Background: Cytoreductive surgery (CRS) provides a survival benefit when achieved without residual disease. As diaphragm is frequently affected in peritoneal malignancies, complete cytoreduction often requires surgical techniques over the diaphragm. The purpose of the study was to assess diaphragmatic resection impact on cytoreduction completeness, morbidity and mortality compared to less aggressive diaphragmatic peritonectomy in CRS and hyperthermic intraperitoneal chemotherapy (HIPEC) settings.
Materials and methods: Patients with peritoneal carcinomatosis and supramesocolic disease undergoing CRS/HIPEC from 2011 to 2019 were included in a prospectively collected database. We compared patients who underwent full-thickness diaphragmatic resection (DR) and diaphragmatic peritonectomy (DP). Epidemiological and clinical data, morbidity, and mortality within 90 days of surgery were documented.
Results: 232 patients were initially selected. Inclusion criteria were met by 88 procedures. DR was performed on 32 patients and DP on 56. Number of resected organs was 5.21 in the DR cohort vs. 3.57 in the DP cohort (p<0.0001). Rate of Peritoneal Cancer Index (PCI) score >14 was higher in the DR group (75%) than in the DP group (50.9%) (p=0.027). Tumor invasion of diaphragmatic muscle after DR was confirmed in 89.3% patients. Postoperative pleural effusion was observed in 28 patients (50%) in the DP group and in 17 (53.1%) in the DR group.
Conclusions: CRS/HIPEC requires specific surgical techniques over the diaphragm to achieve complete cytoreduction. As diaphragmatic muscle invasion is frequent, full-thickness resection may allow a cytoreduction completeness increase without an increased morbidity. Pleural drains are not systematically required as these procedures show low incidence of major respiratory complications.