Cytoreductive Surgery with Hyperthermic Intrathoracic Chemotherapy for Patients with Intrapleural Dissemination of Peritoneal Surface Malignancies.

BACKGROUND: Peritoneal surface malignancies (PSM) can disseminate into the pleural cavity, increasing morbidity and mortality. While cytoreductive surgery with hyperthermic intraperitoneal chemoperfusion (CRS/HIPEC) improves outcomes for PSM with intra-abdominal spread, the optimal approach for patients with pleural dissemination from PSM remains unclear. It seems reasonable to apply peritoneal carcinomatosis management principles to patients with pleural lesions using CRS and hyperthermic intrathoracic chemotherapy (HITHOC).

METHODS: We conducted a descriptive study to evaluate outcomes of PSM patients who underwent CRS/HITHOC for pleural dissemination using a high-volume PSM center's prospective database from October 1994-June 2020. CRS/HITHOC was performed via either diaphragmatic window during CRS/HIPEC (CRS/HIPEC+HITHOC) or thoracotomy as a separate procedure (CRS/HITHOC).

RESULTS: Of 852 completed CRS/HIPECs, 18 HITHOCs in 15 patients were identified: 10 CRS/HIPEC+HITHOCs, and 8 CRS/HITHOCs. CRS/HIPEC+HITHOC primary tumors included: 4 appendix, 4 ovary, 1 colon, and 1 unknown. All (n = 8) CRS/HITHOC patients had recurrent appendiceal neoplasms. Complete cytoreduction was achieved in 90% of CRS/HIPEC+HITHOCs and 75% of CRS/HITHOCs. Major complications occurred in 20% of CRS/HIPEC+HITHOCs and 13% of CRS/HITHOCs with no 30-day mortality in either group. After median follow-up of 22 months, overall survival at 1, 3, and 5 years was 93.3%, 67.9%, and 67.9%, while 1-, 3-, and 5-year progression-free survival was 70.9%, 20.3%, and 20.3%. Intrapleural recurrence occurred in 1 CRS/HIPEC+HITHOC and 2 CRS/HITHOC patients.

CONCLUSIONS: CRS/HITHOC performed via diaphragm or thoracotomy at high-volume centers is a safe option for PSM with pleural dissemination. Further comparative studies with longer follow-up are needed to evaluate survival by tumor type.