BACKGROUND: Although ALK-translocated (ALK+) advanced non-small cell lung cancers (aNSCLCs) are currently treated with second- or third-generation ALK inhibitors (ALK-TKIs), some patients respond durably to the first-generation ALK-TKI crizotinib.
OBJECTIVE: This study aimed to describe the clinical characteristics of these long-term responders.
PATIENTS AND METHODS: This national, multicenter, retrospective, non-interventional study included patients with ALK+ aNSCLCs and long-term responses to first (L1)- or subsequent (≥ L2)-line crizotinib, defined, respectively, as treatments lasting > 18 and > 10 months. Median treatment duration (mDOT) was the primary endpoint.
RESULTS: A total of 85 patients (32 L1 and 53 ≥ L2 responders) from 23 centers were included (receiving crizotinib between 10/24/2011-10/02/2018): median age of 59 years, 83.6% non-smokers or ex-smokers, 85.9% performance status (PS) 0/1, 94.1% with adenocarcinomas, median of one metastatic site, and 22.4% with brain metastases (BMs). After median follow-up of 73.4 [95% confidence interval, 67.5-79.9] months, respective L1 and ≥ L2 mDOTs were 43.3 [26.7-56.8] and 29.6 [22.6-35.8] months, with overall survival (OS) not reached (NR) and 116.2 [83.4-NR] months. BM presence or absence did not affect mDOT (31.4 versus 32.9 months) but significantly impacted median OS (70.6 versus 158.6 months; p = 0.0008). Progression on crizotinib was paucisymptomatic (74.1%) and oligometastatic (34.8%), especially BMs (42.4%). After crizotinib discontinuation, 65 (76.5%) patients received subsequent systemic therapy: 57 (67.1%) with second-generation ALK-TKIs. Respective mDOTs of first- and second-line post-crizotinib ALK-TKIs lasted 19.4 [14.9-25.6] and 11.1 [4.8-17.9] months, respectively.
CONCLUSIONS: Most ALK+ aNSCLC patients with prolonged crizotinib efficacy had paucisymptomatic and oligometastatic disease without BMs. They subsequently benefited from a sequential strategy with other ALK-TKIs.