A national study of lung cancer patients below 50 years: Variations in characteristics and outcomes by age

Lung cancer predominantly affects the elderly. However, a small yet significant subgroup of patients below fifty years presents unique challenges in diagnosis and treatment. This study aims to describe the characteristics and outcomes of these young patients, emphasizing the need for improved diagnostic strategies and better prognostic outcomes.

This national cohort study includes all patients diagnosed 2012-2023 recorded in the Danish Lung Cancer Registry. Patients below fifty years at diagnosis were categorized as young.

Out of 57,325 patients a total of 1312 (2.3 %) were below fifty years at diagnosis. Young patients were more likely to be female (p = 0.006), diagnosed with adenocarcinoma (p < 0.001) and ten times more frequent anaplastic lymphoma kinase (ALK) mutated (p < 0.001). Young patients had fewer packyears (p < 0.001), better performance status (p < 0.001), lower Charlson Comorbidity index (p < 0.001), but were more frequently diagnosed in incurable disease stage, (68.0 % vs. 60.9 % p < 0.001). Adjusted OR of being diagnosed in a curable stage was 0.75 (95 %CI 0.66-0.85) for young patients, while adjusted OR for undergoing treatment with curative intent was 1.88 (1.58-2.23). Kaplan-Meier analysis indicated higher survival rates for young patients across all stages, but only marginally in stages IIIB-IV.

Young patients diagnosed with lung cancer are less likely to be diagnosed in a curable stage. The pathology and smoking habits differ significantly from patients above fifty years. While pending screening is important for the older population of smokers, it remains essential to consistently address the need for early diagnosis in the young population to prevent exacerbating existing disparities.