Peritoneal Disease Severity Score Predicts the Prognosis of Peritoneal Metastasis of Colorectal Origin: A 10-year Longitudinal Analysis of a Single-center Experience

Aim:Peritoneal Surface Disease Severity score (PSDSS) has been used in the evaluation of patients who are scheduled for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal metastasis of colorectal origin (PMCO). The aim of this study was to evaluate the validity of PSDSS in predicting prognosis in patients who underwent CRS + HIPEC for PMCO at our center.Method:Demographic data, operation data, histopathological features, perioperative morbidity and mortality, and oncologic follow-up data were obtained retrospectively from the database and analyzed. Peritoneal carcinomatosis index (PCI) values were calculated from preoperative computed tomographies. PSDSS was calculated by evaluating clinical symptoms, PCI and histology of primary tumor. Two PSDSS groups were formed: PSDSS 1 and 2 groups as low PSDSS group, and PSDSS 3 and 4 groups as high PSDSS group.Results:Sixty-one patients, including 36 females (59%) and 25 males (41%), with PMCO who underwent CRS and HIPEC were included in the study. Forty-four patients were enrolled to the low PSDSS group and 17 patients were enrolled to the high PSDSS group. Three patients (3.2%) died during the perioperative period. Twenty-one patients (34.4%) had perioperative complications. The mean follow-up was 35.0±23.2 months. During the follow-up period, 36 patients (59%) had recurrence and 44 patients (72.1%) died. The mean survival was 46.5±5.5 months, and 1-,3- and 5-year survival rates were 85%, 47% and 21%, respectively. There was no correlation between low and high PSDSS groups in terms of morbidity and recurrence (p=0.486 and p=0.385, respectively). Mortality was more frequent in high PSDSS group (94% vs. 63%; p=0.024). The mean survival of patients in the low PSDSS group was significantly longer than in the high PSDSS group (57.2±6.7 months vs. 16.5±2.6 months; p=0.001).Conclusion:The findings of this study demonstrated the validity of PSDSS in predicting prognosis in patients with PMCO who were scheduled for CRS and HIPEC