Microscopic Vascular Invasion May be Strong Predictor of Outcomes

Microscopic vascular invasion (MVI) may be a strong predictor of poorer outcomes in patients with non-small cell lung cancer (NSCLC), and the effect is more prominent in patients with tumors at least 5 cm in size, according to a Japanese study published in Chest Journal.¹

Yoshihisa Shimada, MD, PhD, of the Tokyo Medical University Hospital and fellow researchers looked at 1,884 patients with pT1-4NO-2 NSCLC who had undergone complete resection. They used Kaplan-Meier to estimate overall survival and recurrence-free proportion, while using the Cox proportional hazards model to assess for independent predictors of poor outcomes.

Among the observed patients, 1,097 were found to have MVI. Upon multivariate analysis, the researchers found that MVI was a significant independent predictor of unfavorable overall survival and recurrence.

Frequency of MVI differed according to tumor size, with the proportion of patients with 5-year recurrence-free period with tumor sizes between MVI-positive and MVI-negative being 93% and 72.5% with tumors 2 cm or less, 90.8% and 63.3% with tumors between 2 to 3 cm, and 86.4% and 59.9% with tumors 3 to 5 cm, respectively.

“Further analysis of survival and MVI should be collected for future revision of the TNM system,” the authors concluded.

Reference

1. Shimada Y, Saji H, Kato Y, et al. The frequency and prognostic impact of pathological microscopic vascular invasion according to tumor size in non-small cell lung cancer [published online ahead of print September 17, 2015]. Chest Journal. doi:10.1378/chest.15-0559.