Elevated increased blood pressure (hypertension) is a common, treatable side effect of antiangiogenic cancer therapies. Now, new study findings in more than 500 patients indicate that development of hypertension may predict therapy response in patients with advanced kidney cancer treated with the antiangiogenic drug Sutent® (sunitinib). Sutent is one of a number of approved cancer agents that block tumor blood vessel growth, and is approved to treat advanced kidney cancer, or renal cell carcinoma (RCC).
Researchers examined data from three clinical trials of Sutent in 544 patients with metastatic RCC. Hypertension in the analysis was defined as a maximum average systolic blood pressure (SBP) ≥ 140 mmHg and a maximum average diastolic blood pressure (DBP) ≥ 90 mmHg.
In the study, patients with a maximum SBP ≥ 140 mmHg had a median progression-free survival (the time a patient lives without his or her disease getting worse; PFS) of 12.5 months compared with 2.5 months in patients with a SBP < 140 mmHg. PFS in patients with a maximum DBP ≥ 90 mmHg was 13.4 months compared with 5.3 months in patients with DBP < 90 mmHg.
The same trend was also found for overall survival (OS). OS was 30.9 months in patients with SBP ≥ 140 mmHg compared with 7.2 months for patients without hypertension. For elevated DBP, OS was 32.2 months compared with 14.9 months for patients with DBP < 90 mmHg. Statistical analyses found that the occurrence of hypertension predicted improved survival significantly and independently of all other factors.
Study author Dr. Brian Rini of Cleveland Clinic’s Taussig Cancer Institute, Cleveland, Ohio, said that hypertension is a potential biomarker for predicting anti-tumor efficacy of Sutent for advanced kidney cancer. The findings were reported at the 2010 Genitourinary Cancers Symposium (ASCO-GU).
Advanced renal cell carcinoma, a rare but serious type of kidney cancer, is among the most treatment-resistant tumors. Nearly 58,000 people in the United States were diagnosed with kidney cancer in 2009.