Objectives: Pathological vessel invasion is a well-known prognostic factor in early-stage, non-small cell lung cancer and preoperative predicting vessel invasion may enable us to improve prognosis by additional interventions. We evaluated the importance of vessel invasion as a prognostic factor in clinical stage IA non-small cell lung cancer and predictive performance of simple diameter-based computed tomography image analysis for vessel invasion.
Methods: The study design was retrospective, and we reviewed 398 patients who underwent surgical resection of clinical stage IA non-small cell lung cancer from 1999 to 2009. The prognostic factors for recurrence-free survival were examined by univariate and multivariate analyses. Additionally, we analyzed preoperative high-resolution computed tomography images of patients with adenocarcinoma. The greatest diameter of the tumor in the lung window and the length of the consolidation part of L in the mediastinal window were measured. Then the ratio (mediastinal window/lung window) was calculated, and the correlation between the ratio (mediastinal window/lung window) and vessel invasion was analyzed by receiver operating characteristic analysis.
Results: Sixty-eight recurrences occurred. Multivariate analysis revealed that vessel invasion, high preoperative serum carcinoembryonic antigen, and history of other malignancy were independent prognostic factors; their hazard ratios were 2.98, 2.45, and 1.98, respectively. The receiver operating characteristic analysis showed that the area under the curve was 0.75. When we set the cut-off value of the ratio (mediastinal window/lung window) at 0.67, the sensitivity and specificity were 75% and 72%, respectively.
Conclusions: Vessel invasion had the greatest impact on recurrence in clinical stage IA non-small cell lung cancer. Our simple computed tomography image analysis showed good predictive performance for vessel invasion.