Clinical application of trastuzumab plus chemotherapy in the treatment of HER2-positive gastric or gastro-oesophageal junction adenocarcinoma: a retrospective analysis of 75 cases

Objective To evaluate the effcacy and safety of trastuzumab combined with chemotherapy for the treatment of human epidermal growth factor 2 (HER2)-positive chemo-refractory gastric or gastro-oesophageal junction adenocarcinoma in China. Methods The clinical data of seventy-five cases of HER2-positive and chemo-refractory gastric or gastro-oesophageal junction adenocarcinoma were collected in Peking University Cancer Hospital from May 2006 to Nov. 2013. Patients with historically confirmed adenocarcinoma were eligible if their tumors showed overexpression of HER2 protein by immunohistochemistry  or ISH positive, and if they were treated with trastuzumab combined with chemotherapy. Response and toxicity were evaluated with RECIST 1.0 and CTC AE 3.0 criteria. Results All the 75 patients received trastuzumab plus chemotherapy. In 52 patients of first line therapy, combination regimens consisted of 44 cisplatin or oxaliplatin with fluorouracil (as adjuvant therapy in 3 patients with prolonged follow up), 5 with paclitaxel with fluorouracil, and 3 with gimeracil and oteracil potassium monotherapy. Evaluation of curative effects was performed in 49 cases, in whom 32 with PR (61.5%), 13 with SD, and 4 with PD. The disease control rate (DCR) was 86.5%. Median PFS and median OS were 10.9 months (95%CI 6.8-15.0) and 18.7 months (95%CI 6.3-31.1) respectively. Three patients received radical operation followed by oxaliplatin + capecitabine. In 20 cases with second-line or delayed therapy, combination cisplatin or oxaliplatin with fluorouracil were given in 9 patients, paclitaxel with fluorouracil in 5, fluorouracil monotherapy in 3, irinotecan monotherapy in 2, and docetaxel monotherapy in 1 patient. In 20 cases, PR (35.0%) was achieved in 7, SD was achieved in 6, and PD was achieved in 7. The DCR was 65%. Median PFS and median OS were 6.2 months (95%CI 5.1-7.3) and 12.3 months (95%CI 9.0-15.6) respectively. The median time of Trastuzumab administration was 7. Adverse events (3/4 grade) were neutropenia (14.7%) and thrombocytopenia (10.7%). Allergy and fever was reported in one each patient respcetively. Conclusion Trastuzumab plus chemotherapy have been proved to be effective in real clinical practice in China, and it is well tolerated and effective in patients with HER2-positive gastric or gastro-oesophageal junction adenocarninoma. Prospective studies are warranted to further confirm its effcacy and safety as a maintenance therapy or second line therapy. DOI: 10.11855/j.issn.0577-7402.2014.03.08