Surgeon assessment of significant rectal polyps using white light endoscopy alone and in comparison to fluorescence-augmented AI lesion classification.

PURPOSE: Perioperative decision making for large (> 2 cm) rectal polyps with ambiguous features is complex. The most common intraprocedural assessment is clinician judgement alone while radiological and endoscopic biopsy can provide periprocedural detail. Fluorescence-augmented machine learning (FA-ML) methods may optimise local treatment strategy. METHODS: Surgeons of varying grades, all performing colonoscopies independently, were asked to visually judge endoscopic videos of large benign and early-stage malignant (potentially suitable for local excision) rectal lesions on an interactive video platform (Mindstamp) with results compared with and between final pathology, radiology and a novel FA-ML classifier. Statistical analyses of data used Fleiss Multi-rater Kappa scoring, Spearman Coefficient and Frequency tables. RESULTS: Thirty-two surgeons judged 14 ambiguous polyp videos (7 benign, 7 malignant). In all cancers, initial endoscopic biopsy had yielded false-negative results. Five of each lesion type had had a pre-excision MRI with a 60% false-positive malignancy prediction in benign lesions and a 60% over-staging and 40% equivocal rate in cancers. Average clinical visual cancer judgement accuracy was 49% (with only 'fair' inter-rater agreement), many reporting uncertainty and higher reported decision confidence did not correspond to higher accuracy. This compared to 86% ML accuracy. Size was misjudged visually by a mean of 20% with polyp size underestimated in 4/6 and overestimated in 2/6. Subjective narratives regarding decision-making requested for 7/14 lesions revealed wide rationale variation between participants. CONCLUSION: Current available clinical means of ambiguous rectal lesion assessment is suboptimal with wide inter-observer variation. Fluorescence based AI augmentation may advance this field via objective, explainable ML methods.

Treatment of Locally Advanced Rectal Cancer in the Era of Total Neoadjuvant Therapy: A Systematic Review and Network Meta-Analysis.

Importance: Treatment of locally advanced rectal cancer (LARC) involves neoadjuvant chemoradiotherapy plus total mesorectal excision and adjuvant chemotherapy. However, total neoadjuvant therapy (TNT) protocols (ie, preoperative chemotherapy in addition to radiotherapy) may allow better adherence and early treatment of distant micrometastases and may increase pathological complete response (pCR) rates. Objective: To assess the efficacy and tolerability of TNT protocols for LARC. Data Sources: MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science Core Collection electronic databases and ClinicalTrials.gov for unpublished studies were searched from inception to March 2, 2024. Study Selection: Randomized clinical trials including adults with LARC who underwent rectal resection as a final treatment were included. Studies including nonoperative treatment (watch-and-wait strategy), treatments other than rectal resection, immunotherapy, or antiangiogenic agents were excluded. Among the initially identified studies, 2.9% met the selection criteria. Data Extraction and Synthesis: Two authors independently screened the records and extracted data. Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA)-compliant pairwise and network meta-analyses with a random-effects model were performed in a frequentist framework, and the certainty of evidence was assessed according to the confidence in network meta-analysis approach. Main Outcomes and Measures: The primary outcome was pCR, defined as the absence of residual tumor at pathological assessment after surgery. Secondary outcomes included tolerability, toxic effects, perioperative outcomes, and long-term survival. Results: Of 925 records identified, 27 randomized clinical trials, including 13 413 adults aged 18 years or older (median age, 60.0 years [range, 42.0-63.5 years]; 67.2% male) contributed to the primary network meta-analysis. With regard to pCR, long-course chemoradiotherapy (L-CRT) plus consolidation chemotherapy (relative risk [RR], 1.96; 95% CI, 1.25-3.06), short-course radiotherapy (S-RT) plus consolidation chemotherapy (RR, 1.76; 95% CI, 1.34-2.30), and induction chemotherapy plus L-CRT (RR, 1.57; 95% CI, 1.09-2.25) outperformed standard L-CRT with single-agent fluoropyrimidine-based chemotherapy. Considering 3-year disease-free survival, S-RT plus consolidation chemotherapy (RR, 1.08; 95% CI, 1.01-1.14) and induction chemotherapy plus L-CRT (RR, 1.12; 95% CI, 1.01-1.24) outperformed L-CRT, in spite of an increased 5-year locoregional recurrence rate of S-RT plus consolidation chemotherapy (RR, 1.65; 95% CI, 1.03-2.63). Conclusions and Relevance: In this systematic review and network meta-analysis, 3 TNT protocols were identified to outperform the current standard of care in terms of pCR rates, with good tolerability and optimal postoperative outcomes, suggesting they should be recognized as first-line treatments.

Preoperative prediction of perineural invasion of rectal cancer based on a magnetic resonance imaging radiomics model: A dual-center study.

BACKGROUND: Perineural invasion (PNI) has been used as an important pathological indicator and independent prognostic factor for patients with rectal cancer (RC). Preoperative prediction of PNI status is helpful for individualized treatment of RC. Recently, several radiomics studies have been used to predict the PNI status in RC, demonstrating a good predictive effect, but the results lacked generalizability. The preoperative prediction of PNI status is still challenging and needs further study. AIM: To establish and validate an optimal radiomics model for predicting PNI status preoperatively in RC patients. METHODS: This retrospective study enrolled 244 postoperative patients with pathologically confirmed RC from two independent centers. The patients underwent pre-operative high-resolution magnetic resonance imaging (MRI) between May 2019 and August 2022. Quantitative radiomics features were extracted and selected from oblique axial T2-weighted imaging (T2WI) and contrast-enhanced T1WI (T1CE) sequences. The radiomics signatures were constructed using logistic regression analysis and the predictive potential of various sequences was compared (T2WI, T1CE and T2WI + T1CE fusion sequences). A clinical-radiomics (CR) model was established by combining the radiomics features and clinical risk factors. The internal and external validation groups were used to validate the proposed models. The area under the receiver operating characteristic curve (AUC), DeLong test, net reclassification improvement (NRI), integrated discrimination improvement (IDI), calibration curve, and decision curve analysis (DCA) were used to evaluate the model performance. RESULTS: Among the radiomics models, the T2WI + T1CE fusion sequences model showed the best predictive performance, in the training and internal validation groups, the AUCs of the fusion sequence model were 0.839 [95% confidence interval (CI): 0.757-0.921] and 0.787 (95%CI: 0.650-0.923), which were higher than those of the T2WI and T1CE sequence models. The CR model constructed by combining clinical risk factors had the best predictive performance. In the training and internal and external validation groups, the AUCs of the CR model were 0.889 (95%CI: 0.824-0.954), 0.889 (95%CI: 0.803-0.976) and 0.894 (95%CI: 0.814-0.974). Delong test, NRI, and IDI showed that the CR model had significant differences from other models (P < 0.05). Calibration curves demonstrated good agreement, and DCA revealed significant benefits of the CR model. CONCLUSION: The CR model based on preoperative MRI radiomics features and clinical risk factors can preoperatively predict the PNI status of RC noninvasively, which facilitates individualized treatment of RC patients.

Evaluating complete response prediction rates in locally advanced rectal cancer with different radiomics segmentation approaches.

Purpose: Studies examining prediction of complete response (CR) in locally advanced rectum cancer (LARC) from pre/post chemoradiotherapy (CRT) magnetic resonance imaging (MRI) are performed mostly with segmentations of the tumor, whereas only in two studies segmentation included tumor and mesorectum. Additionally, pelvic extramesorectal region, which is included in the clinical target volume (CTV) of radiotherapy, may contain information. Therefore, we aimed to compare predictive rates of radiomics analysis with features extracted from segmentations of tumor, tumor+mesorectum, and CTV. Methods and materials: Ninety-three LARC patients who underwent CRT in our institution between 2012 and 2019 were retrospectively scanned. Patients were divided into CR and non-CR groups. Tumor, tumor+mesorectum and CTV were segmented on T2 preCRT MRI images. Extracted features were compared for best area under the curve (AUC) of CR prediction with 15 machine-learning models. Results: CR was observed in 25 patients (26.8%), of whom 13 had pathological, and 12 had clinical complete response. For tumor, tumor+mesorectum and CTV segmentations, the best AUC were 0.84, 0.81, 0.77 in the training set and 0.85, 0.83 and 0.72 in the test set, respectively; sensitivity and specificity for the test set were 76%, 90%, 76% and 71%, 67% and 62%, respectively. Conclusion: Although the highest AUC result is obtained from the tumor segmentation, the highest accuracy and sensitivity are detected with tumor+mesorectum segmentation and these findings align with previous studies, suggesting that the mesorectum contains valuable insights for CR. The lowest result is obtained with CTV segmentation. More studies with mesorectum and pelvic nodal regions included in segmentation are needed.

The impact of robotic rectal cancer surgery at a Canadian regional cancer centre: a retrospective cohort study.

BACKGROUND: Although robotic surgery has several advantages over other minimally invasive surgery (MIS) techniques for rectal cancer surgery, the uptake in Canada has been limited owing to a perceived increase in cost and lack of training. The objective of this study was to determine the impact of access to robotic surgery in a Canadian setting. METHODS: We conducted a retrospective cohort study involving consecutive adults undergoing surgical resection for rectal cancer between 2017 and 2020. The primary exposure was access to robotic surgery. Outcomes included MIS utilization, short-term outcomes, total cost of care, and quality of surgical resection. We completed univariate and multivariate analyses. RESULTS: We included 171 individuals in this cohort study (85 in the prerobotic period and 86 in the robotic period). The 2 groups had similar baseline characteristics. A higher proportion of individuals underwent successful MIS in the robotic phase (86% v. 46%, p < 0.001). Other benefits included a shorter mean length of hospital stay (5.1 d v. 9.2 d, p < 0.001). The quality of surgical resection was similar between groups. The total cost of care was $16 746 in the robotic period and $18 808 in the prerobotic period (mean difference -$1262, 95% confidence interval -$4308 to $1783; p = 0.4). CONCLUSION: Access to robotic rectal cancer surgery increased successful completion of MIS and shortened hospital stay, with a similar total cost of care. Robotic rectal cancer surgery can enhance patient outcomes in the Canadian setting.

Impact of tumor size on overall survival and cancer-specific survival of early-onset colon and rectal cancer: a retrospective cohort study.

PURPOSE: This study aimed to investigate the impact of tumor size on survival in early-onset colon and rectal cancer. METHODS: Early-onset colon and rectal cancer patients were identified from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. Tumor size was analyzed as both continuous and categorical variables. Several statistical techniques, including restricted cubic spline (RCS), Cox proportional hazard model, subgroup analysis, propensity score matching (PSM), and Kaplan-Meier survival analysis, were employed to demonstrate the association between tumor size and overall survival (OS) and cancer-specific survival (CSS) of early-onset colon and rectal cancer. RESULTS: Seventeen thousand five hundred fifty-one (76.7%) early-onset colon and 5323 (23.3%) rectal cancer patients were included. RCS analysis confirmed a linear association between tumor size and survival. Patients with a tumor size > 5 cm had worse OS and CSS, compared to those with a tumor size ≤ 5 cm for both early-onset colon and rectal cancer. Notably, subgroup analysis showed that a smaller tumor size (≤ 50 mm) was associated with worse survival in stage II early-onset colon cancer, although not statistically significant. After PSM, Kaplan-Meier survival curves showed that the survival of patients with tumor size ≤ 50 mm was better than that of patients with tumor size > 50 mm. CONCLUSION: Patients with tumors larger than 5 cm were associated with worse survival in early-onset colon and rectal cancer. However, smaller tumor size may indicate a more biologically aggressive phenotype, correlating with poorer survival in stage II early-onset colon cancer.

Short-term and long-term outcomes after robotic radical surgery for rectal gastrointestinal stromal tumor.

BACKGROUND: The optimal approach for ensuring both complete resection and preservation of anal function in rectal gastrointestinal stromal tumor (GIST) remains unknown. The aim of this study was to clarify short-term and long-term outcomes after robotic radical surgery for rectal GIST. METHODS: A total of 13 patients who underwent robotic radical surgery for rectal GIST between December 2011 and April 2022 were included. All robotic procedures were performed using a systematic approach. A supplemental video of robotic radical surgery for rectal GIST is attached. The short-term outcome was the incidence of postoperative complications during the first 30 days after surgery. Surgical outcomes were retrieved from a prospective database. Long-term outcomes, including overall survival and recurrence-free survival, were determined in all patients. RESULTS: Median distance from the tumor to the anal verge was 4.0 cm. Surgical margins were negative in all patients. Two patients underwent neoadjuvant imatinib therapy. All patients underwent sphincter-preserving surgery. None underwent conversion to open or laparoscopic surgery. The incidence of postoperative Clavien-Dindo grade II and grade ≥ III complications was 7.7% and 0%, respectively. The median postoperative hospital stay was 7 days. Twelve patients (92.3%) underwent stoma closure within 5 months of the initial surgery. Median follow-up time was 76 months. The 5-year overall survival and recurrence-free survival rates were both 100%. None of the patients had recurrence. CONCLUSION: Short-term and long-term outcomes after radical robotic surgery for rectal GIST were favorable. Robotic surgery might be a useful surgical approach for rectal GIST.

Meta-analysis: loop ileostomy versus colostomy to prevent complications of anterior resection for rectal cancer.

PURPOSE: Anastomotic leakage is a serious complication of colorectal cancer surgery, prolonging hospital stays and impacting patient prognosis. Preventive colostomy is required in patients at risk of anastomotic fistulas. However, it remains unclear whether the commonly used loop colostomy(LC) or loop ileostomy(LI) can reduce the complications of colorectal surgery. This study aims to compare perioperative morbidities associated with LC and LI following anterior rectal cancer resection, including LC and LI reversal. METHODS: In this meta-analysis, the Embase, Web of Science, Scopus, PubMed, and Cochrane Library databases were searched for prospective cohort studies, retrospective cohort studies, and randomized controlled trials (RCTs) on perioperative morbidity during stoma development and reversal up to July 2023, The meta-analysis included 10 trials with 2036 individuals (2 RCTs and 8 cohorts). RESULTS: No significant differences in morbidity, mortality, or stoma-related issues were found between the LI and LC groups after anterior resection surgery. However, patients in the LC group exhibited higher rates of stoma prolapse (RR: 0.39; 95%CI: 0.19-0.82; P = 0.01), retraction (RR: 0.45; 95%CI: 0.29-0.71; P < 0.01), surgical site infection (RR: 0.52; 95%CI: 0.27-1.00; P = 0.05) and incisional hernias (RR: 0.53; 95%CI: 0.32-0.89; P = 0.02) after stoma closure compared to those in the LI group. Conversely, the LI group showed higher rates of dehydration or electrolyte imbalances(RR: 2.98; 95%CI: 1.51-5.89; P < 0.01), high-output(RR: 6.17; 95%CI: 1.24-30.64; P = 0.03), and renal insufficiency post-surgery(RR: 2.51; 95%CI: 1.01-6.27; P = 0.05). CONCLUSION: Our study strongly recommends a preventive LI for anterior resection due to rectal cancer. However, ileostomy is more likely to result in dehydration, renal insufficiency, and intestinal obstruction. More multicenter RCTs are needed to corroborate this.

Spatial transcriptomic analysis reveals local effects of intratumoral fusobacterial infection on DNA damage and immune signaling in rectal cancer.

Mucinous colorectal cancer (CRC) is a common histological subtype of colorectal adenocarcinoma, associated with a poor response to chemoradiotherapy. The commensal facultative anaerobes fusobacteria, have been associated with poor prognosis specifically in mesenchymal CRC. Interestingly, fusobacterial infection is especially prevalent in mucinous CRC. The objective of this study was therefore to increase our understanding of beneficial and detrimental effects of fusobacterial infection, by contrasting host cell signaling and immune responses in areas of high vs. low infection, using mucinous rectal cancer as a clinically relevant example. We employed spatial transcriptomic profiling of 106 regions of interest from 8 mucinous rectal cancer samples to study gene expression in the epithelial and immune segments across regions of high versus low fusobacterial infection. Fusobacteria high regions were associated with increased oxidative stress, DNA damage, and P53 signaling. Meanwhile regions of low fusobacterial prevalence were characterized by elevated JAK-STAT, Il-17, Il-1, chemokine and TNF signaling. Immune masks within fusobacterial high regions were characterized by elevated proportions of cytotoxic (CD8+) T cells (p = 0.037), natural killer (NK) cells (p < 0.001), B-cells (p < 0.001), and gamma delta T cells (p = 0.003). Meanwhile, fusobacteria low regions were associated with significantly greater M2 macrophage (p < 0.001), fibroblast (p < 0.001), pericyte (p = 0.002), and endothelial (p < 0.001) counts.

Advancing mid-rectal cancer surgery: Unveiling the potential of natural orifice specimen extraction surgery in comparison to conventional laparoscopic-assisted resection.

BACKGROUND: Mid-rectal cancer treatment traditionally involves conventional laparoscopic-assisted resection (CLAR). This study aimed to assess the clinical and therapeutic advantages of Natural Orifice Specimen Extraction Surgery (NOSES) over CLAR. AIMS: To compare the clinical outcomes, intraoperative metrics, postoperative recovery, complications, and long-term prognosis between NOSES and CLAR groups. MATERIALS & METHODS: A total of 136 patients were analyzed, with 92 undergoing CLAR and 44 undergoing NOSES. Clinical outcomes were evaluated, and propensity score matching (PSM) was employed to control potential biases. RESULTS: The NOSES group exhibited significant improvements in postoperative recovery, including lower pain scores on days 1, 3, and 5 (p < .001), reduced need for additional analgesics (p = .02), shorter hospital stays (10.8 ± 2.3 vs. 14.2 ± 5.3 days; p < .001), and decreased intraoperative blood loss (48.1 ± 52.7 mL vs. 71.0 ± 55.0 mL; p = .03). Patients undergoing NOSES also reported enhanced satisfaction with postoperative abdominal appearance and better quality of life. Additionally, the NOSES approach resulted in fewer postoperative complications. CONCLUSION: While long-term outcomes (overall survival, disease-free survival, and local recurrence rates) were comparable between the two methods, NOSES demonstrated superior postoperative outcomes compared to CLAR in mid-rectal cancer treatment, while maintaining similar long-term oncological safety. These findings suggest that NOSES could serve as an effective alternative to CLAR without compromising long-term results.

[Treatment of localized rectal cancer in 2024]. / Prise en charge du cancer du rectum localisé en 2024.

The management of localized rectal cancer has evolved significantly over the last two years. On one hand, intensification of treatments (radio-chemotherapy, chemotherapy, then surgery) for the most advanced tumors has shown an improvement in clinical results compared to less intense regiments. On the other hand, the possibility, as for prostate cancers, of opting for active surveillance without surgery in patients presenting a complete clinical response after a treatment phase, is now accepted. More recently, the Swiss recommendations for the surveillance of rectal cancer have been modified and now differ from those of colon cancers, by incorporating pelvic MRI and rectoscopy in addition, as well as special guidelines for tumors under active surveillance.

La prise en charge du cancer du rectum localisé a beaucoup évolué ces deux dernières années. D'un côté, l'intensification des traitements (radio-chimiothérapie, chimiothérapie, puis chirurgie) pour les tumeurs les plus avancées a montré une amélioration des résultats cliniques par rapport aux traitements moins intenses. De l'autre côté, la possibilité, comme pour les cancers de la prostate, d'opter pour une surveillance active sans chirurgie chez les patients présentant une réponse clinique complète après une phase de traitement est aujourd'hui acceptée. Plus récemment, les recommandations suisses pour la surveillance du cancer du rectum ont été modifiées et se différencient maintenant de celles des cancers du côlon, en incorporant IRM pelvienne et rectoscopie en sus, de même qu'un suivi spécial pour les tumeurs en surveillance active.

Case report: Decreased hemoglobin and multiple organ failure caused by ceftizoxime-induced immune hemolytic anemia in a Chinese patient with malignant rectal cancer.

Background: Drug-induced immune hemolytic anemia (DIIHA) is a rare but serious condition, with an estimated incidence of one in 100,000 cases, associated with various antibiotics. This study reports on a case of ceftizoxime-induced hemolysis observed in a patient in China. Case description: A Chinese patient diagnosed with malignant rectal cancer underwent antimicrobial therapy after laparoscopic partial recto-sigmoid resection (L-Dixon). After receiving four doses of ceftizoxime, the patient developed symptoms including rash, itchy skin, and chest distress, followed by a rapid decline in hemoglobin levels, the presence of hemoglobin in the urine (hemoglobinuria), renal failure, and disseminated intravascular coagulation. Laboratory analysis revealed high-titer antibodies against ceftizoxime and red blood cells (RBCs) in the patient's serum, including immunoglobulin M (IgM) (1:128) antibodies and immunoglobulin G (IgG) (1:8) antibodies, with noted crossreactivity to ceftriaxone. Significant improvement in the patient's hemolytic symptoms was observed following immediate discontinuation of the drug, two plasma exchanges, and extensive RBC transfusion. Conclusion: This case, together with previous reports, underscores the importance of considering DIIHA in patients who exhibit unexplained decreases in hemoglobin levels following antibiotic therapy. A thorough examination of the patient's medical history can provide crucial insights for diagnosing DIIHA. The effective management of DIIHA includes immediate cessation of the implicated drug, plasma exchange, and transfusion support based on the identification of specific drug-dependent antibodies through serological testing.

Automated, High-Throughput Platform to Generate a High-Reliability, Comprehensive Rectal Cancer Database.

PURPOSE: Dynamic operations platforms allow for cross-platform data extraction, integration, and analysis, although application of these platforms to large-scale oncology enterprises has not been described. This study presents a pipeline for automated, high-fidelity extraction, integration, and validation of cross-platform oncology data in patients undergoing treatment for rectal cancer at a single, high-volume institution. METHODS: A dynamic operations platform was used to identify patients with rectal cancer treated at MD Anderson Cancer Center between 2016 and 2022 who had magnetic resonance imaging (MRI) imaging and preoperative treatment details available in the electronic health record (EHR). Demographic, clinicopathologic, tumor mutation, radiographic, and treatment data were extracted from the EHR using a methodology adaptable to any disease site. Data accuracy was assessed by manual review. Accuracy before and after implementation of synoptic reporting was determined for MRI data. RESULTS: A total of 516 patients with localized rectal cancer were included. In the era after institutional adoption of synoptic reports, the dynamic operations platform extracted T (tumor) category data from the EHR with 95% accuracy compared with 87% before the use of synoptic reports, and N (lymph node) category with 88% compared with 58%. Correct extraction of pelvic sidewall adenopathy was 94% compared with 78%, and extramural vascular invasion accuracy was 99% compared with 89%. Neoadjuvant chemotherapy and radiation data were 99% accurate for patients who had synoptic data sources. CONCLUSION: Using dynamic operations platforms enables automated cross-platform integration of multiparameter oncology data with high fidelity in patients undergoing multimodality treatment for rectal cancer. These pipelines can be adapted to other solid tumors and, together with standardized reporting, can increase efficiency in clinical research and the translation of actionable findings toward optimizing patient outcomes.

[Treatment strategies for recurrent rectal cancer]. / Therapiestrategien beim Rektumkarzinomrezidiv.

Multimodal treatment approaches with neoadjuvant radiotherapy and chemotherapy followed by oncological and total mesorectal excision (TME) have significantly reduced the recurrence rate even in locally advanced rectal cancer. Nevertheless, up to 10% of patients develop a local relapse. Surgical R0 resection is the only chance of a cure in the treatment of locally recurrent rectal cancer (LRRC). Due to the altered anatomy and physiology of the true pelvis as a result of the pretreatment and operations as well as the localization and extent of the recurrence, the treatment decision is individualized and remains a challenge for the interdisciplinary team. Even locally advanced tumors with involvement of adjacent structures can be treated in designated centers using multimodal treatment concepts with potentially curative intent.

Analysis of risk characteristics for early progression and late progression in locally advanced rectal cancer patients: a large population-based and validated study.

BACKGROUND AND OBJECTIVE: The current study aimed to explore the factors influencing early progression (EP) and late progression (LP) in locally advanced rectal cancer (LARC) patients. METHODS: The patients were classified into EP and LP groups using one year as a cutoff. The random survival forest model was utilized to calculate the probability of time-to-progression. Besides, inverse probability of treatment weighting (IPTW) analysis and the Surveillance, Epidemiology, and End Results (SEER) were conducted to validate our results. RESULTS: Our study revealed that PNI, CEA level, and pathological stage were independent prognostic factors for PFS both in EP group and LP group. For EP group patients, Group 1 had the highest probability of progression at the 9th month of follow-up, while Group 2 exhibited the highest probability at the 6th month. Group 3, on the other hand, showed two peaks of progression at the 4th and 8th months of follow-up. As for LP group patients, Groups 4, 5, and 6 all exhibited peaks of progression between the 18th and 24th months of follow-up. Furthermore, our results suggested that PNI was also an independent prognostic factor affecting OS in both EP group and LP group. Finally, the analysis of IPTW and SEER database further confirmed our findings. CONCLUSIONS: Our results indicated a significant correlation between immune and nutritional status with PFS and OS in both EP and LP groups. These insights can aid healthcare professionals in effectively identifying and evaluating patients' nutritional status, enabling them to develop tailored nutrition plans and interventions.

Which Treatment for Which Patient: Rectal Cancer Management After PROSPECT Trial.

Determining treatment options for patients with locally advanced rectal cancer after the PROSPECT trial data readout adds an important level to the decision-making process.

Combined DNA Analysis from Stool and Blood Samples Improves Tumor Tracking and Assessment of Clonal Heterogeneity in Localized Rectal Cancer Patients.

Objectives: In this study, stool samples were evaluated for tumor mutation analysis via a targeted next generation sequencing (NGS) approach in a small patient cohort suffering from localized rectal cancer. Introduction: Colorectal cancer (CRC) causes the second highest cancer-related death rate worldwide. Thus, improvements in disease assessment and monitoring that may facilitate treatment allocation and allow organ-sparing "watch-and-wait" treatment strategies are highly relevant for a significant number of CRC patients. Methods: Stool-based results were compared with mutation profiles derived from liquid biopsies and the gold standard procedure of tumor biopsy from the same patients. A workflow was established that enables the detection of de-novo tumor mutations in stool samples of CRC patients via ultra-sensitive cell-free tumor DNA target enrichment. Results: Notably, only a 19% overall concordance was found in mutational profiles across the compared sample specimens of stool, tumor, and liquid biopsies. Conclusion: Based on these results, the analysis of stool and liquid biopsy samples can provide important additional information on tumor heterogeneity and potentially on the assessment of minimal residual disease and clonal tumor evolution.

Comparison of early and late removal of the urinary catheter after rectal cancer surgery.

OBJECTIVE: This study is aiming to compare the results of early and late removal of urinary catheters after rectal cancer surgery. MATERIALS AND METHODS: Patients who undergone rectal cancer surgery in a single center were included in this prospective randomized study. The timing of the urinary catheter removal was randomized by a computer-assisted program and divided into 2 groups, which are early (first 48 h) and late (after 48 h). The primary outcome of this study was to compare the urinary retention and re-catheterization rates between patients with early and those with late catheter removal. RESULTS: Sixty-six patients were included in this study. The median age was 60 (31-88 years), and the patient group was predominantly male (n: 40, 60.9%). Urinary retention after catheter removal developed in 8 (12%) of 66 patients. There was no difference between the two groups in terms of the need for re-catheterization (14% vs. 10%, p: 0.63). All the patients who required re-catheterization (n: 8) and were discharged with a urinary catheter (n: 4) were male. When the male and female patients were evaluated separately, there was no difference in urinary retention in the early or late groups. CONCLUSIONS: Early or late removal of the catheter does not play a role in the development of urinary retention in patients undergoing rectal cancer surgery.

OBJETIVO: Comparar los resultados de la retirada precoz y tardía de la sonda urinaria tras la cirugía de cáncer rectal. MÉTODO: Estudio prospectivo aleatorizado que incluyó pacientes sometidos a cirugía de cáncer rectal en un único centro. El momento de la retirada de la sonda urinaria se aleatorizó y se dividió en dos grupos: primeras 48 horas y después de 48 horas. Se compararon las tasas de retención urinaria y de nueva cateterización entre los pacientes con retirada precoz y tardía de la sonda. RESULTADOS: Se incluyeron 66 pacientes, con una mediana de edad de 60 años (31-88 años) y predominio del sexo masculino (n = 40, 60.9%). Se produjo retención urinaria tras la retirada de la sonda en 8 (12%). No hubo diferencias entre los dos grupos en cuanto a necesidad de nueva cateterización (14% frente a 10%, p = 0.63). Todos los pacientes que precisaron un nuevo cateterismo (n = 8) y fueron dados de alta con una sonda urinaria (n = 4) eran varones. CONCLUSIONES: La retirada precoz o tardía de la sonda no influye en la aparición de retención urinaria en pacientes intervenidos de cáncer de recto.

Necrotizing fasciitis of the thigh secondary to perforated rectal cancer: the sciatic foramen as a route for infective spread.

Necrotizing fasciitis (NF) is a potentially life-threatening surgical emergency. It is a rapidly progressive infection of soft tissues, and mortality is related to the degree of sepsis and the general condition of the patient. It is a rare condition that requires a rapid diagnosis and surgical treatment is aggressive debridement. There are a small number of reported cases of perforation of a rectal malignancy leading to NF of the thigh. We present a case with rectal cancer in which the sciatic foramen had provided a channel for the spread of pelvic infection into the thigh.

La fascitis necrotizante es una emergencia quirúrgica potencialmente mortal. Es una infección de tejidos blandos rápidamente progresiva y la mortalidad está relacionada con el grado de sepsis y el estado general del paciente. Es una condición poco común que requiere un diagnóstico rápido, y el tratamiento quirúrgico consiste en un desbridamiento agresivo. Existe un pequeño número de casos notificados de perforación de neoplasia maligna de recto que conduce a fascitis necrotizante del muslo. Presentamos un caso de cáncer de recto en el cual el foramen ciático fue el canal para la propagación de la infección pélvica al muslo.