1464P - Impact of age on the benefit of immunotherapy for metastatic squamous cell lung cancer: An NCDB database analysis

Background

Immunotherapy represents an alternative to chemotherapy and clinical trial for squamous cell lung cancer. Due to the underrepresentation of elderly patients in clinical trials, it is not clear whether they derive similar benefit from immunotherapy as their younger patients.

Methods

A retrospective analysis using National Cancer Database (NCDB) was conducted in patients diagnosed with metastatic squamous cell lung carcinoma between 2016 and 2019. Kaplan Meier survival plots were used to examine survival outcome of different age groups: 19-49, 50-79 and 80 and older. Each age group was examined for benefit from chemotherapy (CR), chemotherapy + immunotherapy (CI), immunotherapy (IO), and no treatment (NR). Cox regression analysis was used to identify factors associated with overall survival.

Results

Of the 24,111 patients analyzed, 3,072 were 80 years or older. Patient who received immunotherapy had much better overall survival than those without. The one-year and two- years overall survival in these groups are CI: 52.98%, 18.10%; IO: 46.85%, 16.34%; CR: 40.11%, 10.73% and NR: 11.13%, 3.81% respectively. Although overall survival declined with age, age itself was not responsible for the poor outcome coming with it. No significant interaction effect was found between age and treatment. In multivariate analysis, HR was 1.01; 0.91-1.11; P=0.862 in age 19-49 and HR 1.02; 0.98-1.06, P=0.397 in age 50-79 compared to age 80 year or older (HR 1.0). Different age groups benefited similarly to all treatments. Compared to CR only (HR 1.0), treatment with CI conferred the best survival outcome HR 0.73; 95% CI 0.71-0.76; P<0.001; IO comes in next with HR 0.84 95% CI 0.80-0.88; P<0.001 and NR performed the worst (HR 2.90; 95% CI 2.80-3.0; P<0.001), suggesting that differences in survival is related to factors other than age.

Conclusions

Although immune senescence is of concern in senior patients receiving immunotherapy, older patients with squamous cell lung cancer benefit from treatment with immune therapy and chemotherapy combination, immunotherapy, chemotherapy as much as younger patients. Age itself is not associated with immunotherapy inefficacy.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Zhonglin Hao, MD.

Funding

In part by the NCI Cancer Center Support Grant P30 CA177558.

Disclosure

Z. Hao: Non-Financial Interests, Institutional, Local PI: Novartis Inc, BeiGene; Other, Personal, Advisory Role: Cardinal Health.