Background: The prognosis of patients with peritoneally metastasized colorectal cancer has improved significantly with the introduction of cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (CRS + HIPEC). Although a macroscopically complete resection is achieved in nearly every patient, recurrence rates are high. This study aims to identify risk factors for early recurrence, thereby offering ways to reduce its occurrence.
Methods: All patients with colorectal peritoneal carcinomatosis treated with CRS + HIPEC and a minimum follow-up of 12 months, in April 2014, were analyzed. Patient data were compared between patients with or without recurrence within 12 months after CRS + HIPEC. Risk factors were determined using logistic regression analysis. Postoperative complications were graded according to the serious adverse events (SAEs) score, with grade 3 or higher indicating complications requiring intervention.
Results: A complete macroscopic cytoreduction was achieved in 96 % of all patients treated with CRS + HIPEC. Forty-six of 133 patients (35 %) developed recurrence within 12 months. An SAE ≥3 after CRS + HIPEC was the only significant risk factor found for early recurrence (odds ratio 2.3; p = 0.046). Median survival in the early recurrence group was 19.3 months compared with 43.2 months in the group without early recurrence (p < 0.001). Patients with an SAE ≥3 showed a reduced survival compared with patients without such complications (22.1 vs. 31.0 months, respectively; p = 0.02).
Conclusions: Early recurrence after CRS + HIPEC is associated with a significant reduction in overall survival. This study identifies postoperative complications requiring intervention as the only significant risk factor for early recurrence, independent of the extent of peritoneal disease, highlighting the importance of minimizing the risk of postoperative complications.