SAN FRANCISCO—The International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) model is predictive of patient survival after targeted therapy for metastatic renal cell carcinoma (mRCC), according to a validation study presented during the 2014 Genitourinary Cancers Symposium.
“The IMDC prognostic model has been validated in, and can be applied to, patients previously treated with targeted therapy, in addition to previously validated populations in first-line targeted therapy and non-clear cell settings,” reported Jenny J. Ko, of the Tom Baker Cancer Centre in Calgary, Alberta, Canada, and coauthors.
However, prognostic models for second-line systemic therapy “have not been studied in the setting of contemporary sequential targeted therapy,” the authors explained. “We sought to validate the IMDC prognostic model in patients with mRCC receiving next-line targeted therapy after progression on first-line targeted therapy.”
Data for patients at 19 centers were analyzed. “For patients who had immunotherapy (22%) prior to their first targeted therapy, we examined their second targeted (third-line) therapy,” the researchers noted. They assessed the IMDC model’s association with overall survival after initiation of second-line therapy.
For 1,021 patients treated with a second targeted therapy, median overall survival (OS) was 12.5 months (95% CI: 11.3-14.3 months) “with 369 (36.1%) of patients remaining alive,” the authors reported. Five of six IMDC model factors measured during second-line targeted therapy proved to be independently predictive of poor OS: anemia, thrombocytosis, neutrophilia, Karnofsky performance status less than 80%, and less than 1 year from diagnosis to treatment (all hazard ratios [HRs], 1.39-1.58; all Ps < 0.05).
“When patients were divided into three risk categories using IMDC criteria, median OS was 35.8 months (95% CI: 28.3-47.8 [months]) in the favorable risk group (n = 76), 16.6 months (95% CI: 14.9-17.9 [months]) in the intermediate risk group (n = 529), and 5.4 months (95% CI: 4.7-6.8 [months]) in the poor risk group (n = 261),” the coauthors reported.
Many of the study’s coauthors have previously published an external validation study of patients with mRCC treated with first-line vascular endothelial growth factor–targeted therapy, comparing the IMDC model’s prognostic power with other models, including the Cleveland Clinic Foundation model, the International Kidney Cancer Working Group model, French Model, and the Memorial Sloan-Kettering Cancer Center model.1 The study found that the IMDC model was more predictive of mortality risk at 2 years than other models, and the authors advocated its use for risk stratification and patient counseling.1
The 2014 Genitourinary Cancers Symposium is sponsored by the the American Society of Clinical Oncology (ASCO), the American Society for Radiation Oncology (ASTRO), and the Society of Urologic Oncology (SUO).
- Heng DY, Xie W, Regan MM, et al. External validation and comparison with other models of the International Metastatic Renal-cell Carcinoma Database Consortium Prognostic Model: a population-based study. Lancet Oncology. 2013;14(2):141-148.
- Ko JJ, Xie W, Heng DYC, et al. Abstract 398. Presented at: 2014 Genitourinary Cancers Symposium. Jan. 30-Feb. 1, 2014; San Francisco.