Primary tumor location is an important predictor of survival in pulmonary adenocarcinoma

Purpose: The prognostic value of tumor location in pulmonary adenocarcinoma (ADC) is controversial. We compared the prognosis and relevant data between central-type ADC (CT-ADC) and peripheral-type ADC (PT-ADC) in order to identify the reasons for the different outcomes between them and to improve the treatment strategy and prognosis of these two types.

Patients and methods: Data of 256 patients with pathologically diagnosed ADC were retrospectively reviewed. The prognostic factors for disease-free survival (DFS), progression-free survival (PFS), and overall survival (OS) were analyzed using univariate and multivariate analyses.

Results: A total of 124 and 132 patients had CT-ADC and PT-ADC, respectively. CT-ADC was associated with an earlier age, poorer Karnofsky Performance Status (KPS), higher rates of advanced stage, bone metastasis, contralateral pulmonary metastasis, and pleural effusion. Besides, CT-ADC showed a trend toward lower rate of EGFR mutation. Patients with CT-ADC had a significantly shorter PFS/DFS and OS than did those with PT-ADC. Multivariate analysis revealed that advanced stage, central-type location, EGFR wild-type, no surgery, presence of COPD, and interstitial lung disease (ILD) were independent poor prognostic factors for OS. The rate of surgery was significantly lower in patients with CT-ADC. Among patients with ILD or COPD, OS is shorter in patients with central- than peripheral-type tumors.

Conclusion: CT-ADC is associated with poorer survival than PT-ADC and the lower rate of surgery in patients with CT-ADC is an important reason for this. Tumor location of pulmonary ADC plays a critical role in predicting prognosis and choosing therapeutic strategies.