Study of the radiologic and pathologic correlations for subsolid lung adenocarcinoma with the application of whole-mount sections (ECTOP1011).

Abstract

Background: The radiologic and pathologic correlations of subsolid lung cancers are unclear. No study has used the whole-mount sections to analyze the correlations. This study aims to clarify the radiologic and pathologic correlations through the use of the whole-mount sections analysis.

Methods: Patients with subsolid lung adenocarcinomas receiving segmentectomy or lobectomy were included. The whole-mount sections were made. The same radiologic and pathologic sections were identified. Radiologic and pathologic tumor and solid/invasive sizes were compared. Histologic features in the solid component and ground-glass opacity (GGO) regions were evaluated.

Results: There were 102 patients with 20 pure GGO and 82 part-solid tumors analyzed. There was one adenocarcinoma in situ, 32 minimal invasive adenocarcinomas, and 69 invasive adenocarcinomas. For all patients or patients with the matched sections, radiologic tumor diameter was larger than pathologic one (P<0.001; P=0.009), while radiologic solid component diameter was smaller than that of pathologic invasive diameter (P=0.01; P<0.001). The clinical T stage was pathologically upstaged in nearly 50% of patients. For pure GGO tumors, prevalence of lepidic, acinar, and papillary subtypes was 100.0%, 84.2%, and 47.4%, with no micropapillary or solid subtype. For part-solid tumors, in the GGO region, prevalence of lepidic, acinar, papillary, and micropapillary subtypes was 100.0%, 83.3%, 57.1%, and 11.9%, no solid subtype existed. In the solid region, prevalence of lepidic, acinar, papillary, micropapillary, and solid subtypes was 19.0%, 95.2%, 59.5%, 26.2%, and 2.3%.

Conclusions: For subsolid lung cancers, the pathologic invasive size was radiologically underestimated. There were acinar/papillary, but no micropapillary subtype in pure GGO tumors. In part-solid tumors, there were micropapillary subtypes in GGO region and micropapillary/solid subtypes in solid region.