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Introduction: For locally advanced rectal cancers, in vivo radiological evaluation of tumor extent and regression after neoadjuvant therapy involves implicit visual identification of rectal structures on magnetic resonance imaging (MRI). Additionally, newer image-based, computational approaches (e.g., radiomics) require more detailed and precise annotations of regions such as the outer rectal wall, lumen, and perirectal fat. Manual annotations of these regions, however, are highly laborious and time-consuming as well as subject to inter-reader variability due to tissue boundaries being obscured by treatment-related changes (e.g., fibrosis, edema)., Methods: This study presents the application of U-Net deep learning models that have been uniquely developed with region-specific context to automatically segment each of the outer rectal wall, lumen, and perirectal fat regions on post-treatment, T 2 -weighted MRI scans., Results: In multi-institutional evaluation, region-specific U-Nets (wall Dice = 0.920, lumen Dice = 0.895) were found to perform comparably to multiple readers (wall inter-reader Dice = 0.946, lumen inter-reader Dice = 0.873). Additionally, when compared to a multi-class U-Net, region-specific U-Nets yielded an average 20% improvement in Dice scores for segmenting each of the wall, lumen, and fat; even when tested on T 2 -weighted MRI scans that exhibited poorer image quality, or from a different plane, or were accrued from an external institution., Discussion: Developing deep learning segmentation models with region-specific context may thus enable highly accurate, detailed annotations for multiple rectal structures on post-chemoradiation T 2 -weighted MRI scans, which is critical for improving evaluation of tumor extent in vivo and building accurate image-based analytic tools for rectal cancers., Competing Interests: SV has received research funding from Pfizer. The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article, or the decision to submit it for publication. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 DeSilvio, Antunes, Bera, Chirra, Le, Liska, Stein, Marderstein, Hall, Paspulati, Gollamudi, Purysko and Viswanath.)

(1) Background : The relatively poor expert restaging accuracy of MRI in rectal cancer after neoadjuvant chemoradiation may be due to the difficulties in visual assessment of residual tumor on post-treatment MRI. In order to capture underlying tissue alterations and morphologic changes in rectal structures occurring due to the treatment, we hypothesized that radiomics texture and shape descriptors of the rectal environment (e.g., wall, lumen) on post-chemoradiation T2-weighted (T2w) MRI may be associated with tumor regression after neoadjuvant chemoradiation therapy (nCRT). (2) Methods : A total of 94 rectal cancer patients were retrospectively identified from three collaborating institutions, for whom a 1.5 or 3T T2w MRI was available after nCRT and prior to surgical resection. The rectal wall and the lumen were annotated by an expert radiologist on all MRIs, based on which 191 texture descriptors and 198 shape descriptors were extracted for each patient. (3) Results : Top-ranked features associated with pathologic tumor-stage regression were identified via cross-validation on a discovery set ( n = 52, 1 institution) and evaluated via discriminant analysis in hold-out validation ( n = 42, 2 institutions). The best performing features for distinguishing low (ypT0-2) and high (ypT3-4) pathologic tumor stages after nCRT comprised directional gradient texture expression and morphologic shape differences in the entire rectal wall and lumen. Not only were these radiomic features found to be resilient to variations in magnetic field strength and expert segmentations, a quadratic discriminant model combining them yielded consistent performance across multiple institutions (hold-out AUC of 0.73). (4) Conclusions : Radiomic texture and shape descriptors of the rectal wall from post-treatment T2w MRIs may be associated with low and high pathologic tumor stage after neoadjuvant chemoradiation therapy and generalized across variations between scanners and institutions.

Unlabelled: Hospital length of stay (LOS) and readmissions continue to be expensive and unexpected events following colorectal surgery (CRS) whether patients follow enhanced recovery pathways or traditional care. Predictors of these adverse events could facilitate identification and optimization of CRS patients., The Aim of the Study: To examine the impact of white blood cell count (WBC) and C-reactive protein (CRP) levels as predictors of delayed recovery or hospital readmission following CRS., Material and Methods: Patients undergoing laparoscopic or open abdominal colorectal surgery by a single surgeon were managed using standardized enhanced recovery pathways. Those with postoperative day 2 CRP and white blood cell values were evaluated. Outcomes included 30-day hospital readmission rates and postoperative length of hospital stay., Results: CRP values were available for 193 patients (86 Male, mean age 58.6 years). Ninety-nine patients had surgery for colon cancer, 23 for Crohn's disease, 19 for ulcerative colitis, 31 for diverticulitis and 18 for other reasons. Twenty patients (10.4%) were readmitted to the hospital within 30 days of surgery. POD2 CRP accurately predicted short length of hospital stay (p< 0.01). Average CRP was 6.3 in the LOS of < 3 days or less, and 11.7 in patients with LOS >4 days. The mean CRP of the readmission and non-readmission groups was 11.8 and 9.9, respectively (p=0.29). The average POD 2 WBC of the readmission and non-readmission groups was 10.6 and 9 respectively (p=0.01)., Conclusion: A low POD2 CRP level was correlated with a shorter LOS, but it did not predict readmission. Conversely, POD2 WBC, and the difference in WBC from baseline were associated with readmission. These markers may be useful indicators to predict suitability of early discharge in an ERP. Further evaluation in prospective trials is warranted.

Purpose: Collagen anal fistula plug treatment of transsphincteric fistulas produces variable results. The purpose of our study was to determine whether long-tract fistulas (>4 cm) correlated with successful closure., Methods: All patients undergoing transsphincteric cryptoglandular fistula repair with anal fistula plugs were enrolled in a prospective database. Patients with Crohn's disease were excluded. Fistula tract length was measured intraoperatively by subtracting the remaining plug length from the original plug size. All procedures used standardized techniques and postoperative care pathways. The primary outcome was complete fistula closure assessed through both postoperative outpatient visits and a follow-up telephone questionnaire., Results: Forty-one patients with 42 fistula tracks were enrolled over a 39-month period. Complete closure was achieved in 18 of 42 (43%) fistulas at a mean follow-up of 25 months. Closure was not associated with gender, age, tract location, duration of seton, or length of follow-up. Successful closure was significantly associated with increased tract length, because fistulas longer than 4 cm were nearly 3 times more likely to heal compared with shorter fistulas ((14/23, 61%) vs (4/19, 21%), P = .004; relative risk = 2.8; 95% CI 1.14-7.03)., Conclusions: Anal fistula plug repair of cryptoglandular anorectal fistulas is more successful for long-tract fistulas. Although the overall success is modest, limiting surgical indications to fistulas exceeding 4 cm may maximize benefits of the plug technique.

Background: Laparoscopic colectomy has become the standard of care for elective resections; however, there are few data regarding laparoscopy in the emergency setting., Methods: By using a database with prospectively collected data, we identified 94 patients who underwent an emergency colectomy between August 2005 and July 2008. Laparoscopic surgeries were performed in 42 patients and were compared with 25 patients who were suitable for laparoscopy but received open colectomy., Results: The groups had similar demographics with no differences in age, sex, or surgical indications. Blood loss was lower (118 vs 205 mL; P < 0.01) and the postoperative stay was shorter (8 vs 11 d; P = 0.02) in the laparoscopic patients, and perioperative mortality rates were similar between the 2 groups (1 vs 3; P = 0.29)., Conclusions: With increasing experience, laparoscopic colectomy is a feasible option in certain emergency situations and is associated with shorter hospital stay, less morbidity, and similar mortality to that of open surgery.

Background: No specific scoring system exists for the assessment of postoperative quality of life (QOL) after major abdominal surgery. This study prospectively validates PQL, a novel prospective scoring system in patients having laparoscopic or open major abdominal colorectal surgery., Methods: Six experienced surgeons developed the questionnaire. Twenty patients reviewed and selected the most relevant questions, yielding 14 questions. One hundred patients undergoing a variety of colorectal procedures completed the questionnaire preoperatively, and on postoperative days (POD) 1, 2, 4, 8, 12, 30, and 60. Internal validation was assessed by Cronbach's alpha and factor analysis., Results: Cronbach's alpha revealed excellent internal consistency, ranging from .84 to .94 at all time points, even at POD 1 when Cronbach's alpha was .79, demonstrating that the items in the questionnaire measured the same underlying construct. Factor analysis consistently loaded at each follow-up time on the same 2 factors., Conclusions: Factor analysis consistently loaded at each follow-up time on the same 2 factors, designated the PQL Symptom Score and the PQL Recover Score.

The human iNOS (hiNOS) gene is expressed in a tissue-specific manner, but the molecular basis for this regulation has not been elucidated. Here, we show that liver cell-specific hiNOS gene activation involves protein-DNA binding to an A-activator binding site (AABS) located at -192 nucleotides in the hiNOS promoter region. Mutation of this site in the -7.2 kb hiNOS promoter construct inhibited basal hiNOS promoter activity in primary rat hepatocytes (77%), and two human liver cell lines, AKN-1 (63%) and HepG2 (60%), but had no significant effect on basal hiNOS activity in three non-hepatic human cell types. Interestingly, mutation of AABS significantly abrogated cytokine-induced promoter activity in all cell types. C/EBPbeta transcription factor bound to AABS by gel shift assay. Overexpression of C/EBPbeta active form (LAP) increased hiNOS basal promoter activity approximately sixfold in liver cells, but had minimal effect in non-hepatic cells. In contrast, overexpression of the transcriptional inhibitor (LIP) strongly suppressed both basal and cytokine-inducible promoter activity. These data show that the cis-acting AABS DNA element mediates liver-specific basal hiNOS promoter activity through binding of the trans-acting C/EBPbeta factor. Further, C/EBPbeta binding to AABS functions as a "switchpoint" that is necessary for cytokine-inducible hiNOS gene expression in all cell types examined.