Germinal mutations in the base excision repair (BER) gene MUTYH (MYH) have recently

The outcome of surgical treatment of rectal cancer is related to the completeness of mesorectal excision. It is a more discriminative prognostic factor than the classic tumour-node-metastasis (TNM) system.

Rationale and Objectives: To prospectively evaluate perfusion computed tomography (CT) for assessment of changes in tumor vascularity after chemoradiation therapy (CRT) in locally advanced rectal cancer and to analyze the correlation between baseline perfusion parameters and tumor response. Materials and Methods:Twenty patients with rectal cancer underwent baseline perfusion CT before CRT, and in 11 an examination after CRT was also performed. For each tumor, blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability-surface area product (PS) were quantified. The Mann-Whitney U test compared baseline perfusion parameters of responders and nonresponders and pre-and post-CRT measurements were compared by the Wilcoxon signed-rank test (P < .05 statistically significant for both tests).Results: Baseline BF was significantly lower (P = .013) and MTT was significantly higher (P = .006) in responders. Both were able to discriminate responders from nonresponders with a sensitivity of 80% and 100% and a specificity of 73.3% and 86.7%, respectively, for BF and MTT. Baseline BV and PS were not significantly different in responders and nonresponders. Perfusion parameters changed significantly in post-CRT scans compared to baseline: BF (P = .003), BV (P = .003), and PS (P = .008) decreased, whereas MTT increased (P = .006).Conclusion: Baseline BF and MTT can discriminate patients with a favorable response from those that fail to respond to CRT, potentially selecting high-risk patients with resistant tumors that may benefit from an aggressive preoperative treatment approach.

A large frequency of biallelic MYH mutations (69%) was found in APC mutation negative patients belonging to families with attenuated polyposis; the highest percentage was observed in families presenting evidence for horizontal transmission of the disease. The high percentage of degeneration found in these patients suggests that colonoscopy with polypectomies is not sufficient and prophylactic colectomy is recommended. The identification of MYH associated polyposis is important to evaluate the level of risk, particularly for the siblings.

Background and Aim: Enteral nutrition (EN) is applicable to adult Crohn’s disease (CD) in treating malnutrition and in inducing remission – here as a less effective alternative than corticosteroids. The purpose of this review is to determine whether preoperative EN impacts postoperative complications of adult CD, either by means of nutritional or therapeutic effects. Summary: A systematic review of English written full-text research articles published between January 1990 and November 2017, including adult patients undergoing abdominal surgery for complicated CD after EN, was performed. Four studies out of 22 were selected, all of which institutional, retrospective, case-control cohorts, one classified as “good quality” and three as “poor quality,” as rated by the Newcastle-Ottawa Scale. The application of inclusion and exclusion criteria resulted in a non-intentional absence of studies referring to supplemental EN among those reviewed. The reduced number of heterogeneous eligible studies impeded meta-analysis. In all studies, exclusive EN (EEN) was used and well tolerated, allowing to defer or even avoid surgery altogether, improving patients’ global state. The two studies with the greatest number of patients found preoperative EEN to be an independent factor against infectious and non-infectious complications in 219 patients and against anastomotic leaks or abscesses in 38 patients. Also, in univariate analysis, EEN was found to increase preop­erative immunosuppressant-free intervals and to protect against anastomotic dehiscences, intra-abdominal abscesses, surgical wound infections, ileus, stomas, and reoperations in the largest study; in another study it was related to fewer intra-abdominal septic complications. Key Messages: All reviewed studies are retrospective and, consequently, of limited relevance. Nonetheless, all of them call the attention of the scientific community to the potential benefits of preoperative EEN on postoperative outcomes in adult CD, calling for prospective multi-institutional studies and randomized controlled trials.