Distinctive characteristics of non-small cell lung cancer in the young: A SEER analysis of patients under 40 years old

Abstract

7621 Background: Non-small cell lung cancer (NSCLC) is diagnosed at a median age of 65 and is rare in younger people. The presentation and natural history of the disease in younger patients (age < 40) may not be the same as in typical, or older patients (age > 40). Methods: We identified in the SEER (Suveillance Epidemiology and End Results) registry, all patients diagnosed with NSCLC from 1990 to 2005. Patients were grouped by age at diagnosis, < 40 or = 40. Data on gender, cell type, extent of disease, overall survival, and cause of death were obtained from the SEER database. Cancer-specific survival was defined as time to death from cancer, in which case deaths from other causes are counted as censoring events. Results: In the SEER registry, 3,421 patients with NSCLC diagnosed at an age < 40 were identified, along with 323,566 patients age > 40. Younger patients were more likely to be women, 48% vs 43% (p < 0.0001), and more likely to present with distant disease 53% vs 49% (p < 0.0001). Adenocarcinoma and other, or non-specified types of NSCLC were more common in younger patients, 38% and 44% respectively, vs. 35% and 32% in the older patients. Squamous cell carcinoma was far less common in younger patients, 8.5% vs 23.5% in older patients (p<0.0001 for all comparisons). Overall and cancer specific survivals were higher for the younger cohort within each stage group. For example, 3 year overall survival for patients with distant (metastatic) disease was 8.8% in the younger patients and 4.7% in the older patients. For local disease, 5 year cancer specific suvivals were 92% in the younger patients and 62% in the older patients. Conclusions: Patients with NSCLC who are < 40 years old at diagnosis are more likely to be women and have adenocarcinoma and far less likely to have squamous cell carcinoma. Overall and cancer-specific survivals are better in these younger patients. No significant financial relationships to disclose.