PROGNOSTIC FEATURES OF 51 COLORECTAL AND 130 APPENDICEAL CANCER-PATIENTS WITH PERITONEAL CARCINOMATOSIS TREATED BY CYTOREDUCTIVE SURGERY AND INTRAPERITONEAL CHEMOTHERAPY

Objective A treatment plan to be used in patients with peritoneal carcinomatosis was devised and tested as a Phase II study. Background Peritoneal carcinomatosis from appendical or colorectal cancer has been regarded as a fatal clinical entity. Treatment protocols have not been reported previously. Methods The authors used cytoreductive surgery and intraperitoneal chemotherapy to treat 181 consecutive patients with peritoneal carcinomatosis. There were 51 patients with colorectal cancer and 130 patients with appendiceal cancer. Mean followup is 24 months, with a range of 0 to 149 months. Results Clinical features that showed prognostic significance included appendiceal versus colorectal primary tumors (p = 0.0001), grade 1 versus grades 2 and 3 histopathology (p = 0.0003), complete versus incomplete cytoreductions (p = 0.0001), lymph node-negative verses lymph node-positive primary tumors (p = 0.0001), and volume of peritoneal carcinomatosis present preoperatively for colon cancer (p = 0.0006). Features with no statistical prognostic significance included preoperative tumor volume for appendiceal cancer, age, sex, number of cycles of chemotherapy, operative time, complications, blood loss, and institution providing treatment. From these prognostic features, four prognostic groups were identified, and 3-year survival was estimated by the product-limit survival method. Group I patients (n = 76) were those with grade 1 histology, no lymph node metastases, and complete cytoreductions (survival at 3 years = 99%). Group II patients (n = 23) were those with grade 2 or 3 histology, no lymph node metastases, and complete cytoreductions (65%). Group III patients (n = 24) had any histology, lymph node metastases, and complete cytoreductions (66%). Group IV patients (n = 58) had incomplete cytoreductions (20%). Conclusions Peritoneal carcinomatosis is a treatable condition in selected patients with the possibility for longterm, disease-free survival.