Abstract
Background. ALK fusion gene-positive (ALK-positive) non-small-cell lung cancer (NSCLC) occasionally develops tolerance for ALK tyrosine kinase inhibitor (ALK-TKI). It is known that leptomeningeal carcinomatosis is difficult to treat and fatal. We herein report a case of ALK-positive NSCLC presenting with leptomeningeal carcinomatosis that was successfully treated with alectinib after gaining crizotinib resistance. Case. A 45-year-old female patient who had been diagnosed with ALK-positive lung adenocarcinoma (cT3N2M1b, OSS, stage IV) was treated with a combination of carboplatin, pemetrexed, and bevacizumab, followed by maintenance therapy with pemetrexed and bevacizumab, which resulted in a partial response. After her disease progressed, a partial response was obtained with crizotinib. However, leptomeningeal carcinomatosis occurred. We changed to alectinib, and a dramatic response was observed in the leptomeningeal carcinomatosis; however, the patient's liver metastasis worsened two months later. The patient's liver metastasis and primary lesion gradually progressed without the worsening of leptomeningeal carcinomatosis, despite various treatments. She eventually died due to Trousseau syndrome. Conclusion. In ALK-positive lung cancers presenting with leptomeningeal carciomatosis, alectinib should be the preferred agent. The continued use of alectinib beyond progressive disease (PD) may be useful even when PD is observed at the other target lesions.
