Total parietal peritonectomy leads to a low incidence of platinum resistance in patients undergoing interval cytoreductive surgery for advanced epithelial serous ovarian cancer- results of a prospective multi-centric study

Background and Aim Though interval cytoreductive surgery (CRS) following neoadjuvant chemotherapy (NACT) is considered non-inferior to primary CRS, the incidence of platinum resistance is high. A total parietal peritonectomy (TPP) can address occult microscopic disease more completely and could reduce the rates of early recurrence. The early results of a prospective study evaluating the role of TPP are presented in this manuscript. Methods This is a prospective, multi-centric interventional study. A TPP was performed in all patients undergoing interval CRS. A fixed surgical protocol was followed. Grade 3-4 morbidity was recorded. Factors affecting grade 3-4 morbidity, early recurrence and progression-free survival (PFS) were evaluated. Results From July 2018, 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%) patients; CC-1 in 10(14.2%). Grade 3-4 complications were seen in 15(21.4%) patients of which the commonest complication was intraperitoneal fluid collection. Occult disease in the peritoneum was seen in 40%. Early recurrence (platinum resistance) was seen in 5(7.1%). The median PFS was 18 months [range 0-21months]. Patients with a lower PCI and with no grade 3-4 complications had a significantly longer PFS. A pathological PCI>15 was the only independent predictor of a shorter PFS (p=0.001). Conclusions TPP performed as a part of interval CRS resulted in a very low incidence of platinum resistance. The post-operative morbidity was acceptable. These findings should be confirmed in a larger series and a randomized trial performed to demonstrate demonstrate its benefit over conventional surgery.