Visceral Pleural Invasion Remains a Size-Independent Prognostic Factor in Stage I Non-Small Cell Lung Cancer

Background. The prognostic effect of visceral pleural invasion remains controversial when a tumor is less than 3 cm in stage I non-small cell lung cancer patients. We conducted this meta-analysis to evaluate the prognostic impact of visceral pleural invasion in these early patients. Methods. We searched PubMed, EMBASE, Cochrane Library, and China National Knowledge Infrastructure and included published studies on the prognostic significance of visceral pleural invasion in stage I non-small cell lung cancer. Meta-analysis was performed and heterogeneity and publication bias were also evaluated. Results. Twenty-two studies were included in the meta-analysis. In all stage I patients, visceral pleural invasion was associated with death (hazard ratio1.427; p = 0.000) and recurrence (hazard ratio1.600; p = 0.000). In subgroup analyses, visceral pleural invasions were consistently associated with death in each tumor size subgroup and recurrence in tumor less than 3 cm subgroup. Publication bias was not found. Conclusions. Visceral pleural invasion is a size-independent poor prognostic factor in stage I non-small cell lung cancer patients. We suggest adjuvant treatment should be considered in stage I patients with visceral pleural invasion. (C) 2015 by The Society of Thoracic Surgeons