Alectinib hydrochlorideが奏効したanaplastic lymphoma kinase融合遺伝子陽性肺粘表皮癌

A Pulmonary Mucoepidermoid Carcinoma with Anaplastic Lymphoma Kinase Fusion Responding to Alectinib Hydrochloride

Anaplastic lymphoma kinase（ALK）融合遺伝子は肺腺癌の約5％程度にみられ，腺癌以外では陽性頻度はきわめて低いと報告されている．実際にALK融合遺伝子陽性の粘表皮癌はこれまでほとんど報告されていない．われわれはALK阻害薬alectinib hydrochlorideが奏効したALK融合遺伝子陽性肺癌の切除後再発例を経験したので報告する．

Few cases of lung mucoepidermoid carcinomas with anaplastic lymphoma kinase （ALK） fusion have been reported. A 35-year-old woman was found to have an abnormal chest X-ray. A tumor and obstructive pneumonitis in her left upper lobe was detected using computed tomography （CT）. She was admitted to our hospital, and was diagnosed with mucoepidermoid carcinoma by transbronchial biopsy. Left pneumonectomy and lymphadenectomy were performed for lung mucoepidermoid carcinoma and a mediastinal lymph node metastasis （pT2aN2M0, stage ⅢA）. Postoperative radiotherapy （50 Gy） to the mediastinum and chemotherapy were performed followed by several radiotherapies for cervical and mediastinal lymph node and right ischium metastases. Since then, further radiotherapy was impossible. However, we detected ALK fusion in the resected specimen and the cancer responded to alectinib hydrochloride.