Long-term survival after aggressive treatment of relapsed serosal or distant pseudomyxoma peritonei

Complete cytoreductive surgery (CCRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have dramatically changed the prognosis of patients with pseudomyxoma peritonei (PMP). However, recurrences can still occur and no consensus has been reached regarding their optimal treatments. This study aimed to analyze the patterns of recurrence after CCRS plus HIPEC for PMP and potential subsequent treatments of these lesions.

Between 1992 and 2014, patients who had relapsed after treatment of PMP were selected from a prospective database of 251 patients who had undergone CCRS plus HIPEC with a curative intent.

After a median follow-up of 85 months, 66 patients (26%) had relapsed with a median free interval of 25 months. The first recurrence was mostly located in the peritoneum, isolated in 50 patients (76%) and associated with extraperitoneal disease in 6 patients. Curatively intended treatment of the relapse, combining surgery and chemotherapy was achievable in 76% of the patients, leading to a 5-year overall survival (OS) rate of 83% from the date of treatment of the first recurrence. In contrast, the 5-year OS rate was only 27% (p < 0.001) for patients treated with non-curative therapy. An isolated peritoneal recurrence was predictive of greater amenability to curative therapy and a better prognosis.

After CCRS plus HIPEC, serosal recurrences were more common than their distant counterparts. Distant relapses' emergence has raised the question of their optimal treatments. Very long-term survival can be obtained after further treatment of recurrent PMP for patients with limited disease and good general status.