Prolonged survival with alectinib in a patient with advanced lung adenocarcinoma: a case report and literature review.

[BACKGROUND] Alectinib is a second-generation tyrosine kinase inhibitor (TKI) that selectively targets anaplastic lymphoma kinase () rearrangements and is recommended as first-line therapy for patients with advanced -positive non-small cell lung cancer (NSCLC). Pivotal clinical trials have demonstrated its superior efficacy and favorable safety profile compared with earlier inhibitors and chemotherapy. However, long-term real-world outcomes remain insufficiently characterized, particularly in patients harboring concurrent alterations and additional rare genetic variants, whose clinical relevance is often unclear.

[CASE DESCRIPTION] We report a case of a 41-year-old female diagnosed with stage IV lung adenocarcinoma (LUAD) following routine imaging. Comprehensive diagnostic evaluation, including positron emission tomography/computed tomography (PET-CT), cervical lymph node biopsy, and targeted next-generation sequencing, revealed an - fusion (variant 1) together with a concurrent mutation. The patient initiated first-line treatment with alectinib at a daily dose of 1,200 mg. A partial response was achieved within two months of therapy, and disease control was sustained throughout long-term follow-up. Remarkably, after more than 62 months of continuous alectinib treatment, the patient remained progression-free, with no evidence of disease relapse, distant metastasis, or treatment-related adverse events. The identified alteration is currently classified as a variant of uncertain significance, and its functional or clinical impact has not been established.

[CONCLUSIONS] This case demonstrates an exceptionally durable response to first-line alectinib in an -positive LUAD patient with a concurrent rare variant. It underscores the long-term efficacy and tolerability of alectinib and highlights the importance of comprehensive genomic profiling in guiding personalized targeted therapy for genetically complex NSCLC.