Tumor Mass Is a Better Prognostic Factor Than Consolidation-to-Tumor Ratio in Invasive Lung Adenocarcinoma Manifest...

To evaluate the long-term prognosis and related factors in patients who manifest part-solid invasive lung adenocarcinoma with difficult-to-measure solid portions.

Patients with resected clinical stage I part-solid invasive lung adenocarcinoma in a single institution were retrospectively enrolled. They were divided into measurable and difficult-to-measure groups according to whether the radiologically solid portion was difficult to measure. The Kaplan-Meier method was used to evaluate the outcomes. Cox analysis was used to explore the prognostic factors. Tumor nodules were segmented using 3D Slicer software to extract quantitative features.

Of the 1240 patients, 225 (18.2%) were classified into the difficult-to-measure group. The intraclass correlation coefficient revealed that two readers had an excellent agreement on solid size in the measurable group (0.88), but not in the difficult-to-measure group (0.65). Compared with the measurable group, these tumors were larger and exhibited comparable overall survival (10 y 95.0% versus 94.2%; p = 0.341). The prognosis of the difficult-to-measure group was similar to that of cT1a or cT1b in the measurable group. consolidation-to-tumor ratio was an independent risk factor for patients with easy-to-measure solid components but not for patients whose solid parts were difficult to measure. Multivariate analyses revealed that tumor mass (>1.62 g) was an independent factor for worse recurrence-free survival in the measurable or difficult-to-measure group.

Patients with invasive adenocarcinoma manifesting as part-solid nodules whose solid components were difficult to measure revealed favorable outcomes. Tumor mass was a better prognostic indicator than consolidation-to-tumor ratio for this population.