Prognostic significance using histologic subtype in stage I lung adenocarcinoma.

Background: The pathologic feature of lung adenocarcinoma is extremely complex because the prognosis of same-stage lung adenocarcinoma significantly differs because of pathological diversity. This study aimed to evaluate the clinical association between histologic subtype and recurrence. Further, the prognostic significance of histologic subtype in stage I lung adenocarcinoma was examined.

Methods: The medical records of 752 patients with pathological stage I lung adenocarcinoma were reviewed. The size of each histologic subtype was assessed. Receiver operating characteristic curve analysis was performed to identify the prognostic significance of histologic subtype. Univariate and multivariate analyses were conducted to validate the prognostic role of recurrence indicator.

Results: The median age of the participants was 64 years, and female patients were predominant. The acinar-predominant subtype (44.7%) was the most common. According to each subtype size for predicting recurrence, >1 cm size of acinar subtype showed significant difference and the only presence of micropapillary and solid subtype themselves showed significant difference. As the area under the receiver operating characteristic curve for recurrence, an acinar subtype size of >1 cm, or the presence of the micropapillary or solid subtypes was 0.710 (P<0.001). This variable was significant for recurrence in the multivariate analysis (P<0.001).

Conclusions: The presence of micropapillary, solid subtype or an acinar size of >1 cm are an independent prognostic factor of stage I lung adenocarcinoma. A more sizable acinar subtype affects the prognosis of stage I lung adenocarcinoma. This factor can provide additional information for predicting prognosis and can be a valuable supplement for the current classification.