트라스투주맙 치료에 반응을 보인 HER2/neu 양성 전이성 타액관 암종 1예

Trastuzumab in a Patient with Metastatic Salivary Duct Carcinoma : A Case Report

Salivary duct carcinoma(SDC) is rare malignancy, accounting for approximately 1-3% of all malignant sali-vary gland tumors. Systemic chemotherapy has been used for stage IV SDC, but there is no consensus on the stan-dard treatment. SDC is histologically similar to ductal carcinoma of breast and often overexpress HER2/neu, hence HER2/neu targeted therapy could be one of treatment options. A 75-year-old Arabian man was diagnosed as SDC of right parotid gland with extensive metastases. He received oral 5-FU as palliative chemotherapy, but he was intolerable to oral chemotherapy due to severe oral mucositis. Considering immunohistochemical stain of tu-mor tissue showing strong positive for HER2/neu, we decided to administer an anti-HER2/neu antibody, trastu-zumab. Follow-up CT scans before the third dose of trastuzumab demonstrated remarkable regression of multiple metastases as well as primary tumor. This case suggests that HER2/neu targeted therapy may be a potential thera-peutic option for the SDC patient with overexpression of HER2/neu.