Assessment of prognostic scores of brain metastases from lung adenocarcinoma with EGFR mutations

The aim of this study was to analyze prognostic factors and evaluate the value of four prognostic scores including RPA, DS-GPA BS-BM, GGS for the EGFR mutant BM patients from lung adenocarcinoma treated with EGFR-TKI. Data of NSCLC were retrospectively reviewed from August 2010 to June 2015 using the medical database of Shanxi Provincial Cancer Hospital. Patients with BM from lung adenocarcinoma with mutant EGFR treated by EGFR-TKI or a combination of EGFR-TKI and WBRT were included. Potential prognostic factors were statistically examined. The C-index of each prognostic score was calculated. A total of 1063 BM patients with lung adenocarcinoma that had been identified with EGFR mutations were reviewed. A total of 104 patients that had been diagnosed with BM were confirmed to have mutant EGFR in primary tumors. These patients received treatment with EGFR-TKI or EGFR-TKI with WBRT to BM. The potential predictive factors in multivariable analysis included KPS (70 vs.70–80 vs. 90–100) and number of brain metastatic lesions. In the log-rank test, the indexes of RPA, DS-GPA BS-BM, and GGS were all significant predictors of OS. The C-indexes of each prognostic score were 0.79, 0.76, 0.77, and 0.74 in DS-GPA, RPA, GGS, and BS-BM, respectively. The indexes of RPA, DS-GPA BS-BM, GGS were applicable for asessing survival stratification in brain metastases from lung adenocarcinoma with presented EGFR mutations in our independent population. The DS-GPA appears to be the best predictive value. However, all four of the indexes could not evaluate the exact independent prognostic factors in multivariable analysis. A prognostic index specific for this group of patients was needed for targeted lung cancer therapy.