-related signaling pathways. In addition, these eight candidate LMRG possessed high area under the ROC curve (AUC) for predicting the efficacy of neoadjuvant chemoradiotherapy for LARC. Conclusion:The eight LMRG identified based on three machine learning algorithms had high accuracy in predicting the efficacy of neoadjuvant chemoradiotherapy for LARC, providing clues to identify molecular markers and potential therapeutic targets for preoperative neoadjuvant radiotherapy evaluation of LARC.

Analysis of dose-related factors in small intestine exposure to preoperative radiotherapy for rectal cancer / 中华放射肿瘤学杂志

Objective:To analyze the related factors affecting the dose to the small intestine exposure to preoperative radiotherapy for rectal cancer, aiming to provide reference for alleviating the adverse reactions of radiotherapy for rectal cancer.Methods:Medical record data and radiotherapy plan information of 138 rectal cancer patients who received intensity-modulated arc radiotherapy at Sun Yat-sen University Cancer Center from May 2021 to February 2023 were retrospectively analyzed. Tumor staging, tumor location, gender, age, planned bladder volume, body mass index (BMI), and small intestine irradiation dose volume were subject to Spearman correlation analysis. Further grouping and comparison were conducted based on the correlation results. Independent sample non parametric tests were used for inter group comparison.Results:The main factors related to the small intestine irradiation dose volume were tumor location, gender, planned bladder volume, and BMI. Tumor location was weakly correlated with the small intestine V 5 Gy-V 45 Gy. Gender was weakly correlated with the small intestine V 30 Gy-V 45 Gy. Planned bladder volume was weakly negatively correlated with the small intestine V 20 Gy-V 45 Gy. BMI was weakly negatively correlated with the small intestine V 10 Gy-V 45 Gy. Grouping comparison analysis showed that the small intestine V 5 Gy-V 45 Gy of rectal cancer patients in the low position group was significantly smaller than those in the middle and high position groups (both P<0.05), and there was no significant difference between the middle and high position groups ( P>0.05). Female rectal cancer patients had higher V 30 Gy-V 45 Gy levels than male counterparts ( P<0.05). The small intestine V 20 Gy and V 25 Gy levels in the planned bladder volume <200 ml group were significantly higher than those in the 200-400 ml and >400 ml groups (all P<0.05), whereas there was no difference between the 200-400 ml and >400 ml groups ( P>0.05). The small intestine V 30 Gy-V 45 Gy levels in the 200-400 ml group were significantly lower than those in the <200 ml group, but higher than those in the >400 ml group, and the differences were statistically significant (all P<0.05). Regarding BMI comparison among groups, the small intestine V 15 Gy-V 45 Gy in the low body weight group was significantly higher than those in the other three groups (all P<0.05). There were no significant differences among the normal, overweight, and obese groups (all P>0.05). Conclusion:In preoperative radiotherapy for rectal cancer, more attention should be paid to the dose to the small intestine in patients with middle and high position rectal cancer, female patients, and patients with low body weight.

Effect and safety of preoperative short-course radiotherapy combined with neoadjuvant chemotherapy for elderly patients with locally advanced rectal cancer / 中华老年医学杂志

Objective:To assess the impact of preoperative short-course radiotherapy combined with neoadjuvant chemotherapy on elderly patients with locally advanced rectal cancer after a 2-year follow-up.Methods:In this retrospective cohort study, we included 446 consecutive cases of elderly patients diagnosed and treated for locally advanced rectal cancer(stage Ⅱ-Ⅲ with T3-T4 and/or positive regional lymph nodes)at the First People's Hospital of Shangqiu city from January 2012 to December 2019.The patients were divided into two groups based on the treatment method: an observation group(107 cases)and a control group(339 cases).The patients in the observation group underwent preoperative short-course radiotherapy combined with neoadjuvant chemotherapy.The regimen included short-term radiotherapy(25 Gy over 1 week in 5 fractions)followed by 4 courses of chemotherapy(CAPOX regimen).On the other hand, the control group received concurrent radiotherapy and chemotherapy.The regimen involved 50 Gy over 5 weeks in 25 fractions and concurrent capecitabine chemotherapy.Afterward, total rectal mesentery resection was performed, and postoperatively, 2 and 6 courses of CAPOX chemotherapy were continued.Follow-up was conducted until 31 December 2021, with the primary observation being the disease-free survival(DFS)of patients in both groups.Secondary observations included overall survival(OS)time, lesion progression-free survival(PFS)time, local recurrence rate, and the rate of acute toxicity events.Cox regression analyses were conducted to compare the factors influencing DFS.Results:Among the 446 patients, 303(67.9%)were male and 143(32.1%)were female.The patients in the observation group were found to be younger and had a higher proportion of Eastern Collaborative Oncology Group(ECOG)physical status score 0 compared to the control group(both P<0.05).Additionally, the two groups differed significantly in terms of MRI T stage, N stage, distance from the external anal verge, rectal mesorectal fascial infiltration, pathological stage, and chemotherapy-to-surgery time interval(all P<0.05).Throughout a mean follow-up period of(20.7±3.5)months, there were 76 deaths, 89 distant metastases, and 32 local recurrences.The results of Kaplan-Meier survival analysis revealed that the observation group had a higher disease-free survival(DFS)rate at 2 years of follow-up compared to the control group[73.8%(79/107) vs.68.1%(231/339), Log-rank χ2=2.676, P=0.041].Additionally, the median DFS time was longer in the observation group[19(12, 22)months]compared to the control group[16(11, 19)months]( Z=2.774, P=0.038).Furthermore, the observation group exhibited a significantly longer OS time[26(21, 33)months]compared to the control group[22(18, 14)months]( Z=2.879, P=0.032).However, the median PFS time was similar in both groups[20(14, 25)months vs.16(12, 21)months]( Z=1.545, P=0.123).The incidence of distant metastasis was 18.7%(20/107)in the observation group and 20.4%(69/339)in the control group(Log-rank χ2=0.341, P=0.708), indicating no significant difference.Similarly, there was no significant difference in the risk of local recurrence between the observation group[9.3%(10/107)]and the control group[6.5%(22/339)](Log-rank χ2=0.996, P=0.318).In terms of adverse reactions, there was no statistically significant difference in the incidence of grade≥3 acute toxic reactions between the two groups[19.6%(21/107) vs.12.1%(41/339), Log-rank χ2=1.661, P=0.148].A multifactorial Cox regression analysis revealed that age( HR=0.586, P=0.005), ECOG score( HR=0.721, P=0.028), MRI T-stage( HR=0.605, P=0.008), rectal mesenteric fascial infiltration( HR=1.649, P=0.012), and distance from the external anal verge( HR=0.638, P=0.041)were associated with DFS. Conclusions:The findings indicate that the combination of preoperative short-course radiotherapy and neoadjuvant chemotherapy in elderly patients with locally advanced rectal cancer demonstrates favorable short-term effectiveness and safety.This approach shows promise in improving outcomes for elderly patients with locally advanced rectal cancer.

Clinical application of ileostomy with type B suture / 中华普通外科杂志

Objective:To evaluate safety and efficacy of B-type suture method ileostomy.Methods:Clinical data from 204 patients undergoing laparoscopic low anterior resection combined with protective ileostomy was analysed. Patients were divided into B-type suture ileostomy group ( n=67) and traditional ileostomy group ( n=137). Results:compared with traditional ileostomy group, B-type suture ileostomy group showed statistically significant differences in total operation time [(164±26) min vs. (172±24) min, t=2.229, P=0.027], ileostomy time [(12.7±2.3) min vs. (14.8±2.2) min, t=-6.565, P<0.001], blood loss [(57±20) ml vs. (69±31) ml, t=-2.797, P=0.006], postoperative hospital stay [(10.2±1.9) d vs. (11.8±2.3) d, t=-4.851, P<0.001], specimen incision infection rate (0 vs. 5.1%, P=0.047), postoperative body pain [82 (79-84) vs. 78 (76-80), Z=-5.805, P<0.001], and ileostomy incorporation time [(46±11) min vs. (51±12) min, t=-2.540, P=0.012]. Conclusion:B-type suture ileostomy for prophylactic ileostomy in laparoscopic low anterior resection for rectal cancer is safe and feasible.

Efficacy observation of low-molecular-weight heparin calcium in preventing lower limb deep vein thrombosis after rectal cancer surgery / 肿瘤研究与临床

Objective:To explore the effect of low-molecular-weight heparin calcium in preventing lower limb deep vein thrombosis after rectal cancer surgery.Methods:A retrospective case-control study was conducted. The clinical data of 30 rectal cancer patients with postoperative subcutaneous injection of low-molecular-weight heparin calcium in Beijing Hepingli Hospital from February 2018 to February 2022 were retrospectively analyzed, and 30 patients wearing antithrombotic elastic socks during the same period were selected as controls. In the antithrombotic elastic socks group, the appropriate thrombotic elastic socks were selected according to the actual situation of the patients after operation. Low-molecular-weight heparin calcium group was given subcutaneous injection of low-molecular-weight heparin calcium on the 2nd day after operation. The indexes of coagulation function, situation of postoperative lower limb deep vein thrombosis and perioperative indexes were analyzed.Results:The age of patients in the low-molecular-weight heparin calcium group was (62±12) years old, with 17 women and 13 men. The age of patients in the antithrombotic elastic socks group was (63±1) years old, with 18 women and 12 men. Before prevention, there were no significant differences in platelet count (Plt), activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin time (PT), fibrinogen (FIB), D-dimer (D-D) levels between the two groups (all P > 0.05). After prevention, the FIB and D-D levels of patients in the low-molecular-weight heparin calcium group [(3.3±0.7) g/L and (341±30) μg/L] were lower than those in the antithrombotic elastic socks group [(4.9±0.6) g/L and (428±40) μg/L] ( t values were 9.51 and 9.61, both P < 0.05), but there were no significant differences in Plt, APTT, TT and PT between the two groups (all P > 0.05). The rate of lower limb deep vein thrombosis in the low-molecular-weight heparin calcium group was lower than that in the antithrombotic elastic socks group [6.67% (2/30) vs. 26.67% (8/30), χ2 = 4.32, P < 0.05]. The drainage flow of anterior sacral drainage tube in the two groups decreased gradually on the 1st, 2nd, 3rd and 4th day after surgery, but there were no significant differences between the two groups (all P > 0.05). The thrombosis time of patients in the low-molecular-weight heparin calcium group was longer than that in the antithrombotic elastic socks group [(84±9) h vs. (73±10) h, t = 4.81, P < 0.05], but there were no significant differences between the two groups in the intraoperative bleeding amount, operation time and postoperative hospital stay (all P > 0.05). Conclusions:Compared with antithrombotic elastic socks, low-molecular-weight heparin calcium is more effective and safer in the prevention of lower limb deep vein thrombosis after rectal cancer surgery.

Imaging research progress on complete pathological remission after neoadjuvant therapy for rectal cancer / 中国医师杂志

Rectal cancer is a common malignant tumor in China, with a high mortality rate ranking fifth. Neoadjuvant therapy for rectal cancer can improve patient prognosis and even achieve pathological complete remission (pCR) in some patients, thereby avoiding complications and functional damage caused by radical surgery. Therefore, how to accurately evaluate pCR before surgery is currently a research hotspot. In recent years, new imaging technologies such as endorectal ultrasound, magnetic resonance imaging (MRI), and positron emission computed tomography (PET-CT) have developed rapidly, and imaging evaluation of pCR after neoadjuvant therapy for rectal cancer has achieved good results. This article provides a review of this field, aiming to provide a basis for personalized treatment of rectal cancer patients.

Multi-Parameters Derived from Dual-Layer Spectral-Detector CT in Evaluating the Pathological Tumor Staging of Rectal Adenocarcinoma / 中国医学影像学杂志

Purpose To explore the value of dual-layer spectral detector CT(DLSCT)in evaluating preoperative tumor staging in rectal adenocarcinoma(RA).Materials and Methods A total of 78 patients with pathologically confirmed RA in Guangdong Provincial Hospital of Chinese Medicine from May 2021 to March 2022 were involved in this retrospective study.All the patients underwent plain and dual-phase contrast-enhanced scans by DLSCT within one week before surgery.Taking pathological results as the golden standard,the accuracy rates of tumor staging were calculated and compared between the multiple-parameter maps derived from DLSCT and 120 kVp polyenergetic image.The effective atomic number(Z-eff)from plain scan,iodine concentration(IC)from arterial phase(AP)and venous phase(VP)were measured.The normalized iodine concentration(NIC)in AP and VP were calculated.The differences of Z-eff,NICAP and NICVP were compared among the pT1-2,pT3 and pT4 groups.The correlation between the pT stages and above values was assessed and the diagnostic efficiencies were analyzed.Results The overall accuracy rate(88.46%vs.67.95%;χ2=9.628,P=0.002),the pT1-2 staging accuracy rate(80.00%vs.40.00%;χ2=6.667,P=0.01),and the pT3 staging accuracy rate(88.10%vs.69.05%;χ2=4.525,P=0.033)of multiple-parameter maps derived from DLSCT were significantly higher than those of 120 kVp polyenergetic image,respectively.The Z-eff,NICAP and NICVP were significantly different among pT stage groups(F=6.456,11.029,12.698,all P<0.05)and exhibited a positive correlation with pT stages(r=0.371,0.367,0.363,all P<0.01).The areas under the curve of Z-eff,NICAP and NICVP to assess pT3-4 staging RA were 0.77,0.71 and 0.74,respectively.Conclusion The multiple-parameter maps derived from DLSCT can significantly improve the diagnostic accuracy of preoperative tumor staging of RA.Z-eff from plain scan and NIC from dual-phase helps differentiate pT1-2 from pT3-4 staging RA.

Progress of Multi-Parameter Magnetic Resonance Imaging in Evaluating the Efficacy of Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer / 中国医学影像学杂志

Neoadjuvant chemoradiotherapy is a part of the current standard treatment mode for locally advanced rectal cancer,which enables a certain proportion of patients to achieve complete tumor response,improving the surgical resection rate and anal retention rate,and then prolonging the disease-free survival period of patients.MRI is the preferred imaging examination to evaluate the efficacy of neoadjuvant therapy.With the development of functional MRI,quantitative parameters derived from different imaging principles can provide more biological information about tumors,improving the clinical application value of MRI.Multi-parameter MRI combining conventional MRI sequences and functional sequences can more comprehensively evaluate the efficacy of neoadjuvant therapy,which is conducive to developing individualized treatment plans for patients in clinical practice and realize precision medicine.

Restaging magnetic resonance imaging of the rectum after neoadjuvant therapy: a practical guide / Ressonância magnética do reto no reestadiamento após terapia neoadjuvante: um guia prático

Abstract Colorectal cancer is the third most common cancer and the second leading cause of cancer-related death. Rectal cancer accounts for approximately one-third of new colorectal cancer cases, with adenocarcinoma as the predominant subtype. Despite an overall decline in colorectal cancer incidence and mortality, due to advancements in screening, early diagnosis, and treatment options, there is a concerning increase in incidence rates among young patients. Recent significant advances in managing locally advanced rectal cancer, such as the establishment of different surgical approaches, neoadjuvant treatment using different protocols for high-risk cases, and the adoption of organ-preservation strategies, have increased the importance of the role played by radiologists in locoregional assessment on magnetic resonance imaging at baseline, at restaging, and during active surveillance of patients with rectal cancer. In this article, we review the role of restaging rectal magnetic resonance imaging after neoadjuvant therapy, providing radiologists with a practical, step-by-step guide for assessing treatment response.

Resumo O câncer colorretal é o terceiro câncer mais comum e a segunda principal causa de morte relacionada ao câncer. O câncer retal representa aproximadamente um terço dos novos casos de câncer colorretal, sendo o adenocarcinoma o subtipo predominante. Apesar de uma diminuição geral na incidência e mortalidade, impulsionada por avanços na prevenção do câncer, diagnóstico precoce e opções de tratamento aprimoradas, há uma preocupante elevação nas taxas entre os pacientes jovens. Avanços recentes significativos no manejo do câncer retal localmente avançado, como abordagens cirúrgicas, o uso de diferentes protocolos de tratamento neoadjuvante para casos de alto risco e a adoção de estratégias de preservação de órgãos, aumentaram o papel dos radiologistas na avaliação locorregional por meio da ressonância magnética na avaliação inicial, reestadiamento e vigilância ativa de pacientes com câncer retal. Este manuscrito tem como objetivo revisar o papel da ressonância magnética retal no reestadiamento após terapia neoadjuvante, fornecendo aos radiologistas um guia prático para revisar exames nesse contexto.

Impact of Treatment Technique on Testicular Dose and Sexual Activity in Rectal Cancer Patients

Objective To estimate the incidental radiation dose delivered to the testicles in three dimensional conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT), and volumetric-modulated arc therapy (VMAT) in rectal cancer patients and its impact on sexual activity using a quality-of-life questionnaire. Materials and Methods The present study included 40 male patients, aged between 25 and 50 years. with locally-advanced rectal cancer, who would undergo neoadjuvant radiotherapy at a dose of 45 Gray (Gy) in 25 fractions (fr) in the supine position. Planning was performed for three techniques: 3DCRT, IMRT, and VMAT. The testicular dose, testicular volume, planning target volume (PTV), the distance of the tumor from the anal verge, and tumor thickness and length in each plan were recorded. A qualityof-life questionnaire pertaining only to sexual activity by the European Organization for Research and Treatment of Cancer­Quality of Life in Colorectal (EORTC QLQ-CR29) and the Functional Assessment of Cancer Therapy­Colorectal (FACT-C) were used to assess the posttreatment effect on sexual life. Results The mean values for tumor length, thickness, and PTV were of 8.9 cm, 1.77 cm and 1,352 cm3 respectively. The mean dose to the right and left testicles (in centigray, cGy) were as follows: 3DCRT ­ 336.23 and 206.65; IMRT ­ 165.15 and 140.25; and VMAT ­ 209.2 and 229.2 respectively. A significant correlation was observed involving the PTV and testicular volume and the incidental testicular dose received. The questionnaire-based analysis of sexual activity included 31 patients who were alive, of whom 27 had resumed their normal sexual life 3 months after the treatment without difficulty (score 4). Conclusion The IMRT showed a significant reduction in the testicular dose when compared to 3DCRT and VMAT. The PTV and testicular volume presented a statistically significant impact on the testicular dose, and the main reason for abstinence was nervousness about disease recurrence.

Primary Anorectal Melanoma: Case Report and Review of a Rare Neoplasm

Primary anorectal melanoma is a rare malignant melanocytic neoplasm; its principal manifestation is rectal bleeding. It has an ominous prognosis with a five-year survival rate of 10%. The case of a 56-year-old woman with rectal bleeding and the sensation of a rectal mass is presented. A polypoid lesion, resected transanally, was documented in the distal rectum during the colonoscopy. The histological study confirmed a primary anorectal melanoma.

El melanoma anorrectal primario es una neoplasia melanocítica maligna poco frecuente, su principal manifestación es el sangrado rectal. Tiene un pronóstico ominoso con una tasa de sobrevida del 10% a 5 años. Se presenta el caso de una mujer de 56 años con rectorragia y sensación de masa rectal. Durante la colonoscopia se documentó una lesión polipoide en el recto distal, que se resecó por vía transanal. El estudio histológico confirmó la presencia de un melanoma anorrectal primario.

Construction and validation of rectal cancer prognostic model by LASSO-Cox regression / 安徽医科大学学报

Objective To construct and appraise a new model for predicting the prognosis of rectal cancer patients using the Lasso-Cox strategy.Methods The clinical pathological data of 599 rectal cancer patients who underwent radical resection were analyzed.Comparison between groups,Lasso and Cox regression were used to select varia-bles and construct a model,and its discrimination,consistency,and clinical benefits were appraised by the receiv-er operating characteristic(ROC),calibration curve,and decision curve analysis.Results Comparison between groups showed that age,body mass index(BMI),preoperational nutrition status,carbohydrate antigen199(CA199),preoperative chemotherapy,intraoperative blood transfusion,vascular or nerve invasion,cancer nod-ules,pathologic T,N,and TNM stages,tumor recurrence or metastasis,radiotherapy and postoperative survival time were associated with grouping of death or survival in rectal cancer patients.Among them,8 variables were se-lected by lasso and contained into the Cox regression model.Age(HR=1.04,P＜0.05),BMI(HR=0.89,P＜0.05),blood transfusion(HR=2.29,P＜0.05),postoperative chemotherapy(HR=0.16,P＜0.01),recur-rence(HR=43.67,P＜0.01),and metastasis(HR=2.75,P＜0.05)were identified as independent prognostic factors,which were used to construct a nomogram model.The area under the curve(AUC)and the 95％confi-dence interval of the receiver operating characteristic(ROC)curve of the predictive model was 0.95(0.91-0.99),P＜0.01.The predicted probability of 1-year and 3-year survival was close to the actual probability.The DCA curve of the model was far away from a decision line parallel to the X-axis and another line with a negative slope.Conclusion The newly established nomogram has good discrimination,consistency and clinical benefits,which help predict the prognosis of rectal cancer after surgery.

Recent progress in early closure of protective ileostomy after rectal cancer surgery / 国际外科学杂志

The timing for closure of prophylactic ileostomy after rectal cancer surgery is not unified, and it is generally recommended to return the stoma after 3 months. With the application of enhanced recovery after surgery in clinical patients and the continuous progress of technology, the effectiveness and safety of early ileostomy closure (EIC) are the focus of current researches. More and more patients with rectal cancer begin to receive neoadjuvant chemoradiotherapy, which also brings uncertainty to the time of ileostomy closure. prophylactic ileostomy not only brings about stoma-related complications, but also brings great psychological burden to patients. Some patients have an urgent need for EIC, but there is no consensus on the optimal timing for EIC and which patients need EIC. This article reviews the advantages, controversies, optimal timing, the influence of chemoradiotherapy, the indications and contraindications of early closure and provide reference for clinicians.

Value of MRI histogram in predicting survival of patients undergoing surgical treatment of colorectal cancer / 中华消化外科杂志

Objective:To investigate the value of multi-stage dynamic contrast enhanced MRI (DCE-MRI) histogram in predicting survival of patients undergoing surgical treatment of colorectal cancer (CRC).Methods:The retrospective cohort study was conducted. The clinico-pathological data of 81 patients with CRC who were admitted to the Jiuquan City People′s Hospital from January 2018 to February 2019 were collected. There were 47 males and 34 females, aged (62±6)years. All patients underwent routine MRI and DCE-MRI examination to extract relevant imaging parameters. Observation indicators: (1) treatment, imaging examination and follow-up; (2) imaging factors influencing postoperative disease-free survival of patients with CRC. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers. Univariate and multivariate analyses were conducted using the COX proportional risk model. Pearson correlation test was used to analyze and exclude factors with correlation in univariate analysis, and the multi-variate analysis was conducted on the rest of factors. The Kaplan-Meier method was used to calculate survival rates, and Log-Rank test was used for survival analysis. Results:(1) Treatment, imaging examination and follow-up. All 81 patients underwent preoperative MRI plain scan, enhanced imaging, and diffusion weighted imaging. After complete examination, all patients underwent radical resection of CRC and received postoperative chemotherapy using the FOLFOX regimen. All 81 patients were followed up for 42(range, 11-61)months after surgery. The 1-, 3-, 5-year overall survival rate of 81 patients after surgery was 98.8%, 96.3%, 93.8%, respectively. During the follow-up period, 56 of the 81 patients survived from disease-free and 25 patients had disease progressed. (2) Imaging factors influencing postoperative disease-free survival of patients with CRC. Results of multivariate analysis showed that the kurtosis value and skewness value of positive enhancement integral (PEI) were independent imaging factors influencing postoperative disease-free survival of patients of CRC ( odds ratio=1.840, 1.243, 95% confidence interval as 1.403-2.412, 1.020-1.516, P<0.05). Taking the median values of kurtosis value and skewness value of PEI as 4.864 and 5.042 for further analysis. The postoperative 5-year disease-free survival rate of patients with kurtosis value of PEI <4.864 and ≥4.864 was 89.7% and 10.3%, showing a significant difference between them ( χ2=31.265, P<0.05). The postoperative 5-year disease-free survival rate of patients with skewness value of PEI<5.042 and ≥5.042 was 63.4% and 36.6%, showing a significant difference between them ( χ2=8.164, P<0.05). Conclusions:The kurtosis value and skewness value of PEI in DCE-MRI are independent imaging factors influencing postoperative disease-free survival of patients of CRC. The DCE-MRI histogram can effectively evaluate the postoperative prognosis of patients of CRC.

Clinical value of magnetic resonance imaging based integrated deep learning model for predic-ting the times of linear staplers used in middle-low rectal cancer resection / 中华消化外科杂志

Objective:To investigate the clinical value of magnetic resonance imaging (MRI) based integrated deep learning model for predicting the times of linear staplers used in double stapling technique for middle-low rectal cancer resection.Methods:The retrospective cohort study was conducted. The clinicopathological data of 263 patients who underwent low anterior resection (LAR) for middle-low rectal cancer in Ruijin Hospital of Shanghai Jiaotong University School of Medicine from January 2018 to December 2022 were collected as training dataset. There were 183 males and 80 females, aged 63(55,68)years. The clinicopathological data of 128 patients with middle-low rectal cancer were collected as validation dataset, including 83 males and 45 females, with age as 65(57,70)years. The training dataset was used to construct the prediction model, and the validation dataset was used to validate the prediction model. Observation indicators: (1) clinicopathological features of patients in the training dataset; (2) influencing factors for ≥3 times using of linear staplers in the operation; (3) prediction model construction; (4) efficiency evaluation of prediction model; (5) validation of prediction model. Measurement data with skewed distribution were represented as M( Q1, Q3), and Mann-Whitney U test was used for comparison between groups. Count data were expressed as absolute numbers, and comparison between groups was conducted using the chi-square test. Wilcoxon rank sum test was used for non-parametric data analysis. Univariate analysis was conducted using the Logistic regression model, and multivariate analysis was conducted using the Logistic stepwise regression model. The receiver operating characteristic (ROC) curve was draw and the area under the curve (AUC) was calculated. The AUC of the ROC curve >0.75 indicated the prediction model as acceptable. Comparison of AUC was conducted using the Delong test. Results:(1) Clinicopathological features of patients in the training dataset. Of the 263 patients, there were 48 cases with linear staplers used in the operation ≥3 times and 215 cases with linear staplers used in the operation ≤2 times. Cases with preoperative serum carcinoembryonic antigen (CEA) >5 μg/L, cases with anastomotic leakage, cases with tumor diameter ≥5 cm were 20, 12, 13 in the 48 cases with linear staplers used ≥3 times in the operation, versus 56, 26, 21 in the 215 cases with linear staplers used ≤2 times in the operation, showing significant differences in the above indicators between them ( χ2=4.66, 5.29, 10.45, P<0.05). (2) Influencing factors for ≥3 times using of linear staplers in the operation. Results of multivariate analysis showed that preoperative serum CEA >5 μg/L and tumor diameter ≥5 cm were independent risk factors for ≥3 times using of linear staplers in the operation ( odds ratio=2.26, 3.39, 95% confidence interval as 1.15-4.43, 1.50-7.65, P<0.05). (3) Prediction model construction. According to the results of multivariate analysis, the clinical prediction model was established as Logit(P)=-2.018+0.814×preoperative serum CEA (>5 μg/L as 1, ≤5 μg/L as 0)+ 1.222×tumor diameter (≥5 cm as 1, <5 cm as 0). The image data segmented by the Mask region convolutional neural network (MASK R-CNN) was input into the three-dimensional convolutional neural network (C3D), and the image prediction model was constructed by training. The image data segmented by the MASK R-CNN and the clinical independent risk factors were input into the C3D, and the integrated prediction model was constructed by training. (4) Efficiency evaluation of prediction model. The sensitivity, specificity and accuracy of the clinical prediction model was 70.0%, 81.0% and 79.4%, respectively, with the Yoden index as 0.51. The sensitivity, specificity and accuracy of the image prediction model was 50.0%, 98.3% and 91.2%, respectively, with the Yoden index as 0.48. The sensitivity, specificity and accuracy of the integrated prediction model was 70.0%, 98.3% and 94.1%, respectively, with the Yoden index as 0.68. The AUC of clinical prediction model, image prediction model and integrated prediction model was 0.72(95% confidence interval as 0.61-0.83), 0.81(95% confidence interval as 0.71-0.91) and 0.88(95% confidence interval as 0.81-0.95), respectively. There were significant differences in the efficacy between the integrated prediction model and the image prediction model or the clinical prediction model ( Z=2.98, 2.48, P<0.05). (5) Validation of prediction model. The three prediction models were externally validated by validation dataset. The sensitivity, specificity and accuracy of the clinical prediction model was 62.5%, 66.1% and 65.6%, respectively, with the Yoden index as 0.29. The sensitivity, specificity and accuracy of the image prediction model was 58.8%, 95.5% and 92.1%, respectively, with the Yoden index as 0.64. The sensitivity, specificity and accuracy of the integrated prediction model was 68.8%, 97.3% and 93.8%, respectively, with the Yoden index as 0.66. The AUC of clinical prediction model, image prediction model and integrated prediction model was 0.65(95% confidence interval as 0.55-0.75), 0.75(95% confidence interval as 0.66-0.84) and 0.84(95% confidence interval as 0.74-0.93), respec-tively. There was significant differences in the efficacy between the clinical prediction model and the integrated prediction model ( Z=3.24, P<0.05). Conclusion:The MRI-based deep-learning model can help predicting the high-risk population with ≥3 times using of linear staplers in resection of middle-low rectal cancer with double stapling technique.

Molecular typing and precise treatment strategies for colorectal cancer: from experience to precision / 中华消化外科杂志

Represented by colorectal cancer, gastrointestinal malignancies have unique clinical characteristics and biological behaviors, ranking high in the incidence and mortality rates in China. In recent years, with technological innovations and continuous optimization of disease management models, the concept of "precision surgery" has been driving the transformation of colorectal cancer surgery from traditional empirical surgical paradigms to modern precision surgical paradigms. Rapid advancements have been made in colorectal surgical treatment, including surgical techniques, instrument platforms, various novel targeted therapies, and immune combination therapies, which have demonstrated significant efficacy in colorectal cancer treatment. Meanwhile, with 30 years of development in laparoscopic colorectal surgery in China, the surgical approach for colorectal cancer has shifted from traditional open-bellied surgery to minimally invasive surgery. The diagnostic and therapeutic models for colorectal cancer patients have gradually transitioned from experience-driven to precision-based and individualized care. Guided by the concept of "precision surgery", this article combines the current status and trends in colorectal cancer surgery to discuss relevant molecular subtyping and precision treatment strategies, aiming to promote precise surgery and comprehensive treatment for colorectal cancer.