Total parietal peritonectomy performed during interval cytoreductive surgery for advanced epithelial serous ovarian cancer results in a low incidence of platinum resistant recurrence- results of a prospective multi-centre study.

BACKGROUND: The reported incidence of platinum resistant recurrence (PRR) (recurrence within 6 months of the last dose of platinum therapy) after interval debulking/cytoreductive surgery (CRS) is high compared to that after primary CRS. The goal was to study PRR following a total parietal peritonectomy (TPP), that addresses occult disease more completely.

METHODS: This is a prospective multi-center study (CTRI/2018/08/015350). A TPP was performed during interval CRS following a fixed surgical protocol. Patients with a follow-up of 6 months(M) or more were included in this analysis. The incidence and patterns of PRR and factors affecting recurrence were analyzed.

RESULTS: From July 2018 to October 2019, 70 patients with serous carcinoma were included. The median surgical PCI was 15 [range 5-37]. A CC-0 resection was obtained in 55 (78.5%); CC-1 in 10 (14.2%). Occult residual disease was seen in 40%. At a median follow-up of 13 months, 17 (24.2%) had developed recurrence/progression. PRR was seen in 5 (7.1%) patients. The sites of progression (>1 in 2 patients) were pleura (n = 1), visceral peritoneum (n = 2), retroperitoneal nodes (n = 2), mediastinal nodes (n = 1) and small bowel mesentery (n = 2). Overall, though the most common site of recurrence was the visceral peritoneum (N = 9), seven (>40%) patients did not develop recurrence in the visceral peritoneum. Patients with high PCI and grade 3-4 complications had a higher probability of developing recurrence.

CONCLUSIONS: TPP performed during interval CRS resulted in a very low incidence of PRR. These findings need confirmation in a larger series. The benefit of TPP over conventional surgery should be evaluated in a randomized trial.