Quality of Life and Functional Outcomes After Rectal Cancer Surgery: A Comparative Study Applying EORTC QLQ-C30, QLQ-CR29, and LARS Score at 1–6 Months Postoperatively

Background/Objectives: Quality of life (QoL) and functional recovery are essential outcomes in patients undergoing rectal cancer surgery. In addition to oncological results, bowel dysfunction and stoma-related issues may significantly affect postoperative well-being. We aimed to evaluate QoL changes at 1 and 6 months postoperatively and functional outcomes in rectal cancer patients who underwent curative surgical treatment, sphincter-preserving surgeries (SPS) or abdominoperineal resection (APR). Owing to its impact on QoL, several functions were assessed using the Low Anterior Resection Syndrome (LARS) score. Methods: This retrospective observational study consisted of 99 patients who underwent curative rectal cancer surgery, of which 38 patients had colostomy, and 61 no colostomy. To assess patient-reported outcomes related to QoL, the EORTC QLQ-C30 questionnaire, QLQ-CR29 questionnaire, and LARS instrument were sent to the patients at 1 and 6 months postoperatively. Changes over time were analyzed using paired statistical tests, and subgroup analyses were performed according to colostomy status and surgical approach. Results: Significant improvements were observed in the global health status and all major functional domains between 1 and 6 months postoperatively. The global health status increased from 74.9% to 86.5% (p < 0.001). Symptom burden decreased significantly, particularly for fatigue (−18.31), pain (−14.48), diarrhea (−12.46), and insomnia (−11.45), representing clinically meaningful improvements. Patients who underwent abdominoperineal resection or resection with colostomy had lower QoL scores at 1 month but showed substantial improvement at 6 months, becoming comparable to those who underwent SPS. LARS outcomes demonstrated progressive functional recovery, with the proportion of patients without LARS increasing from 39 to 46, while major LARS decreased from 7 to 3 patients. However, approximately 40% of patients in the SPS group continued to report moderate-to-severe LARS symptoms. Conclusions: In this study, QoL and bowel function improved significantly during the first 6 months after colorectal cancer surgery. Although most patients demonstrated recovery, persistent bowel dysfunction and stoma-related challenges remain important issues. These findings highlight the need for comprehensive postoperative care and routine assessment of both QoL and functional outcomes.