Survival after second primary lung cancer

Abstract

BACKGROUND: Lung cancer accounts for the largest absolute risk of second malignancies among Hodgkin lymphoma (HL) survivors. However, no population-based studies have compared overall survival (OS) between HL survivors who developed nonsmall cell lung cancer (HL-NSCLC) versus patients with first primary NSCLC (NSCLC-1). METHODS: The authors compared the OS of 178,431 patients who had NSCLC-1 and 187 patients who had HL-NSCLC (among 22,648 HL survivors), accounting for sex, race, sociodemographic status, calendar year, and age at NSCLC diagnosis, and NSCLC histology and stage. All patients were reported to the population-based Surveillance, Epidemiology, and End Results Program. Hazard ratios (HRs) were derived from a Cox proportional hazards model. RESULTS: Although the NSCLC stage distribution was similar in both groups (20% localized, 30% regional, and 50% distant), HL survivors experienced significantly inferior stage-specific OS. For patients with localized, regional, and distant stage NSCLC, the HRs (95% confidence interval [CI]) for death among HL survivors were 1.60 (95% CI, 1.08-2.37; P < .0001), 1.67 (95% CI, 1.26-2.22; P ¼ .0004), and 1.31 (95% CI, 1.06-1.61; P ¼ .013), respectively. Among HL-NSCLC patients, significant associations were observed between more advanced NSCLC stage and the following variables: younger age at HL diagnosis (P ¼ .003), younger age at NSCLC diagnosis (P ¼ .048), and longer latency between HL and NSCLC diagnoses (P ¼ .015). CONCLUSIONS: Compared with patients who had de novo NSCLC, HL survivors experienced a significant 30% to 60% decrease in OS after an NSCLC diagnosis. Further research is needed to not only elucidate the clinical-biologic underpinnings of NSCLC after HL, including the influence of previous HL treatment, but also to define the role of lung cancer screening in selected patients.