Feasibility of intraperitoneal Trastuzumab treatment in a patient with peritoneal carcinomatosis from gastric cancer

OBJECTIVES: This case report evaluates the feasibility and efficacy of intraperitoneal (IP) trastuzumab administration in gastric cancer (GC) patients with peritoneal carcinomatoses. METHODS: Peritoneal metastasis is a common sign of advanced tumor stage, tumor progression or disease recurrence in patients with GC. Recently, the role of HER2 overexpression in GC, occurring in about 20% of cases, is correlated with a worse prognosis.We report the case of 61-years old female, admitted to our Hospital after curative surgery for GC with over-expression of HER2. Seven months after the start of first line chemotherapy treatment a pleuro-peritoneal disease progression occurred, documented by cytological exam; according to HER2 status, we decided to treat the patient with IP trastuzumab administration. RESULTS: Between September and October 2012, the patient (ECOG performance status was 0), underwent to 6 cycles of IP trastuzumab. Trastuzumab was administered weekly at a dose of 150 mg for each cycle after paracentesis. The safety was good, no local complications (e.g. abdominal pain, peritonitis) occurred. The clinical revaluation evidenced a stable peritoneal disease. CONCLUSIONS: To our knowledge this is the first report on Trastuzumab use to treat IP metastases from GC, with acceptable toxicity and local disease control.