Background: Previous studies concerning the impact of prior cancer on newly diagnosed lung cancer are mainly based on databases and obtained mixed results. Utilizing a large study population, we aimed to reveal this impact.
Patients and methods: Lung cancer patients from January 2008 to April 2021 were enrolled. The Kaplan-Meier method was used to perform survival analyses. To investigate the impact of prior cancer, a Cox proportional hazards model was conducted. To minimize the influence of the heterogeneity of prior cancer, stratified analyses were carried out.
Results: In total, 17,423 lung cancer patients were reviewed, among which we identified 1469 (8.4%) patients with a history of prior cancer. Cox regression analysis revealed that prior cancer was an independent poor prognostic factor on overall survival (HR = 1.430, 95% CI: 1.147-1.784, p = 0.001) but did not affect lung cancer-specific survival (HR = 1.120, 95% CI: 0.876-1.434, p = 0.366). Interestingly, in further stratified analyses, we found that prior cancer history affected overall survival only in pTNM stage 0/I patients (HR = 1.670, 95% CI: 1.247-2.237, p = 0.001), but not in pTNM stage II/III/IV patients (HR = 1.237, 95% CI: 0.877-1.743, p = 0.226). Similarly, prior cancer was an independent poor prognostic factor on overall survival only for pN0 patients. Subsequently, subgroup analyses indicated that the impact of prior cancer varied in pTNM stage 0/I patients according to the type of prior cancer and the interval time.
Conclusions: Considering that prior cancer affects overall survival in patients with clinically curable lung cancer, clinicians should pay attention to this effect and improve the management of these patients to achieve a better prognosis.
© 2023. Society of Surgical Oncology.