Safety and efficacy of bidirectional chemotherapy for treatment of patients with peritoneal dissemination from gastric cancer: Selection for cytoreductive surgery

There is no standard treatment for peritoneal carcinomatosis (PC) from gastric cancer. New bidirectional chemotherapy (neoadjuvant intraperitoneal‐systemic chemotherapy protocol (NIPS)) was developed. The aim of the present study was to assess the safety and efficacy of NIPS and to show the selection for cytoreductive surgery on PC from gastric cancer. Seventy‐nine patients with PC from gastric cancer were treated with NIPS. A peritoneal port system was introduced into the abdominal cavity. The peritoneal wash cytological examination through a port was done before and after NIPS. The patients were treated with oral TS‐1 twice a daily for 21 days, followed by a 1‐week rest. On day 1, 8, and 15 from the start of oral TS‐1 administration, 30 mg/m2 of Docetaxel and 30 mg/m2 of cisplatinum with 500 ml of saline were introduced into the peritoneal cavity through the port. A median course of oral TS‐1 was 2.1 course and a median time of IP chemoterapy was 5.8. Peritoneal free cancer cells (PFCCs) had been detected in 65 (82.2%) patients before NIPS, and the positive cytology changed to be negative in 41 (63.0%) patients after NIPS. After NIPS, 41 patients underwent laparotomy, and complete cytoreduction was done in 32 (78%) patients. Complete cytoreduction was done in 27 (51.9%) of 52 patients with negative cytology but in only 4 (14.8%) of 27 patients with positive cytology (P