Primary pulmonary enteric adenocarcinoma: A single-institute retrospective study on its imaging classification and...

As an extremely rare independent pathological subtype of lung adenocarcinoma, PEAC exhibits potentially distinct clinicopathological, radiological, and molecular characteristics. Currently, there were no large-sample studies reporting its features.

Patients with PEAC who underwent surgical resection from March 2013 to December 2023 were included in the study. The clinicopathological, imaging features, radiological subtypes and recurrence patterns were analyzed. Recurrence-free survival (RFS) and overall survival (OS) were assessed by Kaplan-Meier curves and compared between groups using log-rank tests. Cox proportional hazards models were used to assess associations with outcomes.

The final study population consisted of 81 patients (mean age, 63 years; age range, 36-79 years) including 60 men and 21 women. Radiologically, lesion subtypes were categorized as part-solid (6.2 %, 5/81), pure-solid (90.1 %, 73/81), and pneumonic-type PEAC (3.7 %, 3/81). Pneumonic-type PEACs were more prevalent in higher clinical T stages, whereas all part-solid PEACs were confined to the T1 stage (P = .001). In the part-solid subtype group, both RFS and OS rate were significantly higher than those in the pneumonic-type group and the pure-solid group (P = .001 and P = .0095). Tumor-node-metastasis(TNM) stage III emerged as an independent risk factor for recurrence (hazard ratio, 4.699 [95 % confidence interval: 1.967, 11.080]; P < .001). Pathological nodal involvement (hazard ratio, 24.301 [95 % confidence interval: 5.172, 114.195]; P < .001) was as independent predictor of poor OS. Intrapulmonary metastasis was identified as the predominant recurrence pattern in PEAC.

PEAC had distinct imaging characteristics. Survival outcomes vary significantly across different imaging subtypes, with prognosis largely determined by TNM stage.