“These authors looked at prognostic factors in patients with metastatic clear cell renal cell cancer in the targeted era. The discovery data set from The Cancer Genome Atlas included 19 African American patients, and the authors validated their findings in a data set of 135 patients with 10 African Americans. Then they looked at the National Cancer Database and found that in the targeted era, African-Americans have shorter survival than Caucasians,” said formal discussant Guru Sonpavde, MD, of the University of Alabama at Birmingham.

Unanswered Questions

Dr. Sonpavde continued: “These findings—based on a small number of African American patients—raise several questions. Should we be using therapies other than VEGF inhibitors in African Americans? Will these differences persist in a multivariate analysis controlling for stage, grade, and necrosis? What about mixed-race patients? Should they be studied in a separate group?”

He also questioned whether VHL mutations and VEGF-pathway expression are a valid predictive biomarker, since they are not clearly associated with differentials in outcomes of patients treated with ­VEGFR tyrosine kinase inhibitors and bevacizumab (Avastin).

“Can race or ethnicity—and by extension, germline molecular factors—serve as a predictive factor for treatment benefit or toxicities? Molecular differences between races exhibiting different outcomes using similar agents might inform development of a biomarker across all races,” he said.

In conclusion, Dr. Sonpavde said that further study is needed based on a larger number of African Americans and focused more on molecular panels predictive for benefit from specific agents, which will help develop precision medicine across all populations. ■

Disclosure: Dr. Sonpavde reported no potential conflicts of interest.