Cardiovascular comorbidities and their prognostic value in small cell lung cancer patients with chemoradiotherapy.

Background: Small cell lung cancer (SCLC) is an extremely malignant subtype of lung cancer because of its high potential for metastases. Cardiac invasion of SCLC is a serious concern that may lead to systemic embolism or tract obstruction. It has aroused much concern that cardiovascular comorbidities may significantly affect the survival of SCLC patients and their treatment decisions.

Methods: We consecutively recruited 772 small cell lung cancer (SCLC) patients between January 2011 and December 2018 from 4 cancer specialty hospitals in China. Only newly diagnosed primary cancer inpatients were included. Univariable and multivariable adjusted Cox proportional hazard models were conducted to evaluate the risk factors associated with mortality. Hazard ratios (HRs) for mortality and corresponding 95% confidence intervals (95% CIs) were calculated.

Results: The prevalence of cardiovascular diseases (CVDs) was 34.6% in all SCLC patients. Log-rank analysis presented statistically significant differences in median survival time (MST) between patients with CVD and without CVD in all SCLC patients (9.0 months vs. 15.0 months, P = 0.005) and patients with chemotherapy only (12.0 months vs. 18.0 months, P = 0.048). Pericardial effusion (HR 1.671, 95% CI 1.082-2.580, P = 0.021) and heart failure (HR 1.752, 95% CI 1.290-2.379, P < 0.001) were independent risk factors associated with mortality in all SCLC patients. VTE is related to poorer prognosis in patients with chemotherapy only (HR 5.558, 95% CI 1.335-23.135, P = 0.018) and chemoradiotherapy (HR 3.057, 95% CI 1.270-7.539, P = 0.013).

Conclusions: Comprehensive management of CVD comorbidities is of vital importance for the long-term prognosis of SCLC patients.