Neoadjuvant Alectinib in a Patient With Anaplastic Lymphoma Kinase (ALK)-Mutant Stage III Lung Adenocarcinoma: A Case Report.

Lung adenocarcinoma is a heterogeneous malignancy requiring personalized therapeutic strategies. This case report details the management of a 33-year-old male never-smoker diagnosed with stage III lung adenocarcinoma harboring an Echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) fusion gene. Traditional chemoimmunotherapy has shown modest efficacy for this aggressive cancer subtype. The patient presented with a large left upper lobe lung mass and mediastinal lymphadenopathy. Molecular testing revealed an EML4-ALK rearrangement and high programmed cell death-ligand 1 (PD-L1) expression. Initial treatment with chemoimmunotherapy was complicated by hypersensitivity reactions to nivolumab and paclitaxel, leading to a brief hospitalization. The treatment strategy was shifted to neoadjuvant alectinib, 600 mg twice daily. The patient tolerated the therapy well, experiencing only a transient photosensitivity rash. Subsequent imaging showed significant tumor reduction and no disease progression. In April 2024, the patient underwent successful surgical resection, revealing a complete pathological response with no residual tumor. This case demonstrates the efficacy of neoadjuvant alectinib in managing ALK-mutant stage III lung adenocarcinoma, highlighting the potential benefits of targeted therapy in the neoadjuvant setting. Further studies are needed to establish optimal treatment protocols for patients with ALK-positive lung cancer.