Survival Benefit of Chemotherapy for Metastatic Prostate Cancer Differs by Race

Chemotherapy for metastatic prostate cancer may not offer the same survival benefit across different race/ethnicity groups, according to findings published in The Prostate.

“Caucasian and Asian de novo metastatic prostate cancer patients exhibit the greatest overall survival benefit from chemotherapy exposure,” researchers reported. “Conversely, no overall survival benefit from chemotherapy exposure could be identified in either African-Americans or Hispanic/Latinos.”

The study focused on 4232 US patients with de novo metastatic prostate cancer in the Surveillance, Epidemiology, and End Results (SEER) database in 2014 and 2015. Researchers looked at overall survival differences with and without chemotherapy by race/ethnicity. Among the studied patients, 2690 were Caucasian, 783 were African-American, 504 were Hispanic/Latino, and 257 were Asian.

At 2.5 years of follow-up, overall survival rates in Caucasian patients were 61.5% with chemotherapy and 53.2% without chemotherapy. In Asian patients, survival rates with chemotherapy were 77.7% with chemotherapy compared with 65.0% without chemotherapy.

Meanwhile, survival rate differences appeared less substantial among African-American and Hispanic/Latino patients: 55.2% with chemotherapy compared with 51.6% without chemotherapy in African-Americans, and 62.8% with chemotherapy compared with 57.0% without chemotherapy in Hispanic/Latinos.

“Virtually the same findings were recorded after propensity score matching within each race/ethnicity group,” researchers added.

Proportions and numbers of patients in race/ethnicity groups other than Caucasian with metastatic prostate cancer are small, the authors noted, which makes it difficult to investigate differences specific to race/ethnicity. Nevertheless, the study identified statistically significant lower overall mortality in both the Caucasian and Asian subgroups, the latter of which had fewest patients in the study.

“Since we observed significant improved overall survival in the largest and smallest race/ethnicity subgroup, lack of improved overall survival in the second and third subgroup is unlikely related to sample size limitations,” they advised.

Reference:
Hoeh B, Würnschimmel C, Flammia RS, et al. Effect of chemotherapy in metastatic prostate cancer according to race/ethnicity groups. Prostate. 2022;82(6):676-686. doi:10.1002/pros.24312