Comparing three-dimensional endorectal ultrasound and magnification chromoendoscopy for early rectal neoplasia invasion depth assessment.

INTRODUCTION: Accurate assessment of invasion depth of early rectal neoplasms is essential for optimal therapy. We aimed to compare three-dimensional endorectal ultrasound (3D-ERUS) with magnification chromoendoscopy (MCE) regarding their accuracy in assessing parietal invasion depth (T). METHODS: Patients with middle and distal rectum neoplasms were prospectively included. Two providers blinded to each other's assessment performed 3D-ERUS and MCE, respectively. The T stage assessed through ERUS was compared to the MCE evaluation. The results were compared to the surgical specimen anatomopathological report. Sensitivity, specificity, accuracy, positive (PPV), and negative (NPV) predictive values were calculated for the T stage and for the final therapy (local excision or radical surgery). RESULTS: In 8 years, 70 patients were enrolled, and all underwent both exams. MCE and ERUS showed an accuracy of 94.3% and 85.7%, sensitivity of 83.7 and 93.3%, specificity of 96.4 and 83.6%, PPV of 86.7 and 60.9%, and NPV of 96.4 and 97.9%, respectively. Kappa for T stage assessed through ERUS was 0.64 and 0.83 for MCE. CONCLUSION: MCE and 3D-ERUS had good diagnostic performance, but the endoscopic method had higher accuracy. Both methods reliably assessed lesion extension, circumferential involvement, and distance from the anal verge.

Impact of a Routine Colorectal Endoscopic Submucosal Dissection in the Surgical Management of Nonmalignant Colorectal Lesions Treated in a Referral Cancer Center.

BACKGROUND: Recent data show an increasing number of abdominal surgeries being performed for the treatment of nonmalignant colorectal polyps in the West but in settings in which colorectal endoscopic submucosal dissection is not routinely performed. This study evaluated the number of nonmalignant colorectal lesions referred to surgical treatment in a tertiary cancer center that incorporated magnification chromoendoscopy and endoscopic submucosal dissection as part of the standard management of complex colorectal polyps. OBJECTIVE: The study aimed to estimate the number of patients with nonmalignant colorectal lesions referred to surgical resection at our institution after the standardization of routine endoscopic submucosal dissection and to describe outcomes for patients undergoing colorectal endoscopic submucosal dissection. DESIGN: Single-center retrospective study from a prospectively collected database of endoscopic submucosal dissections and colorectal surgeries performed between January 2016 and December 2019. SETTING: Reference cancer center. PATIENTS: Consecutive adult patients with complex nonmalignant colorectal polyps were included. INTERVENTIONS: Patients with nonmalignant colorectal polyps were treated by endoscopic submucosal dissection or surgery (elective colectomy, rectosigmoidectomy, low anterior resection, or proctocolectomy). MAIN OUTCOMES MEASURES: The primary outcome measure was the percentage of patients referred to colorectal surgery for nonmalignant lesions. RESULTS: In the study period, 1.1% of 825 colorectal surgeries were performed for nonmalignant lesions, and 97 complex polyps were endoscopically removed by endoscopic submucosal dissection. The en bloc, R0, and curative resection rates of endoscopic submucosal dissection were 91.7%, 83.5%, and 81.4%, respectively. The mean tumor size was 59 (SD 37.8) mm. Perforations during endoscopic submucosal dissection occurred in 3 cases, all treated with clipping. One patient presented with a delayed perforation 2 days after the endoscopic resection and underwent surgery. The mean follow-up period was 3 years, with no tumor recurrence in this cohort. LIMITATIONS: Single-center retrospective study. CONCLUSIONS: A workflow that includes assessment of the lesions with magnification chromoendoscopy and resection through endoscopic submucosal dissection can lead to a very low rate of abdominal surgery for nonmalignant colorectal lesions. See Video Abstract at http://links.lww.com/DCR/C123 . IMPACTO DE LA DISECCIN SUBMUCOSA ENDOSCPICA COLORRECTAL DE RUTINA EN EL MANEJO QUIRRGICO DE LESIONES COLORRECTALES NO MALIGNAS TRATADAS EN UN CENTRO ONCOLGICO DE REFERENCIA: ANTECEDENTES:Datos recientes muestran un número cada vez mayor de cirugías abdominales realizadas para el tratamiento de pólipos colorrectales no malignos en Occidente, pero no en los entornos donde la disección submucosa endoscópica colorrectal se realiza de forma rutinaria. El estudio evaluó el número de lesiones colorrectales no malignas referidas a tratamiento quirúrgico en un centro oncológico terciario, que incorporó cromoendoscopia de aumento y disección submucosa endoscópica como parte del manejo estándar de pólipos colorrectales complejos.OBJETIVO:Estimar el número de pacientes con lesiones colorrectales no malignas referidos para resección quirúrgica en nuestra institución, después de la estandarización de la disección submucosa endoscópica de rutina y describir los resultados para los pacientes sometidos a disección submucosa endoscópica colorrectal.DISEÑO:Estudio retrospectivo de un solo centro, a partir de una base de datos recolectada prospectivamente de disecciones submucosas endoscópicas y cirugías colorrectales realizadas entre enero de 2016 y diciembre de 2019.AJUSTE:Centro oncológico de referencia.PACIENTES:Pacientes adultos consecutivos con pólipos colorrectales no malignos complejos.INTERVENCIONES:Pacientes con pólipos colorrectales no malignos tratados mediante disección submucosa endoscópica o cirugía (colectomía electiva, rectosigmoidectomía, resección anterior baja o proctocolectomía).PRINCIPALES MEDIDAS DE RESULTADO:La medida de resultado primario fue el porcentaje de pacientes remitidos a cirugía colorrectal por lesiones no malignas.RESULTADOS:En el período, 1,1% de 825 cirugías colorrectales fueron realizadas por lesiones no malignas y 97 pólipos complejos fueron extirpados por. disección submucosa endoscópica. Las tasas de resección en bloque, R0 y curativa de disección submucosa endoscópica fueron 91,7%, 83,5% y 81,4%, respectivamente. El tamaño tumoral medio fue de 59 (DE 37,8) mm. Se produjeron perforaciones durante la disección submucosa endoscópica en 3 casos, todos tratados con clipaje. Un paciente presentó una perforación diferida 2 días después de la resección endoscópica y fue intervenido quirúrgicamente. El seguimiento medio fue de 3 años, sin recurrencia tumoral en esta cohorte.LIMITACIONES:Estudio retrospectivo de un solo centro.CONCLUSIONES:Un flujo de trabajo que incluye la evaluación de las lesiones con cromoendoscopia de aumento y resección a través de disección submucosa endoscópica, puede conducir a una tasa muy baja de cirugía abdominal para lesiones colorrectales no malignas. Consulte Video Resumen en http://links.lww.com/DCR/C123 . (Traducción-Dr. Fidel Ruiz Healy ).

Mucinous Degeneration on MRI After Neoadjuvant Therapy in Patients With Rectal Adenocarcinoma: Frequency and Association With Clinical Outcomes.

BACKGROUND. Patients with nonmucinous rectal adenocarcinoma may develop mucinous changes after neoadjuvant chemoradiotherapy, which are described as mucinous degeneration. The finding's significance in earlier studies has varied. OBJECTIVE. The purpose of this study was to assess the frequency of mucinous degeneration on MRI after neoadjuvant therapy for rectal adenocarcinoma and to compare outcomes among patients with nonmucinous tumor, mucinous tumor, and mucinous degeneration on MRI. METHODS. This retrospective study included 201 patients (83 women, 118 men; mean age, 61.8 ± 2.2 [SD] years) with rectal adenocarcinoma who underwent neoadjuvant chemoradiotherapy followed by total mesorectal excision from October 2011 to November 2015, underwent baseline and restaging rectal MRI examinations, and had at least 2 years of follow-up. Two radiologists independently evaluated MRI examinations for mucin content, which was defined as T2 hyperintensity in the tumor or tumor bed, and resolved differences by consensus. Patients were classified into three groups on the basis of mucin status: those with nonmucinous tumor (≤ 50% mucin content on baseline and restaging examinations), those with mucinous tumor (> 50% mucin content on baseline and restaging examinations), and those with mucinous degeneration (≤ 50% mucin content on baseline examination and > 50% content on restaging examination). The three groups were compared. RESULTS. Interreader agreement for mucin content, expressed as a kappa coefficient, was 0.893 on baseline MRI and 0.890 on restaging MRI. Of the 201 patients, 156 (77.6%) had nonmucinous tumor, 34 (16.9%) had mucinous tumor, and 11 (5.5%) had mucinous degeneration. Mucin status was not significantly associated with complete pathologic response (p = .41) or local or distant recurrence (both p > .05). The death rate during follow-up was not significantly different (p = .21) between patients with nonmucinous tumor (23.1%), those with mucinous tumor (29.4%), and those with mucinous degeneration (9.1%). In adjusted Cox regression analysis, with mucinous degeneration used as reference, the HR for the overall survival rate for the mucinous tumor group was 4.7 (95% CI, 0.6-38.3; p = .14), and that for the nonmucinous tumor group was 8.0 (95% CI, 0.9-59.9; p = .06). On histopathologic assessment, all 11 patients with mucinous degeneration showed acellular mucin, yet 10 of 11 patients showed viable tumor (i.e., in nonmucinous portions of the tumors). CONCLUSION. Mucinous degeneration on MRI is not significantly associated with pathologic complete response, recurrence, or survival. CLINICAL IMPACT. Mucinous degeneration on MRI is uncommon and should not be deemed an indicator of pathologic complete response.

Long-term outcomes of endoscopic submucosal dissection and transanal endoscopic microsurgery for the treatment of rectal tumors.

BACKGROUND AND AIM: Endoscopic submucosal dissection and transanal endoscopic microsurgery are good options for the treatment of rectal adenomas and early rectal carcinomas, but whether long-term outcomes of these procedures are comparable is not known. The aim of this study was to address this question. METHODS: A retrospective single-center study evaluating 98 consecutive procedures between June 2008 and December 2017 was performed in a tertiary cancer center. Consecutive patients who had undergone either endoscopic submucosal resection or transanal endoscopic microsurgery for rectal adenomas and early rectal carcinomas were evaluated, and long-term recurrence and complication rates were compared. RESULTS: Both groups were similar regarding sex, age, preoperative surgical risk, and en bloc resection rate (95.7% in the endoscopic and 100% in the surgical group, P = 0.81). Mean follow-up period was 37.6 months. Lesions resected endoscopically were significantly larger (68.5 mm) than those resected by transanal resection (44.5 mm), P = 0.003. Curative resections occurred in 97.2% of endoscopic resections and 85.2% of the surgical ones (P = 0.04). Comparing resections that fulfilled histologic curative criteria, there were no recurrences in the endoscopic group (out of 69 cases) and two recurrences in the transanal group (8.3% of 24 cases), P = 0.06. Late complications occurred in 12.7% of endoscopic procedures and 25.9% of surgical procedures (P = 0.13). CONCLUSIONS: In our experience, endoscopic submucosal resection seems to have advantages over transanal endoscopic microsurgery, with similar en bloc resection rate and lower rate of late complications and recurrences. Multicenter randomized controlled trials are needed to support our findings.

T≤2N0 TRG1-2 in Post-Chemoradiation Therapy MRI: What can it Predict?

BACKGROUND: Total mesorectal excision is the standard radical operation after neoadjuvant chemoradiotherapy for patients with middle/low locally advanced rectal cancer. However, it carries significant rates of morbidity, sexual/urinary dysfunction, fecal impairment and permanent stoma. The ability to identify patients with a complete or nearly-complete response could help steer patients to less-invasive surgery or a watch-and-wait strategy. OBJECTIVE: To assess the ability to predict good responders and a favorable prognosis among rectal cancer patients by post-chemoradiation therapy MRI. PATIENTS: Consecutive patients stage T3-4N0M0 or T(any)N+M0 located within 10cm from the anal verge were enrolled. Patients were staged and re-staged 8.8 weeks after the completion of chemoradiation by digital exam, colonoscopy, pelvic-MRI, and thorax and abdominal CT scans. All patients underwent total mesorectal excision with curative intent. RESULTS: Of the total 309 patients, 275 were eligible, and 199 (72.4%) of these were stage III. Restaging-MRI identified 59 (21.4%) T=2N0/TRG1-2. Specimen pathologic evaluation revealed 43 (15.6%) patients with a complete pathologic response. Estimates of the accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of MRIyT=2N0/TRG1-2 for the identification of ypT0N0 were 79.7%, 84.5%, 53.5%, 39%, and 90.7%, respectively. Estimates for the identification of ypN0 were 48.4%, 27.8%, 92%, 88.1%, and 48.4%, respectively. In a multivariate analysis, the only pre-CRT/MRI variables that were associated with an increased risk of lymph node involvement at the specimen were N+ (OR=2.22) and extramural vascular invasion (OR=2.28). MRI yT=2N0/TRG1-2 patients showed improved estimated 5-year disease-free survival, but no difference in estimated 5-year survival. CONCLUSION: Although MRIyT=2N0/TRG1-2 cannot predict all cases of a complete pathologic response, it can effectively predict a low rate of lymph node involvement and a better prognosis in patients who undergo total mesorectal excision.

Efficacy of 3-Dimensional Endorectal Ultrasound for Staging Early Extraperitoneal Rectal Neoplasms.

BACKGROUND: Adequate oncologic staging of rectal neoplasia is important for treatment and prognostic evaluation of the disease. Diagnostic methods such as endorectal ultrasound can assess rectal wall invasion and lymph node involvement. OBJECTIVE: The purpose of this study was to correlate findings of 3-dimensional endorectal ultrasound and pathologic diagnosis of extraperitoneal rectal tumors with regard to depth of rectal wall invasion, lymph node involvement, percentage of rectal circumference involvement, and tumor extension. DESIGN: Consecutive patients with extraperitoneal rectal tumors were prospectively assessed by 3-dimensional endorectal ultrasound blind to other staging methods and pathologic diagnosis. PATIENTS: Patients who underwent endorectal ultrasound followed by surgery were included in the study. SETTINGS: The study was conducted at a single academic institution. MAIN OUTCOME MEASURES: Sensitivity, specificity, positive and negative predictive values, area under curve, and κ coefficient between 3-dimensional endorectal ultrasound and pathologic diagnosis were determined. Intraclass correlation coefficient was calculated for tumor extension and percentage of rectal wall involvement. RESULTS: Forty-four patients (27 women; mean age = 63.5 years) were evaluated between September 2010 and June 2014. Most lesions were malignant (72.7%). For depth of submucosal invasion, 3-dimensional endorectal ultrasound showed sensitivity of 77.3%, specificity of 86.4%, positive predictive value of 85.0%, a negative predictive value of 79.2%, and an area under curve of 0.82. The weighted κ coefficient for depth of rectal wall invasion staging was 0.67, and there was no agreement between 3-dimensional endorectal ultrasound and pathologic diagnosis for lymph node involvement (κ = -0.164). Intraclass correlation coefficient for lesion extension and percentage of rectal circumference involvement were 0.45 and 0.66. A better correlation between 3-dimensional endorectal ultrasound and pathologic diagnosis was observed in tumors <5 cm and with <50% of rectal wall involvement. LIMITATIONS: The relatively small sample size of patients with early rectal lesions referred directly for surgery could represent a potential selection bias. CONCLUSIONS: Three-dimensional endorectal ultrasound was effective for determining rectal wall invasion and lesion extension in tumors <5 cm and with <50% of rectal wall invasion but was limited for detecting lymph node involvement in early rectal lesions.

Endoscopic colostomy with percutaneous colopexy: an animal feasibility study.

BACKGROUND: Indications for colostomy in colorectal diseases are obstruction of the large bowel, such as in cancer, diverticular disease in the acute phase, post-radiotherapy enteritis, complex perirectal fistulas, anorectal trauma and severe anal incontinence. Some critically ill patients cannot tolerate an exploratory laparotomy, and laparoscopic assisted colostomy also requires general anesthesia. OBJECTIVE: To evaluate the feasibility, safety and efficacy of performing colostomy assisted by colonoscopy and percutaneous colopexy. MATERIALS AND METHODS: Five pigs underwent endoscopic assisted colostomy with percutaneous colopexy. Animals were evaluated in post-operative days 1, 2, 5 and 7 for feeding acceptance and colostomy characteristics. On day 7 full colonoscopy was performed on animals followed by exploratory laparotomy. RESULTS: Average procedure time was 27 minutes (21-54 min). Postoperative mobility and feeding of animals were immediate after anesthesia recovery. Position of the colostomy, edges color, appearance of periostomal area, as well as its function was satisfactory in four animals. Retraction of colostomy was present in one pig. The colonoscopy and laparotomy control on the seventh day were considered as normal. A bladder perforation that was successfully repaired through the colostomy incision occurred in one pig. The main limitation of this study is its experimental nature. CONCLUSION: Endoscopic assisted colostomy with percutaneous colopexy proves to be a safe and effective method with low morbidity for performing colostomy in experimental animals, with possible clinical application in humans.

Pathologic Complete Response in Rectal Cancer: Can We Detect It? Lessons Learned From a Proposed Randomized Trial of Watch-and-Wait Treatment of Rectal Cancer.

BACKGROUND: Chemoradiotherapy has the potential to downsize and downstage tumors before surgery, decrease locoregional recurrence, and induce a complete sterilization of tumor cells for middle and low locally advanced rectal cancer. A watch-and-wait tactic has been proposed for patients with clinical complete response. OBJECTIVE: The purpose of this study was to verify our ability to identify complete clinical response in patients with rectal cancer based on clinical and radiologic criteria. DESIGN: This was a prospective study. SETTINGS: The study was conducted at a single institution, in the setting of a watch-and-wait randomized trial. PATIENTS: Consecutive patients with stage T3 to T4N0M0 or T(any)N+M0 cancer located within 10 cm from anal verge or T2N0 within 7 cm from anal verge were included in the study. Patients were staged and restaged 8 weeks after completion of chemoradiation (5-fluorouracil, 5040 cGy) by digital examination, colonoscopy, pelvic MRI, and thorax and abdominal CT scans. MAIN OUTCOME MEASURES: Clinical and radiologic judgments of tumor response were compared with pathologic response of patients treated by total mesorectal excision or clinical follow-up of patients selected for nonoperative treatment. RESULTS: A total of 118 patients were treated. Six patients were considered clinic complete responders (2 randomly assigned for surgery (1 ypT0N0 and 1 ypT2N0) and 4 patients randomly assigned for observation (3 sustained clinic complete response and 1 had tumor regrowth)). The 112 clinic incomplete responders underwent total mesorectal excision, and 18 revealed pathologic complete response. These 18 patients were not considered complete responders at restaging because they presented at least 1 of the following conditions: mucosal ulceration and/or deformity and/or substenosis of rectal lumen at digital rectal examination and colonoscopy (n = 16), ymrT1 to T4 (n = 16), ymrN+ (n = 2), involvement of circumferential resection margin on MRI (n = 3), extramural vascular invasion on MRI (n = 4), MRI tumor response grade 2 to 4 (n = 15), and pelvic side wall lymph node involvement on MRI (n = 1). Sensitivity for identification of ypT0N0 or sustained clinic complete response was 18.2%. LIMITATIONS: This study has a short follow-up and small sample size. Radiologists who reviewed the restaging examination were not blinded to the pretreatment stage. Only 1 radiologist read the images of each patient. CONCLUSIONS: Evaluation of clinic complete response according to current adopted criteria has low sensitivity because pathologic complete response more frequently presented as clinic incomplete response (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A221).

Postoperative complications in the treatment of rectal neoplasia by transanal endoscopic microsurgery: a prospective study of risk factors and time course.

PURPOSE: Transanal endoscopic microsurgery (TEM) is a safe and efficient minimally invasive treatment for rectal benign and early malignant neoplasia, but postoperative complications may be severe. We aimed to evaluate the risk factors related to the incidence, severity, and time course of postoperative complications of TEM. METHODS: This is a prospective study of postoperative complications in 53 patients (>18 years old) with benign or early rectal neoplasia who underwent TEM with curative intention or, for higher stages, palliation. Outcome measures included age, sex, American Society of Anesthesiologists score, neoadjuvant chemoradiotherapy, lesion height and size, pathologic margins, tumor histology, and suture type. RESULTS: Overall morbidity was 50 %. Temporary fecal incontinence was the most frequent complication (17.3 %). Complication rates of Clavien-Dindo grades I and II were 21.1 % and those of grades III and IV 3.8 %. Of patients with complications, more had lesions under the first rectal valve than over the first valve (61.54 % vs 38.46 %, p = 0.04). Patients submitted to chemoradiotherapy had a 24-fold greater chance of presenting grade II complications (p = 0.002). When the surgical defect was treated using the TEM device to perform the suture, the chance of having grade III complications was reduced 16-fold (p = 0.04). Fifty-three percent of complications occurred in the first 10 days and 95 % within 20 days. CONCLUSIONS: Postoperative complications after transanal endoscopic microsurgery for the treatment of rectal neoplasia are frequent, acceptable, and usually controllable with pharmacologic treatment. Over time the nature of complications is continuous, centered on the first 20 days after surgery.

Endoscopic submucosal dissection versus transanal endoscopic microsurgery for the treatment of early rectal cancer.

BACKGROUND: Endoscopic submucosal dissection (ESD) and transanal endoscopic microsurgery (TEM) are minimally invasive procedures that can be used to treat early rectal cancer. OBJECTIVE: The aim of this study was to compare clinical efficacy between ESD and TEM for the treatment of early rectal cancer. METHODS: Between July 2008 and August 2011, 24 patients with early rectal cancers were treated by ESD (11) or TEM (13) at the Cancer Institute of São Paulo University Medical School (São Paulo, Brazil). Data were analyzed retrospectively according to database and pathological reports, with respect to en bloc resection rate, local recurrence, complications, histological diagnosis, procedure time and length of hospital stay. RESULTS: En bloc resection rates with free margins were achieved in 81.8 % of patients in the ESD group and 84.6 % of patients in the TEM group (p = 0.40). Mean tumor size was 64.6 ± 57.9 mm in the ESD group and 43.9 ± 30.7 mm in the TEM group (p = 0.13). Two patients in the TEM group and one patient in the ESD group had a local recurrence. The mean procedure time was 133 ± 94.8 min in the ESD group and 150 ± 66.3 min in the TEM group (p = 0.69). Mean hospital stay was 3.8 ± 3.3 days in the ESD group and 4.08 ± 1.7 days in the TEM group (p = 0.81). LIMITATIONS: This was a non-randomized clinical trial with a small sample size and selection bias in treatment options. CONCLUSION: ESD and TEM are both safe and effective for the treatment of early rectal cancer.

LAPAROSCOPIC RIGHT AND LEFT COLECTOMY: WHICH PROVIDES BETTER POSTOPERATIVE RESULTS FOR ONCOLOGY PATIENTS?

BACKGROUND: The laparoscopic approach considerably reduced the morbidity of colorectal surgery when compared to the open approach. Among its benefits, we can highlight less intraoperative bleeding, early oral intake, lower rates of surgical site infection, incisional hernia, and postoperative pain, and earlier hospital discharge. AIMS: To compare the perioperative morbidity of right versus left colectomy for cancer and the quality of laparoscopic oncologic resection. METHODS: Retrospective analysis of patients submitted to laparoscopic right and left colctomy between 2006 and 2016. Postoperative complications were classified using the Clavien-Dindo scale, 30 days after surgery. RESULTS: A total of 293 patients were analyzed, 97 right colectomies (33.1%) and 196 left colectomies (66.9%). The averageage was 62.8 years. The groups were comparable in terms of age, comorbidities, body mass index, and the American Society of Anesthesiology (ASA) classification. Preoperative transfusion was higher in the right colectomy group (5.1% versus 0.4%, p=0.004, p<0.05). Overall, 233 patients (79.5%) had no complications. Complications found were grade I and II in 62 patients (21.1%) and grade III to V in 37 (12.6%). Twenty-three patients (7.8%) underwent reoperation. The comparison between left and right colectomy was not statistically different for operative time, conversion, reoperation, severe postoperative complications, and length of stay. The anastomotic leak rate was comparable in both groups(5.6% versus 2.1%, p=0.232, p>0.05). The oncological results were similar in both surgeries. In multiple logistic regression, ASA statistically influenced the worst results (≥ III; p=0.029, p<0.05). CONCLUSIONS: The surgical and oncological results of laparoscopic right and left colectomies are similar, making this the preferred approach for both procedures.

MRI-based radiomic score increased mrTRG accuracy in predicting rectal cancer response to neoadjuvant therapy.

PURPOSE: To develop a magnetic resonance imaging (MRI)-based radiomics score, i.e., "rad-score," and to investigate the performance of rad-score alone and combined with mrTRG in predicting pathologic complete response (pCR) in patients with locally advanced rectal cancer following neoadjuvant chemoradiation therapy. METHODS: This retrospective study included consecutive patients with LARC who underwent neoadjuvant chemoradiotherapy followed by surgery from between July 2011 to November 2015. Volumes of interest of the entire tumor on baseline rectal MRI and of the tumor bed on restaging rectal MRI were manually segmented on T2-weighted images. The radiologist also provided the ymrTRG score on the restaging MRI. Radiomic score (rad-score) was calculated and optimal cut-off points for both mrTRG and rad-score to predict pCR were selected using Youden's J statistic. RESULTS: Of 180 patients (mean age = 63 years; 60% men), 33/180 (18%) achieved pCR. High rad-score (> - 1.49) yielded an area under the curve (AUC) of 0.758, comparable to ymrTRG 1-2 which yielded an AUC of 0.759. The combination of high rad-score and ymrTRG 1-2 yielded a significantly higher AUC of 0.836 compared with ymrTRG 1-2 and high rad-score alone (p < 0.001). A logistic regression model incorporating both high rad-score and mrTRG 1-2 was built to calculate adjusted odds ratios for pCR, which was 4.85 (p < 0.001). CONCLUSION: Our study demonstrates that a rectal restaging MRI-based rad-score had comparable diagnostic performance to ymrTRG. Moreover, the combined rad-score and ymrTRG model yielded a significant better diagnostic performance for predicting pCR.

The Role of Probe-Based Confocal Laser Endomicroscopy (pCLE) in the Diagnosis of Sustained Clinical Complete Response Under Watch-and-Wait Strategy After Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Adenocarcinoma: a Score Validation.

BACKGROUND: Watch-and-wait strategy has been increasingly accepted for patients with clinical complete response (cCR) after multimodal treatment for locally advanced rectal adenocarcinoma. Close follow-up is essential to the early detection of local regrowth. It was previously demonstrated that probe-based confocal laser endomicroscopy (pCLE) scoring using the combination of epithelial and vascular features might improve the diagnostic accuracy of cCR. AIM: To validate the pCLE scoring system in the assessment of patients with cCR after neoadjuvant chemoradiotherapy (nCRxt) for advanced rectal adenocarcinoma. METHODS: Digital rectal examination, pelvic magnetic resonance imaging (MRI), and pCLE were performed in 43 patients with cCR, who presented either a scar (N = 33; 76.7%) or a small ulcer with no signs of tumor, and/or biopsy negative for malignancy (N = 10; 23.3%). RESULTS: Twenty-five (58.1%) patients were men, and the mean age was 58.4 years. During the follow-up, 12/43 (27.9%) patients presented local regrowth and underwent salvage surgery. There was an association between pCLE diagnostic scoring and final histological report (for patients who underwent surgical resection) or final diagnosis at the latest follow-up (p = 0.0001), while this association was not observed with MRI (p = 0.49). pCLE sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 66.7%, 93.5%, 80%, 88.9%, and 86%, respectively. MRI sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 66.7%, 48.4%, 66.7%, 78.9%, and 53.5%, respectively. CONCLUSIONS: pCLE scoring system based on epithelial and vascular features improved the diagnosis of sustained cCR and might be recommended during follow-up. pCLE might add some valuable contribution for identifying local regrowth. Trial Registration This protocol was registered at the Clinical Trials (ClinicalTrials.gov identifier NCT02284802).

A novel approach for the treatment of pelvic abscess: transrectal endoscopic drainage facilitated by transanal endoscopic microsurgery access.

BACKGROUND: Postoperative pelvic abscesses in patients submitted to colorectal surgery are challenging. The surgical approach may be too risky, and image-guided drainage often is difficult due to the complex anatomy of the pelvis. This article describes novel access for drainage of a pelvic collection using a minimally invasive natural orifice approach. METHODS: A 37 year-old man presented with sepsis due to a pelvic abscess during the second postoperative week after a Hartmann procedure due to perforated rectal cancer. Percutaneous drainage was determined by computed tomography to be unsuccessful, and another operation was considered to be hazardous. Because the pelvic fluid was very close to the rectal stump, transrectal drainage was planned. The rectal stump was opened using transanal endoscopic microsurgery (TEM) instruments. The endoscope was advanced through the TEM working channel and the rectal stump opening, accessing the abdominal cavity and pelvic collection. RESULTS: The pelvic collection was endoscopically drained and the local cavity washed with saline through the scope channel. A Foley catheter was placed in the rectal stump. The patient's recovery after the procedure was successful, without the need for further intervention. CONCLUSIONS: Transrectal endoscopic drainage may be an option for selected cases of pelvic fluid collection in patients submitted to Hartmann's procedure. The technique allows not only fluid drainage but also visualization of the local cavity, cleavage of multiloculated abscesses, and saline irrigation if necessary. The use of TEM instrumentation allows safe access to the peritoneal cavity.

ANORECTAL MANOMETRY STANDARD OF A BRAZILIAN POPULATION AT PRODUCTIVE AGE WITHOUT PELVIC FLOOR DISORDERS: A PROSPECTIVE VOLUNTEERED STUDY.

BACKGROUND: Due to the lack of normal standards of anorectal manometry in Brazil, data used are subject to normality patterns described at different nationalities. AIM: To determine the values and range of the parameters evaluated at anorectal manometry in people, at productive age, without pelvic floor disorders comparing the parameters obtained between male and female. METHODS: Prospective analysis of clinical data, such as gender, age, race, body mass index (BMI) and anorectal manometry, of volunteers from a Brazilian university reference in pelvic floor disorders. RESULTS: Forty patients were included, with a mean age of 45.5 years in males and 37.2 females (p=0.43). According to male and female, respectively in mmHg, resting pressures were similar (78.28 vs. 63.51, p=0.40); squeeze pressures (153.89 vs. 79.78, p=0.007) and total squeeze pressures (231.27 vs. 145.63, p=0.002). Men presented significantly higher values of anorectal squeeze pressures, as well as the average length of the functional anal canal (2.85 cm in male vs. 2.45 cm in female, p=0.003). CONCLUSIONS: Normal sphincter pressure levels in Brazilians differ from those used until now as normal literature standards. Male gender has higher external anal sphincter tonus as compared to female, in addition a greater extension of the functional anal canal.

Is it Safe to Perform Elective Colorectal Surgical Procedures during the COVID-19 Pandemic? A Single Institution Experience with 103 Patients.

OBJECTIVES: Since the outbreak of the novel coronavirus disease 2019 (COVID-19), all health services worldwide underwent profound changes, leading to the suspension of many elective surgeries. This study aimed to evaluate the safety of elective colorectal surgery during the pandemic. METHODS: This was a retrospective, cross-sectional, single-center study. Patients who underwent elective colorectal surgery during the COVID-19 pandemic between March 10 and September 9, 2020, were included. Patient data on sex, age, diagnosis, types of procedures, hospital stay, mortality, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) preoperative screening tests were recorded. RESULTS: A total of 103 colorectal surgical procedures were planned, and 99 were performed. Four surgeries were postponed due to positive preoperative screening for SARS-CoV-2. Surgical procedures were performed for colorectal cancer (n=90) and inflammatory bowel disease (n=9). Laparoscopy was the approach of choice for 43 patients (43.4%), 53 (53.5%) procedures were open, and 3 (3%) procedures were robotic. Five patients developed COVID-19 in the postoperative period, and three of them died in the intensive care unit (n=3/5, 60% mortality). Two other patients died due to surgical complications unrelated to COVID-19 (n=2/94, 2.1% mortality) (p<0.01). Hospital stay was longer in patients with SARS-CoV-2 infection than in those without (38.4 versushttps://doi.org/10.3 days, respectively, p<0.01). Of the 99 patients who received surgical care during the pandemic, 94 were safely discharged (95%). CONCLUSION: Our study demonstrated that elective colorectal surgical procedures may be safely performed during the pandemic; however, preoperative testing should be performed to reduce in-hospital infection rates, since the mortality rate due to SARS-CoV-2 in this setting is particularly high.

IS LAPAROSCOPIC REOPERATION FEASIBLE TO TREAT EARLY COMPLICATIONS AFTER LAPAROSCOPIC COLORECTAL RESECTIONS?

BACKGROUND: Recently, with the performance of minimally invasive procedures for the management of colorectal disorders, it was allowed to extend the indication of laparoscopy in handling various early and late postoperative complications. AIM: To present the experience with laparoscopic reoperations for early complications after laparoscopic colorectal resections. METHODS: Patients undergoing laparoscopic colorectal resections with postoperative surgical complications were included and re-treated laparoscopically. Selection for laparoscopic approach were those cases with early diagnosis of complications, hemodynamic stability without significant abdominal distention and without clinical comorbidities that would preclude the procedure. RESULTS: In four years, nine of 290 (3.1%) patients who underwent laparoscopic colorectal resections were re-approached laparoscopically. There were five men. The mean age was 40.67 years. Diagnoses of primary disease included adenocarcinoma (n=3), familial adenomatous polyposis (n=3), ulcerative colitis (n=1), colonic inertia (n=1) and chagasic megacolon (n=1). Initial procedures included four total proctocolectomy with ileal pouch anal anastomosis; three anterior resections; one completion of total colectomy; and one right hemicolectomy. Anastomotic dehiscence was the most common complication that resulted in reoperations (n=6). There was only one case of an unfavorable outcome, with death on the 40th day of the first approach, after consecutive complications. The remaining cases had favorable outcome. CONCLUSION: In selected cases, laparoscopic access may be a safe and minimally invasive approach for complications of colorectal resection. However, laparoscopic reoperation must be cautiously selected, considering the type of complication, patient's clinical condition and experience of the surgical team.

Surgical outcomes after preceptored laparoscopic colorectal surgery: results of a Brazilian preceptorship program.

BACKGROUND/AIMS: Safety of laparoscopic colectomy education methods remains unknown. This study aimed at comparing the outcomes of patients undergoing preceptored laparoscopic colectomy with patients operated on by the same preceptor. METHODOLOGY: A prospective analysis of 30 pre-ceptored operations performed by nine surgeons (PD group) between 2006 and 2008 was conducted. Data of 30 operations matched for diagnosis and surgery type conducted by the same preceptor (P group) were evaluated. RESULTS: Median age was 56.2 (26-80) and 55.2 (22-81) respectively in P and PD group (p = 0.804). Eleven (36.7%) were male in P group, 16 (53.3%) in PD group (p = 0.194). Preceptored operations were not significantly longer than operations performed by the preceptor (198 vs. 156 min)--p = 0.072. Length of hospital stay did not differ [4 days (3-12) in P group, and 5 (3-15) in PD group, p = 0.296]. Conversion occurred in 4 cases in PD and in 2 in P group (p = 0.389). Morbidity was similar (23.3% in P and 26.7% in PD group). One patient from P and two from PD group needed reoperation. No deaths occurred. CONCLUSIONS: Laparoscopic colorectal surgery preceptorship programs in surgeon learner's place are safe. Surgeons' introduction through basic and hands-on courses is required for skills acquisition needed to minimize adverse outcomes.

Transanal endoscopic microsurgery: indications, results and controversies.

Transanal endoscopic microsurgery (TEM) was introduced in 1983 as a minimally invasive technique allowing the resection of adenomas and early rectal carcinomas unsuitable for local or colonoscopic excision which would otherwise require major surgery. After 25 years, there is still much debate about the procedure. This article presents the TEM technique, indications, results and complications, focusing on its role in rectal cancer. The controversial points addressed include long-term results, TEM in high-risk T1 lesions, TEM associated with combined modality therapy (CMT) for invasive rectal cancer and salvage therapy after TEM. The future perspectives for TEM are promising and its association with CMT will probably expand the select group of patients who will benefit from the procedure.