TY - JOUR
T1 - The association between metformin use and oncologic outcomes among surgically treated diabetic patients with localized renal cell carcinoma
AU - Psutka, Sarah P.
AU - Boorjian, Stephen A.
AU - Lohse, Christine M.
AU - Stewart, Suzanne B.
AU - Tollefson, Matthew K.
AU - Cheville, John C.
AU - Leibovich, Bradley C.
AU - Thompson, R. Houston
N1 - Publisher Copyright:
© 2014 Elsevier Inc.
PY - 2015/2/1
Y1 - 2015/2/1
N2 - Metformin inhibits renal cell carcinoma (RCC) cell proliferation both in vitro and in vivo; however, clinical data regarding the effect of metformin in patients with RCC are lacking. We evaluated the association of metformin use with outcomes among patients with surgically treated localized RCC. Materials and methods: We identified 283 consecutive diabetic patients treated surgically for localized RCC between January 1, 1994 and December 31, 2008. Clinicopathologic features were compared between patients exposed to metformin (n = 83, 29%) and those who were not (n = 200, 71%). Progression-free, cancer-specific, and overall survival rates were estimated with the Kaplan-Meier analysis, and Cox models were used to evaluate the association of metformin use with outcomes. Results and conclusions: Patients receiving metformin had a better renal function (median estimated glomerular filtration rate = 65 vs. 55ml/min/1.73m2, P<0.001), performance status (Eastern Cooperative Oncology Group<1: 89% vs. 71%, P = 0.001), and lower Charlson comorbidity index (median = 2 vs. 3, P = 0.02) compared with those who did not, but were otherwise similar across other clinicopathologic features (P>0.05 for all). At a median postoperative follow-up of 8.1 years, patients exposed to metformin had similar 5-year progression-free (80% vs. 75%, P = 0.6) and cancer-specific survival rates (91% vs. 81%, P = 0.16), but significantly improved overall survival rate (79% vs. 62%, P = 0.01). However, metformin was not independently associated with the risks of progression, RCC-specific mortality, or all-cause mortality on multivariable analyses. In this surgical cohort of diabetic patients with M0 RCC, preoperative metformin exposure was associated with improved overall survival on unadjusted analysis. Although metformin was not independently associated with oncologic or survival outcomes, future studies appear warranted.
AB - Metformin inhibits renal cell carcinoma (RCC) cell proliferation both in vitro and in vivo; however, clinical data regarding the effect of metformin in patients with RCC are lacking. We evaluated the association of metformin use with outcomes among patients with surgically treated localized RCC. Materials and methods: We identified 283 consecutive diabetic patients treated surgically for localized RCC between January 1, 1994 and December 31, 2008. Clinicopathologic features were compared between patients exposed to metformin (n = 83, 29%) and those who were not (n = 200, 71%). Progression-free, cancer-specific, and overall survival rates were estimated with the Kaplan-Meier analysis, and Cox models were used to evaluate the association of metformin use with outcomes. Results and conclusions: Patients receiving metformin had a better renal function (median estimated glomerular filtration rate = 65 vs. 55ml/min/1.73m2, P<0.001), performance status (Eastern Cooperative Oncology Group<1: 89% vs. 71%, P = 0.001), and lower Charlson comorbidity index (median = 2 vs. 3, P = 0.02) compared with those who did not, but were otherwise similar across other clinicopathologic features (P>0.05 for all). At a median postoperative follow-up of 8.1 years, patients exposed to metformin had similar 5-year progression-free (80% vs. 75%, P = 0.6) and cancer-specific survival rates (91% vs. 81%, P = 0.16), but significantly improved overall survival rate (79% vs. 62%, P = 0.01). However, metformin was not independently associated with the risks of progression, RCC-specific mortality, or all-cause mortality on multivariable analyses. In this surgical cohort of diabetic patients with M0 RCC, preoperative metformin exposure was associated with improved overall survival on unadjusted analysis. Although metformin was not independently associated with oncologic or survival outcomes, future studies appear warranted.
KW - Diabetes
KW - Metformin
KW - Mortality
KW - Recurrence
KW - Renal cell carcinoma
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U2 - 10.1016/j.urolonc.2014.07.008
DO - 10.1016/j.urolonc.2014.07.008
M3 - Article
C2 - 25153774
AN - SCOPUS:84923600700
SN - 1078-1439
VL - 33
SP - 67.e15-67.e23
JO - Urologic Oncology: Seminars and Original Investigations
JF - Urologic Oncology: Seminars and Original Investigations
IS - 2
ER -