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Analysis of pre-operative variables for identifying patients who might benefit from upfront cytoreductive nephrectomy for metastatic renal cell carcinoma in the targeted therapy era.

OBJECTIVE
The aim of the study is to identify pre-operative variables for selection of patients who would benefit from upfront cytoreductive nephrectomy for metastatic renal cell carcinoma.


METHODS
We reviewed the medical records of 171 patients who were presented with synchronous metastatic renal cell carcinoma and who had received no systemic therapy before enrollment. Of these, 96 underwent cytoreductive nephrectomy followed by targeted therapy (cytoreductive nephrectomy group) and 75 treated with targeted therapy alone (non-cytoreductive nephrectomy group). A Cox proportional hazards regression model was used to estimate the prognostic significance of pre-operative characteristics predicting overall survival in the cytoreductive nephrectomy group. The significant variables were designated as pre-operative factors to identify patients who would benefit from cytoreductive nephrectomy.


RESULTS
The median overall survival was 19.9 and 11.7 months in the cytoreductive nephrectomy and non-cytoreductive nephrectomy groups (P < 0.001). Karnofsky performance status (<80; hazard ratio 9.497, P < 0.001), hemoglobin (less than lower limit of normal; hazard ratio 1.913, P = 0.025), neutrophils (greater than upper limit of normal; hazard ratio 6.533, P < 0.001) and clinical N stage (N2; HR 2.714, P = 0.001) were independent pre-operative risk factors of mortality. Only those patients with risk factor <2 who had undergone upfront cytoreductive nephrectomy had a better median overall survival than patients who received targeted therapy alone (28.2 vs. 18.4 months, P = 0.018).


CONCLUSIONS
Four pre-operative risk factors (Karnofsky performance status, hemoglobin, neutrophils and clinical N stage) were identified as suitable for selection of patients who would not benefit from undergoing cytoreductive nephrectomy.