Objectives: Bowel dysfunction is frequently reported in patients with gynecologic cancers and could be validly estimated after large bowel resection by low anterior resection syndrome (LARS) scoring. We aimed to evaluate the prevalence of LARS-like symptoms in primary diagnosed ovarian cancer (OC) and the effect of surgery regarding recto-sigmoid resection. Methods: A prospective longitudinal observational cohort study was performed, including patients with newly diagnosed epithelial OC treated by primary or interval surgery with a residual tumor less than 1 cm between 2019 and 2021. Cases with stoma were excluded. Intestinal dysfunction was assessed through a known LARS score questionnaire regarding flatus and/or feces incontinence and urgent and frequent bowel peristalsis, answered pre and postoperatively. Based on the scoring, the patient was classified into three subgroups: no (0-20), minor (21-29), and major LARS (30-42). In addition, their subjective bother and impact on quality of life (QOL) were evaluated by a single question, which gave an impression of the impact on the patient’s daily life (answer options: no or minimal [minor], and moderate or severe [major]). Results: In total, 84 patients answered the score questionnaire before and after surgery; the meantime interval was 374 days. LARS-like symptoms were reported preoperatively in 35.7% (n=30): 25% minor and 10.7% major; and postoperatively in 47.6% (n=40), of them, 26.2% were minor and 21.4% major. Pre and postoperative major LARS-like symptoms were predominantly reported in patients with stage FIGO III-IV (100% and 94.4%, respectively). Recto-sigmoid resection was performed in 52.4% (n=44) with primary end-to-end anastomosis. Major LARS and major negative impact on QOL after recto-sigmoid resection were observed in 27.3% and 40.5%, respectively. In multivariate analysis, preoperative LARS-like symptoms, regardless of the severity, demonstrated the unique significant independent risk factor for postoperative major LARS (preoperative minor: HR: 6.16; 95% CI: 1.66-22.86, p=0.007; preoperative major: HR: 9.01; 95% CI: 1.74-46.79, p=0.009). Conclusions: LARS-like symptoms appear in one-third of ovarian cancer patients preoperatively and could help identify a high-risk group for such symptoms postoperatively. Major LARS and negative impact on QOL show a linear correlation and seem to be diagnosed frequently after recto-sigmoid resection during debulking operation. Objectives: Bowel dysfunction is frequently reported in patients with gynecologic cancers and could be validly estimated after large bowel resection by low anterior resection syndrome (LARS) scoring. We aimed to evaluate the prevalence of LARS-like symptoms in primary diagnosed ovarian cancer (OC) and the effect of surgery regarding recto-sigmoid resection. Methods: A prospective longitudinal observational cohort study was performed, including patients with newly diagnosed epithelial OC treated by primary or interval surgery with a residual tumor less than 1 cm between 2019 and 2021. Cases with stoma were excluded. Intestinal dysfunction was assessed through a known LARS score questionnaire regarding flatus and/or feces incontinence and urgent and frequent bowel peristalsis, answered pre and postoperatively. Based on the scoring, the patient was classified into three subgroups: no (0-20), minor (21-29), and major LARS (30-42). In addition, their subjective bother and impact on quality of life (QOL) were evaluated by a single question, which gave an impression of the impact on the patient’s daily life (answer options: no or minimal [minor], and moderate or severe [major]). Results: In total, 84 patients answered the score questionnaire before and after surgery; the meantime interval was 374 days. LARS-like symptoms were reported preoperatively in 35.7% (n=30): 25% minor and 10.7% major; and postoperatively in 47.6% (n=40), of them, 26.2% were minor and 21.4% major. Pre and postoperative major LARS-like symptoms were predominantly reported in patients with stage FIGO III-IV (100% and 94.4%, respectively). Recto-sigmoid resection was performed in 52.4% (n=44) with primary end-to-end anastomosis. Major LARS and major negative impact on QOL after recto-sigmoid resection were observed in 27.3% and 40.5%, respectively. In multivariate analysis, preoperative LARS-like symptoms, regardless of the severity, demonstrated the unique significant independent risk factor for postoperative major LARS (preoperative minor: HR: 6.16; 95% CI: 1.66-22.86, p=0.007; preoperative major: HR: 9.01; 95% CI: 1.74-46.79, p=0.009). Conclusions: LARS-like symptoms appear in one-third of ovarian cancer patients preoperatively and could help identify a high-risk group for such symptoms postoperatively. Major LARS and negative impact on QOL show a linear correlation and seem to be diagnosed frequently after recto-sigmoid resection during debulking operation.