Cancer-associated thromboses in non-small cell lung cancer patients with epidermal growth factor receptor mutation.

Introduction: The purposes of this study were to clarify whether non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) gene mutation have a higher incidence of cancer-associated venous and arterial thrombosis/thromboses (CATs) than EGFR-negative patients, and whether patients who develop CATs have a significantly poorer survival. Material and methods: The relationship between EGFR mutation and the development of CATs was evaluated retrospectively in 1,891 patients with NSCLC, including 381 who were EGFR-positive. Propensity matching and logistic regression analysis were performed. Results: Among 1,891 patients with NSCLC, 37 patients (2.0%) developed CATs. After propensity matching, the incidence of CATs was 3.9% in EGFR-positive patients and 0.9% in EGFR-negative patients (p = 0.011). Therefore, the risk of developing CATs was higher in EGFR-positive than EGFR-negative patients. In EGFR-positive patients, the most common time to develop CATs was at the time of lung cancer diagnosis, but there were some patients who developed CATs during second-line treatment or later when EGFR-tyrosine kinase inhibitors were no longer effective. In advanced EGFR-positive patients, there was no significant difference in overall survival depending on the presence or absence of CATs, but the development of CATs impaired the long survival expected in EGFR-positive patients. Conclusions: EGFR-positive patients are currently treated with tyrosine kinase inhibitors and are expected to have a certain long-term prognosis. However, there is concern that overall survival might be shortened if CATs develop. Therefore, the possibility of developing CATs in EGFR-positive NSCLC patients must be addressed.