Outcomes of Lung Cancer Treatment Choices Informed by Proteomic Test in Diversified Population

- Background: Proteomic (VeriStrat ) serum test has prognostic and predictive value in response to erlotinib; but the usefulness of this test in African Americans has not been studied yet. Here we studied effect of race on survival based on result of VeriStrat test signature. - Patients and Methods: In this phase-III clinical study we retrospectively reviewed electronic records of advanced (stages IIIB & IV) lung cancer patients from 09/2009 till 07/2014 who had done proteomic test to help with their therapy choices. Survival analysis was done using SAS software 9.4. Kaplan-Meier survivor test and multivariate cox proportional hazard models were used for data analysis. Covariates of VeriStrat test, treatment, race, histopathology, and Charlson Comorbidity Index (CCI) were used for statistical analysis. - Result: Among 49 qualified patients, 31 had done VeriStrat test before and 18 after their first line of anticancer therapy. Nineteen cases with VeriStrat good test signature (VSG) received erlotinib, and 12 received chemotherapy; 4 cases with VeriStrat poor signature (VSP) received erlotinib and 12 received chemotherapy. When stratified for test signature the overall survival did not differ between Whites (Hispanic and non-Hispanic) and African Americans (AA) (adjusted HR AA/Whites= 0.78 (95% CI=0.38-1.61; p=0.51)). There was a trend of better survival prognosis for combined effect of VSG and African American race. Confounding effect of CCI with VeriStrat test and race on survival outcome was estimated. A trend of better survival in patients with VSG signature was seen after adjusting the model for CCI (HR of 0.80 (95% CI=0.39-1.64)); confounding effect of CCI on VeriStrat test survival hazard was significant (0.007). Survival confounding effect of tumor histopathology and CCI-adjusted second line treatment was studied: the non-squamous cell tumors did not show any survival difference between erlotinib versus chemotherapy (CCI adjusted HR 2nd line tx = 2.18 (95%CI= 0.68-7.05)), but in squamous cell tumors an inferior outcome was observed in erlotinib group (CCI-adjusted HR 2nd line tx =7.82 (95% CI=1.2-51.2)). - Conclusion: Our study indicates that there is no significant impact of race on prognostic and predictive values of VeriStrat test. Second line treatment survival of squamous cell tumors showed inferiority of erlotinib compared to chemotherapy. Charlson Comorbidity Index was a significant confounding factor for survival effect of race and VeriStrat test. Result of this study has been published in Anticancer Research J. 2016 Apr; 36(4):1759-65. PMID: 27069156