Valor de la elastografía por patrones de colores en la reestadificación del cáncer de recto / Value of elastography by color patterns in the restaging of rectal cancer i: en

Introducción: La elastografía cualitativa por ecografía endoscópica es una técnica para examinar las propiedades elásticas de los tejidos, que puede distinguir la fibrosis del tumor mediante patrones de colores. Objetivo: Determinar el valor de la elastografía por patrones de colores en la reestadificación del cáncer de recto. Métodos: Se efectuó un estudio observacional y descriptivo (serie de casos) de 54 pacientes con cáncer de recto atendidos en el Centro Nacional de Cirugía de Mínimo Acceso, en La Habana, entre septiembre del 2018 y diciembre del 2022, a quienes se les realizó elastografía por ecografía endoscópica para la reevaluación del tumor. Para determinar el valor de dicha técnica se calculó la sensibilidad, la especificidad, los valores predictivos positivo y negativo, las razones de verosimilitud positiva y negativa, así como el índice de Youden. Se estableció la concordancia diagnóstica según el índice kappa y el estudio histológico de la muestra tomada fue el estándar de referencia. Resultados: La concordancia de la elastografía con el resultado anatomopatológico fue buena (κ=0,84). La especificidad y el índice de validez resultaron ser de 91,7 y 94,4 %, respectivamente; mientras que el valor predictivo negativo fue de 84,6 %. Los 16 pacientes con patrón elastográfico mixto (ye3) tenían tumor residual localizado en alguna de las capas de la pared del recto. El índice de Youden alcanzó valores cercanos a 1. Conclusiones: El valor de esta técnica radica en su especificidad diagnóstica y en el valor predictivo negativo al diferenciar la fibrosis del tumor residual en la pared rectal.

Introduction: The qualitative elastography by endoscopic echography is a technique to examine the elastic properties of tissues that can distinguish the fibrosis of the tumor by means of color patterns. Objective: To determine the value of elastography by color patterns in the reestadification of the rectum cancer. Methods: An observational and descriptive study (serial cases) of 54 patients with rectum cancer was carried out, who were assisted in the National Center of Minimum Access Surgery, in Havana, between September, 2018 and December, 2022 to whom elastography by endoscopic echography were carried out for the reevaluation of the tumor. To determine the value of this technique the sensibility, specificity, the predictive positive and negative values, the positive and negative true ratio, as well as the index of Youden were calculated. The diagnostic consistency was established according to the kappa index and the histologic study of the sample was the reference standard. Results: The elastography consistency with the pathologic result was good (ĸ=0.84). The specificity and the index of validity were 91.7 and 94.4%, respectively; while the negative predictive value was 84.6%. The 16 patients with mixed elastographic pattern (ye3) had residual tumor located in some of the layers of the rectum wall. The Youden index reached values close to 1. Conclusions: The value of this technique resides in its diagnostic specificity and negative predictive value when differentiating fibrosis from the residual tumor in the rectal wall.

Colorectal cancer statistics, 2023.

Colorectal cancer (CRC) is the second most common cause of cancer death in the United States. Every 3 years, the American Cancer Society provides an update of CRC statistics based on incidence from population-based cancer registries and mortality from the National Center for Health Statistics. In 2023, approximately 153,020 individuals will be diagnosed with CRC and 52,550 will die from the disease, including 19,550 cases and 3750 deaths in individuals younger than 50 years. The decline in CRC incidence slowed from 3%-4% annually during the 2000s to 1% annually during 2011-2019, driven partly by an increase in individuals younger than 55 years of 1%-2% annually since the mid-1990s. Consequently, the proportion of cases among those younger than 55 years increased from 11% in 1995 to 20% in 2019. Incidence since circa 2010 increased in those younger than 65 years for regional-stage disease by about 2%-3% annually and for distant-stage disease by 0.5%-3% annually, reversing the overall shift to earlier stage diagnosis that occurred during 1995 through 2005. For example, 60% of all new cases were advanced in 2019 versus 52% in the mid-2000s and 57% in 1995, before widespread screening. There is also a shift to left-sided tumors, with the proportion of rectal cancer increasing from 27% in 1995 to 31% in 2019. CRC mortality declined by 2% annually from 2011-2020 overall but increased by 0.5%-3% annually in individuals younger than 50 years and in Native Americans younger than 65 years. In summary, despite continued overall declines, CRC is rapidly shifting to diagnosis at a younger age, at a more advanced stage, and in the left colon/rectum. Progress against CRC could be accelerated by uncovering the etiology of rising incidence in generations born since 1950 and increasing access to high-quality screening and treatment among all populations, especially Native Americans.

Validation of an MRI-only planning workflow for definitive pelvic radiotherapy.

PURPOSE: Previous work on Magnetic Resonance Imaging (MRI) only planning has been applied to limited treatment regions with a focus on male anatomy. This research aimed to validate the use of a hybrid multi-atlas synthetic computed tomography (sCT) generation technique from a MRI, using a female and male atlas, for MRI only radiation therapy treatment planning of rectum, anal canal, cervix and endometrial malignancies. PATIENTS AND METHODS: Forty patients receiving radiation treatment for a range of pelvic malignancies, were separated into male (n = 20) and female (n = 20) cohorts for the creation of gender specific atlases. A multi-atlas local weighted voting method was used to generate a sCT from a T1-weighted VIBE DIXON MRI sequence. The original treatment plans were copied from the CT scan to the corresponding sCT for dosimetric validation. RESULTS: The median percentage dose difference between the treatment plan on the CT and sCT at the ICRU reference point for the male cohort was - 0.4% (IQR of 0 to - 0.6), and - 0.3% (IQR of 0 to - 0.6) for the female cohort. The mean gamma agreement for both cohorts was > 99% for criteria of 3%/2 mm and 2%/2 mm. With dose criteria of 1%/1 mm, the pass rate was higher for the male cohort at 96.3% than the female cohort at 93.4%. MRI to sCT anatomical agreement for bone and body delineated contours was assessed, with a resulting Dice score of 0.91 ± 0.2 (mean ± 1 SD) and 0.97 ± 0.0 for the male cohort respectively; and 0.96 ± 0.0 and 0.98 ± 0.0 for the female cohort respectively. The mean absolute error in Hounsfield units (HUs) within the entire body for the male and female cohorts was 59.1 HU ± 7.2 HU and 53.3 HU ± 8.9 HU respectively. CONCLUSIONS: A multi-atlas based method for sCT generation can be applied to a standard T1-weighted MRI sequence for male and female pelvic patients. The implications of this study support MRI only planning being applied more broadly for both male and female pelvic sites. Trial registration This trial was registered in the Australian New Zealand Clinical Trials Registry (ANZCTR) ( www.anzctr.org.au ) on 04/10/2017. Trial identifier ACTRN12617001406392.

Comparison of Synthetic Computed Tomography Generation Methods, Incorporating Male and Female Anatomical Differences, for Magnetic Resonance Imaging-Only Definitive Pelvic Radiotherapy.

PURPOSE: There are several means of synthetic computed tomography (sCT) generation for magnetic resonance imaging (MRI)-only planning; however, much of the research omits large pelvic treatment regions and female anatomical specific methods. This research aimed to apply four of the most popular methods of sCT creation to facilitate MRI-only radiotherapy treatment planning for male and female anorectal and gynecological neoplasms. sCT methods were validated against conventional computed tomography (CT), with regard to Hounsfield unit (HU) estimation and plan dosimetry. METHODS AND MATERIALS: Paired MRI and CT scans of 40 patients were used for sCT generation and validation. Bulk density assignment, tissue class density assignment, hybrid atlas, and deep learning sCT generation methods were applied to all 40 patients. Dosimetric accuracy was assessed by dose difference at reference point, dose volume histogram (DVH) parameters, and 3D gamma dose comparison. HU estimation was assessed by mean error and mean absolute error in HU value between each sCT and CT. RESULTS: The median percentage dose difference between the CT and sCT was <1.0% for all sCT methods. The deep learning method resulted in the lowest median percentage dose difference to CT at -0.03% (IQR 0.13, -0.31) and bulk density assignment resulted in the greatest difference at -0.73% (IQR -0.10, -1.01). The mean 3D gamma dose agreement at 3%/2 mm among all sCT methods was 99.8%. The highest agreement at 1%/1 mm was 97.3% for the deep learning method and the lowest was 93.6% for the bulk density method. Deep learning and hybrid atlas techniques gave the lowest difference to CT in mean error and mean absolute error in HU estimation. CONCLUSIONS: All methods of sCT generation used in this study resulted in similarly high dosimetric agreement for MRI-only planning of male and female cancer pelvic regions. The choice of the sCT generation technique can be guided by department resources available and image guidance considerations, with minimal impact on dosimetric accuracy.

Trends in the incidence of early-onset colorectal cancer in all 50 United States from 2001 through 2017.

BACKGROUND: The rate of change in the incidence of colorectal cancer (CRC) among persons younger than 50 years in the United States appears to vary by demographics, tumor location, and geography. This study analyzed data from all 50 states to examine recent changes in the incidence of CRC among persons younger than 50 years and to identify key subgroups with disproportionate risk. METHODS: Annual incidence rates for CRC, colon cancer, and rectal cancer in persons aged 20 to 49 years were extracted from the US Cancer Statistics for the period 2001-2017. Secular trends were examined overall and by age group, sex, race/ethnicity, stage, and state. Joinpoint regression was used to compute annual percent changes and average annual percent changes (AAPCs) as well as corresponding 95% confidence intervals (95% CIs). RESULTS: The incidence of CRC increased by 1.27% (95% CI, 0.95%-1.60%) annually from 2001 to 2012 and by 3.00% (95% CI, 2.06%-3.95%) annually from 2012 to 2017. AAPCs for the period 2001-2017 were higher among persons aged 20 to 24 years (AAPC, 6.62%; 95% CI, 3.86%-9.45%) in comparison with other age groups and higher among non-Hispanic Whites (AAPC, 2.38%; 95% CI, 1.98%-2.79%) in comparison with other racial/ethnic groups. In 2001-2002, only 1 state had an age-standardized incidence rate > 13.0 per 100,000, but this number increased to 32 states by 2016-2017. CONCLUSIONS: CRC rates among US adults aged 20 to 49 years increased from 2001 to 2017, with the fastest increases observed from 2012 to 2017. Increases were observed among the youngest age groups, among non-Hispanic Whites, and in states in the West, Midwest, and Rocky Mountain regions. Increasing rates across all tumor stages suggest a real increase in CRC incidence.

Colorectal cancer statistics, 2020.

Colorectal cancer (CRC) is the second most common cause of cancer death in the United States. Every 3 years, the American Cancer Society provides an update of CRC occurrence based on incidence data (available through 2016) from population-based cancer registries and mortality data (through 2017) from the National Center for Health Statistics. In 2020, approximately 147,950 individuals will be diagnosed with CRC and 53,200 will die from the disease, including 17,930 cases and 3,640 deaths in individuals aged younger than 50 years. The incidence rate during 2012 through 2016 ranged from 30 (per 100,000 persons) in Asian/Pacific Islanders to 45.7 in blacks and 89 in Alaska Natives. Rapid declines in incidence among screening-aged individuals during the 2000s continued during 2011 through 2016 in those aged 65 years and older (by 3.3% annually) but reversed in those aged 50 to 64 years, among whom rates increased by 1% annually. Among individuals aged younger than 50 years, the incidence rate increased by approximately 2% annually for tumors in the proximal and distal colon, as well as the rectum, driven by trends in non-Hispanic whites. CRC death rates during 2008 through 2017 declined by 3% annually in individuals aged 65 years and older and by 0.6% annually in individuals aged 50 to 64 years while increasing by 1.3% annually in those aged younger than 50 years. Mortality declines among individuals aged 50 years and older were steepest among blacks, who also had the only decreasing trend among those aged younger than 50 years, and excluded American Indians/Alaska Natives, among whom rates remained stable. Progress against CRC can be accelerated by increasing access to guideline-recommended screening and high-quality treatment, particularly among Alaska Natives, and elucidating causes for rising incidence in young and middle-aged adults.

Cancer screening in the United States, 2019: A review of current American Cancer Society guidelines and current issues in cancer screening.

Each year, the American Cancer Society publishes a summary of its guidelines for early cancer detection, data and trends in cancer screening rates, and select issues related to cancer screening. In this issue of the journal, the current American Cancer Society cancer screening guidelines are summarized, and the most current data from the National Health Interview Survey are provided on the utilization of cancer screening for men and women and on the adherence of men and women to multiple recommended screening tests.

Colorectal cancer statistics, 2017.

Colorectal cancer (CRC) is one of the most common malignancies in the United States. Every 3 years, the American Cancer Society provides an update of CRC incidence, survival, and mortality rates and trends. Incidence data through 2013 were provided by the Surveillance, Epidemiology, and End Results program, the National Program of Cancer Registries, and the North American Association of Central Cancer Registries. Mortality data through 2014 were provided by the National Center for Health Statistics. CRC incidence rates are highest in Alaska Natives and blacks and lowest in Asian/Pacific Islanders, and they are 30% to 40% higher in men than in women. Recent temporal patterns are generally similar by race and sex, but differ by age. Between 2000 and 2013, incidence rates in adults aged ≥50 years declined by 32%, with the drop largest for distal tumors in people aged ≥65 years (incidence rate ratio [IRR], 0.50; 95% confidence interval [95% CI], 0.48-0.52) and smallest for rectal tumors in ages 50 to 64 years (male IRR, 0.91; 95% CI, 0.85-0.96; female IRR, 1.00; 95% CI, 0.93-1.08). Overall CRC incidence in individuals ages ≥50 years declined from 2009 to 2013 in every state except Arkansas, with the decrease exceeding 5% annually in 7 states; however, rectal tumor incidence in those ages 50 to 64 years was stable in most states. Among adults aged <50 years, CRC incidence rates increased by 22% from 2000 to 2013, driven solely by tumors in the distal colon (IRR, 1.24; 95% CI, 1.13-1.35) and rectum (IRR, 1.22; 95% CI, 1.13-1.31). Similar to incidence patterns, CRC death rates decreased by 34% among individuals aged ≥50 years during 2000 through 2014, but increased by 13% in those aged <50 years. Progress against CRC can be accelerated by increasing initiation of screening at age 50 years (average risk) or earlier (eg, family history of CRC/advanced adenomas) and eliminating disparities in high-quality treatment. In addition, research is needed to elucidate causes for increasing CRC in young adults. CA Cancer J Clin 2017. © 2017 American Cancer Society. CA Cancer J Clin 2017;67:177-193. © 2017 American Cancer Society.

Recent advances in delineation of clinical target volume in radiotherapy for rectal cancer / 中华放射肿瘤学杂志

The delineation of clinical target volume (CTV) is a critical step in planning conformal radiotherapy for rectal cancer.Several guidelines suggest different subvolumes and anatomical boundaries in radiotherapy for rectal cancer, potentially leading to a misunderstanding of CTV definition.This article reviews recent advances in the delineation of CTV in radiotherapy for rectal cancer.

Cancer screening in the United States, 2016: A review of current American Cancer Society guidelines and current issues in cancer screening.

Each year the American Cancer Society (ACS) publishes a summary of its guidelines for early cancer detection, data and trends in cancer screening rates, and select issues related to cancer screening. In this issue of the journal, we summarize current ACS cancer screening guidelines, including the update of the breast cancer screening guideline, discuss quality issues in colorectal cancer screening and new developments in lung cancer screening, and provide the latest data on utilization of cancer screening from the National Health Interview Survey.

Recent advances in preoperative intensity-modulated radiation therapy ( IMRT) for rectal cancer / 中华放射肿瘤学杂志

More than 20 studies published during the past 10 years concerning preoperative radiotherapy in rectal cancer were reviewed carefully. And we evaluated the role of IMRT being routinely used in preoperative treatment of rectal cancer.

A prognostic analysis of patients with pathologic complete response after preoperative neoadjuvant chemoradiotherapy for locally advanced rectal cancer / 中华放射肿瘤学杂志

Objective To analyze the clinical factors for pathologic complete response ( pCR) after preoperative neoadjuvant chemoradiotherapy ( neo?CRT) for locally advanced rectal cancer. Methods From 2005 to 2012, 297 patients with locally advanced rectal cancer and complete clinical data were enrolled as subjects. Those patients were diagnosed with biopsy and treated with neo?CRT ( radiotherapy by 3?dimonsional conformal radiotherapy or volumetric?modulated arc therapy) followed by radical surgery. The logistic regression model was used for the multivariate analyses of the correlation of pCR with age, gender, distance between tumor and the anal verge, serum level of carcinoembryonic antigen ( CEA ) before treatment, hemoglobin level before treatment, cT staging, and cN staging. Results In all patients, 78 ( 26?7%) patients had pCR after treatment. The numbers of patients with pCR were 42( 34?4%) in patients with stage T1?T3 disease and 37(21?1%) in patients with stage T4 disease. In the patients with serum CEA levels no higher than 5?33 ng/ml, 55(36?4%) had pCR after treatment, while in the patients with serum CEA levels higher than 5?33 ng/ml, only 24( 16?4%) had pCR. The univariate analysis revealed that age, gender, distance between tumor and the anal verge, anemia before treatment, or cN staging were not related to pCR. The multivariate analysis showed that stage cT1?T3 and a serum CEA level no higher than 5?33 ng/ml before treatment were influencing factors for pCR after neo?CRT for locally advanced rectal cancer ( P=0?031,P=0?000) . Conclusions The clinical staging and the serum CEA level before treatment are influencing factors for pCR after neo?CRT for locally advanced rectal cancer. The serum CEA level before treatment can be considered as a predictor of pCR after neo?CRT for locally advanced rectal cancer.

Colorectal cancer statistics, 2014.

Colorectal cancer is the third most common cancer and the third leading cause of cancer death in men and women in the United States. This article provides an overview of colorectal cancer statistics, including the most current data on incidence, survival, and mortality rates and trends. Incidence data were provided by the National Cancer Institute's Surveillance, Epidemiology, and End Results program and the North American Association of Central Cancer Registries. Mortality data were provided by the National Center for Health Statistics. In 2014, an estimated 71,830 men and 65,000 women will be diagnosed with colorectal cancer and 26,270 men and 24,040 women will die of the disease. Greater than one-third of all deaths (29% in men and 43% in women) will occur in individuals aged 80 years and older. There is substantial variation in tumor location by age. For example, 26% of colorectal cancers in women aged younger than 50 years occur in the proximal colon, compared with 56% of cases in women aged 80 years and older. Incidence and death rates are highest in blacks and lowest in Asians/Pacific Islanders; among males during 2006 through 2010, death rates in blacks (29.4 per 100,000 population) were more than double those in Asians/Pacific Islanders (13.1) and 50% higher than those in non-Hispanic whites (19.2). Overall, incidence rates decreased by approximately 3% per year during the past decade (2001-2010). Notably, the largest drops occurred in adults aged 65 and older. For instance, rates for tumors located in the distal colon decreased by more than 5% per year. In contrast, rates increased during this time period among adults younger than 50 years. Colorectal cancer death rates declined by approximately 2% per year during the 1990s and by approximately 3% per year during the past decade. Progress in reducing colorectal cancer death rates can be accelerated by improving access to and use of screening and standard treatment in all populations.

The expression of N-cadherin and vimentin in rectum adenocarcinoma and their clinical value / 重庆医学

Objective To observe the expression of neuronal cadherin (N-cadherin) and vimentin in primary rectum adenocarci-noma tissues and their clinical value .Methods 58 cases of primary rectum adenocarcinoma tissues after surgical resection and con-firmed by pathology ,and normal rectum tissues that at lest 5 cm away from the tumor were selected .The immunohistochemical SP method was used to detect the expression of N-cadherin and vimentin and analyzed their correlation .Results In rectum adenocarci-noma tissues ,the positive expression rate of N-cadherin and vimentin[53 .4% (31/58) ,46 .6% (27/58)]were significantly higher than those of in normal rectum mucosa tissues[3 .4% (2/58) ,1 .7% (1/58)] ,(P0 .05) .Conclusion N-cadherin and vim-entin have close relationships with metastasis of rectum adenocarcinoma ,to detect the expressions of N-cadherin and vimentin is of a effective method to judge the metastasis and prognosis of rectum adenocarcinoma .

Protocolo eletrônico de coleta de dados clínicos da microcirurgia endoscópica transanal (TEM): desenvolvimento e aplicação / Electronic protocol of clinical data collection in transanal endoscopic microsurgery (TEM): development and application

INTRODUÇÃO: A coleta de dados na forma prospectiva melhora a assistência ao paciente e o acesso à informação. Os registros feitos em prontuários de papel geralmente não trazem informação satisfatória, pois os dados acabam sendo perdidos ou não coletados adequadamente. A informática na saúde possibilita o melhor uso da informação, servindo, inclusive, como suporte para pesquisas científicas. OBJETIVOS: 1 - Criar, informatizar e armazenar uma base de dados clínicos da Microcirurgia Endoscópica Transanal (TEM), incorporando-a ao SINPE© e realizando coleta de dados; 2 - apresentar estudo descritivo dos resultados da coleta de dados realizada em 59 pacientes submetidos a TEM. MÉTODOS: Primeiro foi realizada a criação da base teórica de dados da TEM, que foi a seguir informatizada e incorporando-a ao SINPE© e realizou-se a coleta de dados. Segundo, efetuou-se estudo descritivo com interpretação das informações obtidas através de estatísticas e gráficos pelo módulo SINPE©Analisador. RESULTADOS: A utilização do software possibilitou a criação do protocolo da TEM. Os dados armazenados pela coleta de 59 pacientes submetidos ao procedimento cirúrgico foram resgatados e analisados pelo módulo SINPE Analisador©, gerando gráficos e estudos descritivos automaticamente. Verificou-se que 74,55 por cento (41) dos pacientes apresentavam, antes do procedimento operatório, o diagnóstico de adenoma. No estadiamento pré-operatório realizado por ultrassonografia transrretal, notou-se que a maioria dos tumores apresentaram estadiamento pré-operatório de adenoma (uT0). Em relação ao acometimento linfonodal dois foram avaliados no ultrassom como comprometidos. Quanto à profundidade de ressecção da parede retal verificou-se que mais de 60 por cento dos pacientes submetidos à TEM realizaram ressecção em bloco de toda a parede retal, ou seja, até a gordura perirretal. Verificou-se, que o número total de pacientes portadores de adenocarcinoma foi maior no estudo histopatológico...

BACKGROUND: Prospective data collection improves patient care and information access. Written medical records frequently are not well done, due to bad collected data associated to the risk of loosing important items. The use of computer technology in health care system provides better information. OBJECTIVES: To create, computerize and store a clinical database to Transanal Endoscopic Microsurgery (TEM), and it´s incorporation into SINPE© software; to present a descriptive study from 59 patients submitted to TEM. METHODS: Initially was created an Word® questionnaire containing all clinical data concerning to TEM; afterwards, this base was computerized and incorporated into SINPE© and, then, data started to be collected. Later, a descriptive study was done using the database with statistic analysis generated through SINPE©Analisador module. Finally, datamining studies verified patterns and tendencies which could not be visualized from simple data collection. RESULTS: The software allowed creation of TEM protocol. The data stored by collecting 59 patients undergoing the surgical procedure were recovered and analyzed by SINPE©Analisador module, generating charts and statistic automatically. It was found that 74.55 percent (41) of the patients presented with the diagnosis of adenoma before the surgical procedure. Preoperative staging conducted by transrectal ultrasonography defined most tumors as adenomas (uT0). Ultrasound identified that two lymph nodes were involved. With regard to the depth of the rectal wall resection, it was found that over 60 percent of the patients who underwent TEM had a full-thickness resection of all rectal wall, i.e., up to the peri-rectal fat. The total number of adenocarcinoma patients was greater in the histopathological study of the surgical specimen than in the preoperative biopsy. The results for the histopathological staging of the surgical specimen revealed differences between pre- and postoperative staging...

Rectal Teratoma coexistent with an Ovarian Teratoma: A Case Report

We report a case of rectal teratoma coexistent with an ovarian teratoma. To our knowledge, this is the first radiologic report of rectal teratoma. Computed tomography (CT) showed a sharply demarcated cystic and fatty mass with amorphous calcification in the rectum. A double-contrast barium study showed a well-defined intraluminal rectal mass without mucosal destruction. Imaging findings of rectal teratoma allow for correct preoperative diagnosis. CT was helpful in differentiating rectal teratoma from other rectal lesions.

Assessment of the Prognostic Factors for a Local Recurrence of Rectal Cancer: the Utility of Preoperative MR Imaging

OBJECTIVE: To determine the utility of MR imaging in evaluating the prognostic factors for a local recurrence of rectal cancer following a curative resection. MATERIALS AND METHODS: The preoperative MR images obtained from 17 patients with a local recurrence and 54 patients without a local recurrence, who had undergone a curative resection, were independently evaluated by three radiologists. The following findings were analyzed: the direct invasion of the perirectal fat by the primary rectal carcinoma, involvement of the perirectal lymph nodes, perirectal spiculate nodules, perivascular encasement, and an enlargement of the pelvic wall lymph nodes. The clinical and surgical profiles were obtained from the patients' medical records. The association of a local recurrence with the MR findings and the clinicosurgical variables was statistically evaluated. RESULTS: Of the MR findings, the presence of perivascular encasement (p = 0.001) and perirectal spiculate nodules (p = 0.001) were found to be significant prognostic factors for a local recurrence. Of the clinicosurgical profiles, the presence of a microscopic vascular invasion (p = 0.005) and the involvement of the regional lymph nodes (p = 0.006) were associated with a local recurrence. Logistic regression analysis showed that the presence of perirectal spiculate nodules was an independent predictor of a local recurrence (odds ratio, 7.382; 95% confidence interval, 1.438, 37.889; p = 0.017). CONCLUSION: The presence of perirectal spiculate nodules and perivascular encasement on the preoperative MR images are significant predictors of a local recurrence after curative surgery for a rectal carcinoma. This suggests that preoperative MR imaging can provide useful information to help in the planning of preoperative adjuvant therapy.

Follow-up Results After Negative Findings on Unenhanced Hepatic MR Imaging for Hepatic Metastasis from Rectal Cancer

OBJECTIVE: To assess the follow-up results after negative findings on unenhanced hepatic MR imaging in rectal cancer patients who have undergone locally curative surgery. MATERIALS AND METHODS: From all pertinent imaging reports and medical records, we selected 255 patients who had negative results on unenhanced hepatic MR imaging. When selecting patients who had undergone curative resection, the following patients were excluded from the study: 1) patients in whom extrahepatic metastases were detected on preoperative staging work-ups, 2) patients in whom the surgery was judged to be non-curative due to peritoneal seeding or local aggressiveness. Cases with follow-up periods of less than 18 months were also excluded, as these cases were considered insufficient to confirm the negative outcomes. Thus, a total of 149 patients were ultimately enrolled in our study. The follow-up results of unenhanced MR imagings were assessed according to the assumption that the newly developed hepatic metastases had been false-negative lesions on preoperative MR image. RESULTS: During a median follow-up period of 29.3 months, 25 hepatic metastases were detected in 13 patients (8.7%), which indicated a negative predictive value of 91.3%. CONCLUSION: Unenhanced hepatic MR imaging provides a high negative predictive value with regard to the detection of hepatic metastasis in the preoperative evaluation of rectal cancer.

CT Findings and Clinical Characteristics of Colorectal Mucinous Adenocarcinoma

PURPOSE: To establish the CT findings and clinical characteristics of colorectal mucinous adenocarcinoma. MATERIALS AND METHODS: The CT features of 26 surgically proven cases of colorectal mucinous adenocarcinoma were reviewed. The subjects were selected from among 262 patients with colorectal cancer, of whom 40 with non-mucinous adenocarcinoma were included as a control group. Contrast-enhaneed CT images were analyzed for tumor location, the presence or absence of tumoral calcification, tumor shape (circumferential or eccentric, polypoid or infiltrative), tumor thickness-to-length ratio, and attenuation and homogeneity. In each group, the TNM stage of pathologic specimens was compared. During follow-up, the incidence of recurrence, and outcome, were also compared. RESULTS: CT images of mucinous adenocarcinoma revealed intratumoral calcification in three patients (12%, p < 0.01). Tumors were eccentric and polypoid-shaped, with a high tumoral thickness/length ratio (p < 0.01). On contrast-enhanced images, most were seen as a heterogenous hypoattenvuted mass. No differences in T-NM stage were found in surgical specimens. In patients with mucinous adenocarcinoma, recurrence during the early follow-up period is more common than in patients with non-mucinous cancer. CONCLUSION: Contrast-enhanced CT reveals mucinous adenocarcinoma as an eccentric polypoid mass with heterogeneous hypoattenuation. In patients with mucinous colorectal cancer, careful follow-up is required because tumors tend to recur early in the follow-up period.

CT Findings and Clinical Characteristics of Colorectal Mucinous Adenocarcinoma

PURPOSE: To establish the CT findings and clinical characteristics of colorectal mucinous adenocarcinoma. MATERIALS AND METHODS: The CT features of 26 surgically proven cases of colorectal mucinous adenocarcinoma were reviewed. The subjects were selected from among 262 patients with colorectal cancer, of whom 40 with non-mucinous adenocarcinoma were included as a control group. Contrast-enhaneed CT images were analyzed for tumor location, the presence or absence of tumoral calcification, tumor shape (circumferential or eccentric, polypoid or infiltrative), tumor thickness-to-length ratio, and attenuation and homogeneity. In each group, the TNM stage of pathologic specimens was compared. During follow-up, the incidence of recurrence, and outcome, were also compared. RESULTS: CT images of mucinous adenocarcinoma revealed intratumoral calcification in three patients (12%, p < 0.01). Tumors were eccentric and polypoid-shaped, with a high tumoral thickness/length ratio (p < 0.01). On contrast-enhanced images, most were seen as a heterogenous hypoattenvuted mass. No differences in T-NM stage were found in surgical specimens. In patients with mucinous adenocarcinoma, recurrence during the early follow-up period is more common than in patients with non-mucinous cancer. CONCLUSION: Contrast-enhanced CT reveals mucinous adenocarcinoma as an eccentric polypoid mass with heterogeneous hypoattenuation. In patients with mucinous colorectal cancer, careful follow-up is required because tumors tend to recur early in the follow-up period.