Adenosquamous Carcinoma of the Lung: Survival, Radiologic Findings, PD-L1, and Driver Mutations.

Adenosquamous carcinoma of the lung (ASC) is a rare non-small-cell lung cancer (NSCLC) subtype combining components of squamous cell carcinoma (SCC) and adenocarcinoma (AC). Data on ASC, particularly in Caucasian populations, are limited. We reviewed clinicopathological and radiological characteristics of ASC patients diagnosed between 1996 and 2023. Patients were classified into AC-predominant ASC (AC-ASC) and SCC-predominant ASC (SCC-ASC) groups for analysis. Among the 66 patients included, the median overall survival was 41.7 (95% CI, 25.0-54.4), while it was 48.1 (95% CI, 27.3-88.0) in patients treated with curative surgery (n = 44) and 15.3 (95% CI, 6.5-42.6) months for palliative patients (n = 22). The five-year survival rates were 39% and 26%, respectively. Recurrence occurred in 43% of stage I patients and was associated with worse survival (HR 3.303 (95% CI, 1.10-9.89) = 0.033). AC-ASCs (n = 17) more frequently showed air-bronchogram ( = 0.002) and pleural effusions ( = 0.054) compared to SCC-ASCs (n = 26). SCC-ASCs exhibited more vascular invasion ( = 0.006) and PD-L1 values between 1 and 49% (TPS) ( = 0.032). The subtype did not influence survival. EGFR and ALK alterations were found in 17% and 2% of patients, respectively. Despite early-stage disease, ASC patients had a high recurrence rate, associated with worse survival. Clinicopathologic differences between AC-ASCs and SCC-ASCs did not influence survival.