Case report: Personalized, response-adapted neoadjuvant alectinib achieves durable remission in stage IIIB ALK-rearranged lung cancer.

Background: Alectinib, a second-generation ALK inhibitor, is established as a first-line treatment for advanced ALK-positive NSCLC and as adjuvant therapy following resection for early-stage disease. However, its role as a neoadjuvant therapy remains under investigation. Case presentation: We report a 57-year-old never-smoking woman diagnosed with stage IIIB (cT4N2M0) ALK-rearranged lung adenocarcinoma. After the initial multidisciplinary team (MDT) convening, a consensus was reached to initiate neoadjuvant alectinib (600 mg twice daily), with the first response evaluation scheduled at 4 weeks. The first restaging computed tomography (CT) demonstrated a significant partial response (PR), characterized by a 76% reduction in the primary tumor diameter and a 50% reduction in the short axis of the station 7 lymph node. In light of this robust response which already met surgical criteria, the MDT decided to proceed with a second 4-week consolidation cycle to maximize the pathological response prior to surgery. Following the second cycle, subsequent imaging confirmed further tumor regression. The patient then underwent successful R0 resection, with pathology confirming a major pathological response (MPR). Adjuvant alectinib was resumed on postoperative day 2. At the last follow-up (33 months post-surgery), the patient remains disease-free with no clinically significant treatment-related adverse events. Conclusion: This case illustrates the successful personalization of neoadjuvant alectinib by employing an imaging response-adapted strategy. This strategy utilized dynamic imaging assessments to guide the scheduling of the surgical procedure, culminating in a deep pathological response and prolonged disease-free survival, thereby offering a refined perioperative paradigm for ALK-rearranged NSCLC.