Androgen deprivation therapy (ADT) may be more risky a prostate cancer treatment approach in African-Americans than in others with this cancer, possibly because this patient population has accompanying conditions that interact poorly with ADT and shorten survival, according to a recent study.
“The use of ADT in African-American men should be reserved for treating higher-risk prostate cancer, for which level-one evidence supports its use,” Dr. Anthony V. D’Amico, a professor of medicine at Harvard Medical School and chief of genitourinary radiation oncology at Brigham and Women’s Hospital and Dana-Farber Cancer Institute, wrote in the study, also reported in a press release.
“However, they [African-Americans] are also more likely to harbor occult high-grade/stage prostate cancer despite low-risk prostate cancer indices, and ADT use is often required to maximize survival,” D’Amico added. “Because of this dilemma, it remains unanswered whether the use of neoadjuvant ADT in favorable-risk prostate cancer to reduce prostate size and facilitate brachytherapy … is helpful or harmful in African American men.”
ADT is an anti hormone therapy used with radiation therapy to treat intermediate- or high-risk prostate cancer. Androgen hormones such as testosterone are required for prostate cancer cells to grow. Reducing the level of testosterone with drugs can prevent cancer growth, but there is no proof that ADT benefits patients with low- or favorable-risk prostate cancer.
For the study, “Race and mortality risk after radiation therapy in men treated with or without androgen-suppression therapy for favorable-risk prostate cancer,” published in Cancer, D’Amico and colleagues analyzed data from more than 7,500 men, ages 62-74, who were treated at the Chicago Prostate Cancer Center between October 1997 and May 2013 for low- or favorable-risk prostate cancer.
All men received radiotherapy, and 1,500 of them also received ADT for four months. About 500 of the patients (7.3%) were of African descent.
Within an eight-year median followup period (time between the end of radiotherapy to either the date of death or final data update), 869 men had died, 48 of them because of prostate cancer and 821 due to other causes.
Researchers found that the risk of all-cause and other-cause mortality was significantly higher among African-American men who received ADT compared people of other ethnic backgrounds who received this treatment, and compared to blacks who were not given ADT.
According to the study’s authors, further research is needed to determine the biological basis for the increase in mortality in African-American men who receive ADT.