AIMS

We investigated the relationship between predominant subtype, according to the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society International Multidisciplinary Lung Adenocarcinoma Classification, and prognosis in stage I lung adenocarcinoma in Zhejiang Cancer Hospital.

METHODS

Two hundred and sixty-one patients with stage I lung adenocarcinoma, operated in Zhejiang Cancer Hospital, were identified between 2000 and 2010. Survival curves were plotted using the Kaplan-Meier method. The Cox proportional hazard model was used for multivariate analysis.

RESULTS

None of the cases were adenocarcinoma in situ and six were minimally invasive adenocarcinomas. Two hundred and fifty-five cases were invasive adenocarcinoma. Of those, 80, 76, 42, 34, 19, and 4 were papillary predominant, acinar predominant, micropapillary predominant, solid predominant, lepidic predominant subtypes, and variants of invasive adenocarcinoma, respectively. Patients with micropapillary and solid predominant tumors had a significantly worse disease-free survival as compared to those with other subtypes predominant tumors (p < 0.001). Multivariate analysis revealed that the new classification was an independent predictor of the disease-free and overall survival (p = 0.002 and 0.015).

CONCLUSION

The predominant subtype in the primary tumor was associated with prognosis in resected stage I lung adenocarcinoma.