Introduction : an essential prerequisite of non-angiogenic growth appears to be the ability of the tumor to preserve the parenchymal structures of the host tissue. This morphological feature is visible on a routine haematoxylin-eosin tissue section (HE). The aim of this study was to determine the prognostic value of growth patterns in non-small-cell lung cancer (NSCLC).
Materials and Methods : HE tissue sections from 283 patients with NSCLC were analyzed together with their independently gathered clinical data. Tumors were classified morphologically into three growth patterns: destructive (angiogenic), papillary (intermediate) and alveolar (non-angiogenic). The mean follow-up of the whole group was 42 months with a standard error of mean of 1.8 months. A multiple Cox regression model was used to test the prognostic value of growth patterns together with other relevant clinicopathological factors for overall survival (OS) and disease-free survival (DFS).
Results : multiple Cox regression showed that growth pattern (p=0.007), stage (p=0.017), age (p=0.042) and type of operation (p=0.018) were independent prognostic factors for OS whereas growth pattern (p=0.001) and stage (p 0.001) were independent prognostic factors for DFS. For resected stage I NSCLC, alveolar growth pattern was the only independent predictor of early relapse (HR=2.207, 95% confidence interval (C.I.)=1.174-4.149, p=0.014), and alveolar (HR=2.217, C.I.=1.185-4.146, p=0.013) and papillary (HR=2.300, C.I.=1.183-4.470, p=0.014) growth pattern were the strongest independent predictors for early death.
Conclusion : the proposed classification has an independent prognostic value for OS as well as for DFS, providing a possible explanation for survival differences of patients in the same disease stage.