The impact of the extent of surgery on late adverse effects following cytoreductive surgery and HIPEC

Aim: To investigate the impact of the surgical extent on late adverse effects (LAE) following cytoreductive surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC). Method: A prospective cohort study including patients undergoing CRS + HIPEC due to peritoneal metastases from gastrointestinal tumour origin. From 2006 through 2019, consecutive patients treated with CRS + HIPEC were followed at 3, 6 and 12 months, and LAEs were assessed using the symptom scales and items from the European Organization for Research and Treatment of Cancer QLQ-C30 (EORTC QLQ-C30). Surgical extent was categorized into three groups (major, intermediate, minor) based on peritonectomy procedures and colorectal resections performed as part of CRS. EORTC data were analysed using a linear mixed effects regression model adjusted for age, gender, origin of tumour and comorbidity. Results: In total, 257 patients who responded to at least one questionnaire during the follow-ups were included. Only diarrhoea symptoms were positively associated with surgical extent (mean differences: major vs. minor: 8.4 (-0.5; 17.2) (p = 0.06) and major vs. intermediate: 10.9 (3.8; 18.0) (p = 0.00)). Additionally, diarrhoea symptoms persisted throughout the study period and did not change over time (mean difference 12-3 months: -3.6 (-9.1; 1.7) (p-value = 0.18)). Overall, the levels of different symptom scales (fatigue, nausea and vomiting, pain, dyspnoea, and appetite loss) significantly decreased from 3 to 12 months. Conclusion: Patients undergoing extensive CRS suffer from persistent impaired gastrointestinal function in terms of diarrhoea compared patients undergoing to less extensive surgery. Attention should be directed at detecting such LAE and to guide patients accordingly.