B37 - Trastuzumab plus chemotherapy in the treatment of HER-2 –positive, advanced, gastric or gastro-esophageal junction cancer: a single center experience

Abstract

Background: Recent genomic studies have identified potentially targetable genomic alterations in gastric and gastro-esophageal cancer. HER-2, the human epidermal growth factor receptor type2, amplificated or overexpressed in the 7-34% of advanced gastric and gastro-esophageal cancer, is actually the only biomarker-driven therapy in clinical practice. The Toga study assessed the treatment with chemotherapy plus trastzumab, a monoclan antibody against HER-2,as the new standard of care for patients with HER2-positive advanced gastric or gastro-esophageal junction cancer. Patients and methods: We retrospectively assessed pts with histologically confirmed diagnosis of inoperable locally advanced or metastatic gastric and gastro-esophageal adenocarcinoma, with high expression of HER2,immunohistochemistry 2+ and SISH positive or immunoistochemistry 3 +, treated with trastuzumab plus chemotherapy(5-FU or capecitabine and CDDP) at our Institution, from October 2012 to November 2015. Clinical, radiological and laboratory data were available on electronic medical records of our Hospital. The OS and the PFS in our experience were analysed using Kaplan Meier method in the trastuzumab plus chemotherapy group. Results: We collected data from 13 pts, 3 female and 10 male, median age 65 (range 46-82). The site of primitive tumor was gastro-esophageal junction in 61% of pts and stomach in 39% of pts. 9 pts with metastatic disease and 4 pts with locally advanced disease. The median number of cycles of trastuzumab therapy was 7 (range 1-23). Second line therapy after disease progression was given to 3/13 pts. The most common adverse event were fatigue, gastro-intestinal and haematological toxicity. Cardiac adverse event weren't reported. The OS and PFS were respectively 16 months and 9 months, better then the 13,8 months OS and 6,7 months PFS reported in the Toga Study. Conclusions: Despite a short median follow-up period and a small group of pts, in our experience, the combination of chemotherapy plus trastuzumab for pts with HER2+ advanced gastric and gastro-esophageal junction cancer showed a clinical improvement in terms of OS and PFS and confirmed in the real world the expectation generated by the Toga trial.