Erythrocyte sedimentation rate kinetics as a marker of treatment response and predictor of prognosis in Chinese metastatic renal cell carcinoma patients treated with sorafenib

Objectives: Previous prognostic factor models for metastatic renal cell carcinoma (mRCC) have not included erythrocyte sedimentation rate (ESR). We designed the present study to evaluate the prognostic value of ESR for mRCC patients treated with sorafenib. Methods: Sorafenib was given to 83 patients with clear cell mRCC. Serum ESR was tested before treatment and every 4 weeks after first administration of sorafenib. Oncological evaluation was carried out every 8 weeks. Analyzed factors included age, sex, performance status, method of nephrectomy, number of metastatic organs, anemia, lactate dehydrogenase, corrected calcium, albumin, baseline ESR level and ESR kinetics status. Kaplan-Meier and Cox regression analyses on progression-free survival (PFS) were carried out. Results: Baseline ESR levels ranged from 3 to 154 mm/h, and 43 (41.0%) patients had an ESR level higher than 40 mm/h. Median PFS was 10.0 months (95% CI 7.6-12.4 months). Dividing the cohort into three groups according to ESR kinetics status, median PFS was 27 months in the decreased ESR group, 12 months in the stable ESR group and 6 months in the increased ESR group. Performance status, time from diagnoses to sorafenib treatment, number of metastatic organs and ESR kinetics were independent predictors for PFS in multivariable Cox regression model analysis, with an area under the curve of 0.865 in a binary logistic regression model of 12-month PFS probability. Conclusions: ESR kinetics can be useful to monitor the treatment response and to predict PFS for mRCC patients treated with sorafenib as second-line therapy.