Clinical features at presentation, C-kit, and Her2/neu overexpression as prognostic factors in elderly patients with lung carcinoma

Abstract

9636 Purpose: To determine the clinical predictors of survival and significance of C-kit and Her2/neu overexpression as prognostic markers in elderly males (age =/>65 years) with lung carcinoma (LC). Methods: After approval from the institutional review board, a retrospective chart review was performed to obtain demographic/clinical data on elderly males with a biopsy-proven LC. C-kit and Her2/neu overexpression was also assessed using immunohistochemical techniques (IHC). Results: 64 elderly males (mean age: 73.75 years; range: 65–87 years) were included in our study. 12/64 patients (18.75%) had small cell lung cancer (SCLC) and 48 (75%) had non-small cell lung cancer (NSCLC). 4 patients (6.25%) refused diagnostic biopsies. The most common diagnostic procedures were CT-guided biopsy (n=38, 59.37%) and transbronchial biopsy (n=12, 18.75%). Of the 64 patients studied, 24 (37.5%) presented with cough, 16 (25%) as an incidental finding and 8 (12.5%) with dyspnea. Cox regression analysis revealed that patients with dyspnea at presentation had a 4.25 greater odds (95% CI 1.8–10, p=0.01) of early demise as compared with cough. With increasing performance status (from ECOG 0 to 4), the hazards of dying increased by 1.27 times the previous level (p=0.005). Interestingly, of the 12 patients with SCLC, 4 (33.3%) revealed C-kit overexpression, while none of the NSCLC specimens revealed overexpression. Also, after adjusting for confounding variables, C-kit overexpression was associated with a significant survival advantage (p=0.018) in SCLC, using the Log rank test. In contrast, presence of Her2/neu identified in 4 patients with SCLC (33.3%) and 9 NSCLC patients (18.75%) had an insignificant effect on survival (p=0.87) in elderly males with LC. Conclusions: Elderly males with LC represent a select subgroup with characteristic clinical and pathologic features. Her2/neu overexpression seen in NSCLC and SCLC lacks prognostic significance in elderly males. Interestingly, however, c-kit overexpression, seen in ∼30% of the SCLC cohort seems to confer a survival advantage. Further larger studies are needed to validate our findings. No significant financial relationships to disclose.