Blood levels of 2 proteins can predict prostate cancer-specific death in African-American patients, according to research presented at the 2021 AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved.
Researchers found that levels of pleiotrophin (PTN) and tumor necrosis factor receptor superfamily member 9 (TNFRSF9) in the blood at diagnosis could predict cancer-specific mortality with 78.2% accuracy in African-American patients.
“One of the major challenges in clinical oncology today is differentiating men who have lethal forms of prostate cancer from those that have a more slow-growing disease,” said Tsion Zewdu Minas, PhD, of the National Cancer Institute in Bethesda, Maryland, when presenting this research at the conference.
Dr Minas and colleagues had set out to identify predictors of lethal disease in 819 patients with prostate cancer, 394 of whom were African American and 425 of whom were European American.
The researchers measured 82 immune-oncological proteins in the patients’ blood at diagnosis. The team also looked at 6 clinical or demographic variables — education, age, body mass index, diabetes, regular aspirin use, and smoking history — as potential predictors of lethal prostate cancer.
The median follow-up was 8.6 years from diagnosis. During this time, 57 patients died of prostate cancer, and 202 patients died of all causes.
The researchers found a “robust” predictive signature of lethal prostate cancer for African-American patients but not for European-American patients, Dr Minas said.
Among African Americans, the top predictors were 2 proteins, TNFRSF9 and PTN, and regular aspirin use. The proteins were positively associated with the risk of prostate cancer-specific death, and aspirin use was negatively associated with the risk of lethal prostate cancer.
The 2 proteins predicted prostate cancer-specific mortality with 78.2% accuracy. When PTN, TNFRSF9, and aspirin use were combined, the accuracy increased to 83.7%.
The probability of prostate cancer-specific survival was significantly lower in patients with elevated levels of both TNFRSF9 and PTN at diagnosis than in patients with low levels of either or both proteins (adjusted hazard ratio, 5.75; P <.0001).
These results suggest that blood levels of PTN and TNFRSF9 could be used for risk stratification of African-American patients at the time of diagnosis, Dr Minas said. However, she noted, this work needs to be validated in other cohorts to determine if these biomarkers can be used in the clinic.
Minas TZ, Candia J, Dorsey TH, et al. Blood levels of TNFRSF9 and PTN predict lethal prostate cancer among African American men. Presented at: AACR 2021 Virtual Cancer Health Disparities; October 6-8, 2021. Abstract PR-11.
This article originally appeared on Cancer Therapy Advisor