Prior Extrapulmonary Malignancy and Outcomes After Lung Cancer Resection

Background/Aim: With the aging population, thoracic surgeons increasingly encounter patients with primary lung cancer who have a history of prior extrapulmonary malignancy (PEM). We investigated whether PEM independently compromises survival after curative-intent lung cancer resection and whether any difference is explained by impaired cancer control or competing mortality. Patients and Methods: We retrospectively analyzed 1,857 consecutive lung cancer resections performed in 2017-2018 at 12 Yokohama City University-affiliated institutions. After exclusion of 74 patients with prior lung cancer only, 1,783 patients remained: 505 in the PEM group and 1,278 in the no prior extrapulmonary malignancy (NPEM) group. Overall survival (OS), recurrence-free survival (RFS), inverse probability of treatment weighting (IPTW)-adjusted outcomes, and Fine-Gray competing-risk analyses were evaluated. Results: Compared with the NPEM group, the PEM group was older and included higher proportions of men, ever-smokers, patients diagnosed during surveillance for other diseases, and patients treated with limited resection. Unadjusted 5-year OS was 80.43% in the PEM group and 81.42% in the NPEM group (p=0.092), whereas 5-year RFS was 68.76% and 68.52%, respectively (p=0.983). PEM was not independently associated with OS [hazard ratio (HR)=1.046, 95% confidence interval (CI)=0.825-1.326, p=0.712] or RFS (HR=0.970, 95%CI=0.798-1.178, p=0.756). IPTW-adjusted analyses were concordant. Fine-Gray models showed no significant association between PEM and lung cancer-related death or non-lung-cancer death. Conclusion: PEM did not independently worsen postoperative cancer control or survival after lung cancer resection. Curative-intent surgery should therefore be considered according to the biology and operability of the current lung cancer rather than prior cancer history alone.