Targeted therapy in lung cancer: Are we closing the gap in years of life lost?

PURPOSE

Patients with non-small cell lung cancer (NSCLC) that harbor driver mutations are associated with a cancer diagnosis at a younger age. While targeted therapies provide deep remissions and durable benefit in a subset of patients, it is unclear whether targeted therapies bridge the gap in years of life lost (YLL) in these younger NSCLC patients with targetable mutations in comparison to generally older NSCLC patients without actionable driver mutations.

MATERIALS AND METHODS

Retrospective cross-sectional study using landmark trials leading to the approval of targeted therapies in NSCLC with actionable mutations. We evaluated all targeted therapies as well as chemotherapy and IO regimens for the treatment of NSCLC through FDA Oncology Announcements and NCCN Guidelines for NSCLC (version 4.2021).

RESULTS

We estimated the YLL for each driver mutation, cumulative median duration of response (DOR) with targeted therapies by mutation type, and percentage of estimated improvement in YLL from NSCLC targeted therapies. The median ages at diagnosis (in years) for patients whose tumors express targetable mutations were: 47.6 (NTRK); 52.0 (ALK); 62.0 (HER2); 57.0 (ROS1); 61.4 (RET); 63.0 (BRAF); 69.0 (EGFR); and 72.0 (MET). For comparison, the median age at diagnosis for patients without driver mutations, regardless of PD-L1 status was 71 years. The median DOR (in years) for patients whose tumors express the same mutations include: 0.9 (NTRK); 3.9 (ALK); 0.6 (HER2); 6.2 (ROS1); 2.2 (RET); 1.5 (BRAF); 3.1 (EGFR); and 2.4 (MET). The median DOR for patients without driver mutations was 1.2 years. The cumulative estimated survival time (years; median age at diagnosis plus the median DOR or OS) for patients whose tumors express targetable mutations were: 48.5 (NTRK); 55.9 (ALK); 62.6 (HER2); 63.2 (ROS1); 63.6 (RET); 64.5 (BRAF); 72.1 (EGFR); and 74.4 (MET). The cumulative estimated survival time for patients without driver mutations, regardless of PD-L1 status, was 72.2 years of age. We calculated the number of years NSCLC is diagnosed earlier in patients with targetable mutations as follows: 23.4 (NTRK), 19 (ALK), 14 (ROS1), 11 (EGFR), 9.6 (RET), 9 (HER2), and 8 (BRAF). The percent difference (%) ameliorated in YLL by mutation type is as follows: 44.3 (ROS1), 28.2 (EGFR), 22.9 (RET), 20.5 (ALK), 18.8 (BRAF), 6.4 (HER2), and 3.7 (NTRK).

CONCLUSION

Although targeted therapies have paved the way for significant progress toward providing a survival benefit to many young patients with advanced NSCLC with actionable mutations, it is evident that these therapies still leave a wide gap in the YLL in these younger patients compared to generally older individuals with advanced NSCLC without targetable mutations.