Factors Influencing Anterior/Low Anterior Resection Syndrome after Rectal or Sigmoid Resections Abstract Purpose: Sphincter preserving surgery is one of the main goals in the treatment of rectal cancer because it improves the quality of life (QoL). However, some patients may experience disrupted symptoms called anterior or low anterior resection syndrome (LARS). This study designed to evaluate the frequency and influencing factors of LARS in patients who had undergone sigmoid or rectal resection. In this retrospective, clinical study, patients who had undergone rectal or sigmoid resection and anastomosis due to any benign and malignant reasons were evaluated in terms of LARS between January 2010 and November 2019 at Mersin University Medical Faculty Hospital. The frequency and severity of LARS determined by using routine LARS scale and influencing factor; including lesion localization, operation, the proximity of anastomosis to the anal verge, creation of stoma, chemotherapy, radiotherapy application were also investigated. A total of 276 of 550 patients included in this study. The major LARS incidence was found as 27.2%. Very low anterior resection (VLAR) , (OR=42.40 (95% CI [11.14-161.36], p<0.0001), protective ileostomy (OR=12.83 (95% CI [6.58-25.0], p<0.0001) end colostomy (OR=8.55 (95% CI [1.36-53.61], p=0.022), receiving chemotherapy (OR=3.08 (95% CI [1.71-5.53], p<0.0001) and radiotherapy (OR=2.51 (95% CI [1.38-4.57], p=0.003) and the ROC analysis showed that making an anastomosis below 8.5 cm from anal verge were found to be major influencing factors on LARS (p <0.05). LARS may frequently occur in patients who had undergone rectal resection. The most important factors influencing LARS were found as proximity of anastomosis to the anal canal and creating the protective stoma. Receiving chemoradiotherapy also plays an important role in LARS.

Objective: Despite being routinely used before elective colorectal surgery in most surgical clinics, mechanical bowel preparation (MBP) remains controversial. This study aimed to investigate postoperative complications and outcomes of right, left, or rectosigmoid resection without MBP. Material and Methods: Patients who underwent elective colorectal surgery without mechanical bowel preparation and oral antibiotics between January 2011 and December 2021 were included in the study. Patients were categorized according to the side of resection, and these subgroups were compared for anastomotic leakage, surgical site infections (SSI), and overall morbidity measured using the Clavien-Dindo complication grade. Results: Data of 422 patients were analyzed. Overall anastomotic leakage was found in 14 patients (3.3%), SSI in 46 (10.9%), collection in 14 (3.3%), mortality in 18 (4.3%), and reoperation in 17 (%4) patients. Anastomotic leakage was observed in six (3.9%) in right colectomy, two (1.9%) in left colectomy, and in six (3.7%) patients in the rectosigmoid resection group when the groups were evaluated separately. There was no statistical difference between the groups (p= 0.630). Furthermore, there was no statistical difference between the groups regarding collection and reoperation (p values were p= 0.31, and p= 0.251, respectively). Conclusion: Study results showed that anastomotic leakage, surgical site infection, intra-abdominal collection, reoperation, and mortality rates were similar to the current literature obtained from the studies with mechanical bowel preparation. In addition, these results were found to be similar according to the resection site.