Impact of sunitinib treatment on blood glucose levels in patients with metastatic renal cell carcinoma.

OBJECTIVE: To investigate the effects of sunitinib treatment on blood glucose levels in patients with metastatic renal cell carcinoma. METHODS: We reviewed the records of 48 patients who received sunitinib treatment for metastatic renal cell carcinoma between April 2007 and December 2010 at our institution. Patients' data including diabetic status, diabetes mellitus medication and mean blood glucose levels before, during and after the treatment with sunitinib were assessed. RESULTS: In 10 of the 48 (20.8%) patients who were diabetic, the blood glucose level was observed to be significantly decreased after 4 weeks of sunitinib treatment with the mean decrease in blood glucose level being 76.1 ± 29.0 mg/dl (P = 0.002). Subsequently, after a 2-week off-treatment period, the mean blood glucose level rebound and increased (21.9 ± 6.3 mg/dl, P = 0.038) in these 10 patients. With sunitinib treatment, one patient was able to discontinue diabetes mellitus medication completely during a 4-week treatment period, and three other patients had dosages of their oral diabetes mellitus medication reduced. Among 38 non-diabetic patients, no significant changes in blood glucose levels were observed during both the 4-week sunitinib treatment period and the 2-week off-treatment period. No severe hypoglycemic episode was observed among our subjects. CONCLUSIONS: Sunitinib treatment in diabetic patients with metastatic renal cell carcinoma may result in significantly decreased blood glucose levels. Thus, blood glucose levels should be checked more vigilantly in diabetic patients undergoing sunitinib treatment to adjust diabetes mellitus medications as needed. Further investigation via a larger scaled, prospective study would be needed.