Effect of reclassification of the IMDC model in patients with metastatic renal cell carcinoma treated with targeted therapy in the first-line and second-line settings.

<bold>Purpose: </bold>To investigate the prognostic effect of the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) model reclassification after targeted therapy administration in metastatic renal cell carcinoma (mRCC).<bold>Patients and Method: </bold>A total of 245 mRCC patients treated with targeted therapy are included. The IMDC model reclassification is performed at 1 month after treatment induction of both first-line and second-line targeted therapy.<bold>Results: </bold>Of the 245 patients, 74 (30.2%) are divided into different risk groups by the IMDC model reclassification after first-line targeted therapy, and patients newly classified with intermediate risk tend to have better overall survival than those remaining in the primary poor-risk group (P = 0.018). Of the 119 patients treated with subsequent second-line targeted therapy, 25 (21.0%) are divided into different risk groups by the IMDC model reclassification after second-line targeted therapy, and patients newly classified with poor risk tend to have increased all-cause mortality compared with those remaining in the primary intermediate-risk group (P = 0.007), whereas patients newly classified with intermediate risk tend to have better overall survival than those remaining in the primary poor-risk group (P = 0.034).<bold>Conclusion: </bold>Approximately a quarter of the mRCC patients are classified into different risk groups of the IMDC model following targeted therapy administration in the first-line and second-line settings. There is a significant difference in overall survival of subgroups after the IMDC model reclassifications. [ABSTRACT FROM AUTHOR]