RAS Mutation Decreases Overall Survival After Optimal Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy of Colorectal Peritoneal Metastasis: A Modification Proposal of the Peritoneal Surface Disease Severity Score.

BACKGROUND: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are currently the most accepted treatment for peritoneal metastases from colorectal cancer. Restrictive selection criteria are essential to obtain the best survival benefits for this complex procedure. The most widespread score for patient selection, the peritoneal surface disease severity score (PSDSS), does not include current biological factors that are known to influence on prognosis. We investigated the impact of including RAS mutational status in the selection criteria for these patients. METHODS: We studied the risk factors for survival by multivariate analysis using a prospective database of consecutive patients with carcinomatosis from colorectal origin treated by CRS and HIPEC in our unit from 2009 to 2017. The risk factors obtained were validated in a multicentre, international cohort, including a total of 520 patients from 15 different reference units. RESULTS: A total of 77 patients were selected for local análisis. Only RAS mutational status (HR: 2.024; p = 0.045) and PSDSS stage (HR: 2.90; p = 0.009) were shown to be independent factors for overall survival. Early PSDSS stages I and II associated to RAS mutations impaired their overall survival with no significant differences with PSDSS stage III overall survival (p > 0.05). These results were supported by the international multicentre validation. CONCLUSIONS: By including RAS mutational status, we propose an updated RAS-PSDSS score that outperforms PSDSS alone providing a quick and feasible preoperative assessment of the expected overall survival for patients with carcinomatosis from colorectal origin undergone to CRS + HIPEC.

Intestinal obstruction due to bezoars: a retrospective clinical study.

PURPOSE: The purpose of this study was to compare the results of surgical procedures applied to rare intestinal obstruction cases due to bezoars and to identify effective factors for determining the type of surgical procedure to be applied. METHODS: The records of 62 patients who had received gastrointestinal surgical treatment due to bezoars were assessed retrospectively. The preoperative characteristics, perioperative findings and postoperative results of cases that had and had not undergone an enterotomy were compared RESULTS: The average patient age was 57.7 years (range, 26-84 years), and all patients had phytobezoars, except one. The most common location for bezoars was the jejunum (28 cases, 45.1 %). Sixteen cases (25.8 %) had multiple bezoars located in different parts of the gastrointestinal tract. While milking was applied to 26 cases (41.9 %) with small intestinal bezoars, an enterotomy was used to remove bezoars in 23 cases (37 %). More complications tended to be identified in patients who underwent an enterotomy; however, the difference was not significant (p = 0.553). CONCLUSIONS: The frequency of previous abdominal surgery in patients suffering from an intestinal obstruction due to bezoars causes diagnostic conflict. The location of bezoars in the small intestine should also be considered when deciding the surgical procedure, as well as the physical properties of the bezoars. Our opinion is that conducting the milking procedure should not be insisted on, and that an enterotomy should be conducted when necessary.