Prognostic Implication of Direct Cardiac Invasion from Lung Cancer in Non-Operatively Treated Patients Based on Lung Computed Tomography Imaging

Abstract

Background: Lung cancer with direct cardiac invasion (LCCI⁺) exerts a significant influence on the survival of patients. There is a paucity of comparative research into the prognosis of advanced lung cancer with and without direct cardiac invasion.

Method: In this study, 50 LCCI⁺ patients and 50 sex-, age-, and TNM stage-matched patients without direct cardiac invasion (LCCI^-) were retrospectively analysed. LCCI⁺ was defined as lung cancer directly invading the heart by penetrating mediastinum or extending into the atrium via the pulmonary vein. The study endpoint was all-cause death. In this study, the survival time was defined as the time from the first detection of direct cardiac invasion to the end of the event.

Results: During a median follow-up period of 31 months, all-cause death occurred in 44 patients (88.0%) in the LCCI⁺ group and in 36 patients (72.0%) in the LCCI^- group; the overall survival (OS) time among patients in the LCCI⁺ group was significantly lower compared with those in the LCCI^- group (5.0 [interquartile range (IQR), 2.0-12.0] vs 13.8 [IQR, 4.0-18.4] mo; p<0.001); the OS rate in the LCCI⁺ group was significantly lower compared with patients in the LCCI^- group (log-rank, p=0.0002). Multivariate Cox regression analysis showed that direct cardiac invasion was an independent predictor of survival in patients with advanced lung cancer (hazard ratio, 2.255; 95% confidence interval, 1.443-3.524). Further analysis indicated that in patients with small cell lung cancer, the survival rate between the LCCI⁺ group and LCCI^- group was insignificant (log-rank, p=0.075; survival time: 4.0 [IQR, 2.0-11.5] vs 11.5 [IQR, 5.0-18.3] mo); in patients with non-small cell lung cancer (NSCLC), the survival rate in the LCCI⁺ group was lower than that of the LCCI^- group (log-rank, p=0.01; survival time: 6.0 [IQR, 3.0-13.3] vs 16.3 [IQR, 10.4-27.2] mo).

Conclusions: Direct cardiac invasion from lung cancer was an independent prognostic factor for survival time in patients with lung cancer. Patients with direct cardiac invasion by NSCLC have a poorer clinical outcome than those without direct cardiac invasion. A careful preoperative evaluation is mandatory and appropriate management of cardiac involvement should be considered in the treatment of NSCLC.

Keywords: Advanced lung cancer; Cardiac metastases; Cardio-oncology; Prognosis.