A patient with ALK‐positive lung adenocarcinoma who survived alectinib‐refractory postoperative recurrence for 4 years by switching to ceritinib

Echinoderm microtubule‐associated protein‐like 4‐anaplastic lymphoma kinase (EML4‐ALK) rearrangements are found in ~ 5% of patients with non‐small cell lung cancer (NSCLC). Several tyrosine kinase inhibitors (TKIs) have been developed for treatment of so‐called ALK‐positive NSCLC. In cases of tumor progression during treatment with second‐generation ALK‐TKIs, such as alectinib, brigatinib, or ceritinib, National Comprehensive Cancer Network guidelines propose a switch to lorlatinib, a third‐generation ALK‐TKI, or to cytotoxic chemotherapy. However, they do not mention switching to other second‐generation ALK‐TKIs. Here, we present a rare case of a 53‐year‐old Japanese woman, who had never smoked, with ALK‐positive lung adenocarcinoma who survived alectinib‐resistant postoperative recurrence for 4 years by switching to ceritinib. She underwent curative resection for lung adenocarcinoma, but the cancer recurred at the bronchial stump and mediastinal lymph nodes. After platinum‐doublet chemotherapy, the patient still had a single growing liver metastasis, but the tumor was found to harbor EML4‐ALK rearrangement. Therefore, the patient started to take ALK‐TKIs. Alectinib was the second ALK‐TKI used to treat this patient. Alectinib shrank the liver metastasis, which was surgically resected. The tumor relapsed again during continued treatment with alectinib, which was switched to ceritinib. Ceritinib was effective for the relapsed tumor and treatment continued well for 4 years. This case report suggests that, in case of tumor progression during treatment with a second‐generation ALK‐TKI, switching to another second‐generation ALK‐TKI may be one of the treatment options. Further analyses are warranted to find robust markers to determine which ALK‐TKI is best for each patient.