Black/white breast cancer subtype incidence in men differs from trends in women

December 12, 2019

Incidence rates for hormone receptor positive (HR+) breast cancers are considerably higher in black men than white men, in stark contrast to lower incidence rates of those cancer subtypes in black versus white women. That's according to a new American Cancer Society study that used nationwide data to provide the first report on differences in subtype-specific breast cancer incidence rates between black men and white men. The study appears in JNCI Cancer Spectrum.

Incidence rates of breast cancer in men are higher in blacks than in whites in the United States, in contrast to rates for women, among whom breast cancer incidence rates remain slightly higher in whites than in blacks. There are considerable racial differences in breast cancer rates by subtype in women, with black women having about twice the rate of triple-negative breast cancer and lower rates of HR-positive cancers. This difference has significant implications for patient outcomes.

However, it is unknown whether similar subtype-specific differences in breast cancer incidence rates occur between black men and white men. To find out, researchers led by Hyuna Sung, Ph.D. examined subtype specific breast cancer incidence rates in black and white men in the U.S. using a contemporary nationwide database.

They found that rates for all subtypes were higher among black than white men, with rates for HR+/HER- breast cancers about 41% higher among black men compared to white men; about 65% higher for HR+/HER2+, more than 2.5 times higher for HR-/HER2+, and 2.27 times higher for triple-negative breast cancer. Conversely, among women, rates in blacks were 21% lower for HR+/HER2- and comparable for HR+/HER2+, but 29% and 93% higher for HR-/HER2+ and triple-negative subtypes, respectively.

"Reasons for the elevated risk of breast cancer in black men are largely unknown but may involve multitude of risk factors including genetic and non-genetic factors," write the authors. Racial differences in the prevalence of mammography and menopausal hormone supplements are thought to have contributed to the historically higher incidence rate of HR+ cancers in white women, but these are not factors in breast cancer in men.

Well-known risk factors for male breast cancer include family history of breast and/or ovarian cancers, pathogenic mutations in BRCA2, radiation exposure, and conditions that alter hormonal balance such as Klinefelter syndrome and gynecomastia, and potentially obesity and diabetes. Moreover, previous studies have found higher level of estradiol was found to be associated with increased risk of male breast cancer after controlling for body mass index, suggesting a presence of estrogen-mediated carcinogenesis in male breast cancer. However, whether associations of these risk factors vary by tumor subtypes remains unknown and should be considered in future etiologic studies.

The authors conclude that black-white patterns in subtype-specific breast cancer incidence rates differ between men and women, especially for HR+ disease, and that this may have implications for the etiology of breast cancer. Future studies, they write, should identify factors contributing to these patterns to further inform prevention strategies.
Article: Subtype-specific breast cancer Incidence rates in black versus white men in the United States; Hung et al., JNCI Cancer Spectrum, doi: 10.1093/jncics/pkz091

URL upon publication:

American Cancer Society

Related Breast Cancer Articles from Brightsurf:

Oncotarget: IGF2 expression in breast cancer tumors and in breast cancer cells
The Oncotarget authors propose that methylation of DVDMR represents a novel epigenetic biomarker that determines the levels of IGF2 protein expression in breast cancer.

Breast cancer: AI predicts which pre-malignant breast lesions will progress to advanced cancer
New research at Case Western Reserve University in Cleveland, Ohio, could help better determine which patients diagnosed with the pre-malignant breast cancer commonly as stage 0 are likely to progress to invasive breast cancer and therefore might benefit from additional therapy over and above surgery alone.

Partial breast irradiation effective treatment option for low-risk breast cancer
Partial breast irradiation produces similar long-term survival rates and risk for recurrence compared with whole breast irradiation for many women with low-risk, early stage breast cancer, according to new clinical data from a national clinical trial involving researchers from The Ohio State University Comprehensive Cancer Center - Arthur G.

Breast screening linked to 60 per cent lower risk of breast cancer death in first 10 years
Women who take part in breast screening have a significantly greater benefit from treatments than those who are not screened, according to a study of more than 50,000 women.

More clues revealed in link between normal breast changes and invasive breast cancer
A research team, led by investigators from Georgetown Lombardi Comprehensive Cancer Center, details how a natural and dramatic process -- changes in mammary glands to accommodate breastfeeding -- uses a molecular process believed to contribute to survival of pre-malignant breast cells.

Breast tissue tumor suppressor PTEN: A potential Achilles heel for breast cancer cells
A highly collaborative team of researchers at the Medical University of South Carolina and Ohio State University report in Nature Communications that they have identified a novel pathway for connective tissue PTEN in breast cancer cell response to radiotherapy.

Computers equal radiologists in assessing breast density and associated breast cancer risk
Automated breast-density evaluation was just as accurate in predicting women's risk of breast cancer, found and not found by mammography, as subjective evaluation done by radiologists, in a study led by researchers at UC San Francisco and Mayo Clinic.

Blood test can effectively rule out breast cancer, regardless of breast density
A new study published in PLOS ONE demonstrates that Videssa® Breast, a multi-protein biomarker blood test for breast cancer, is unaffected by breast density and can reliably rule out breast cancer in women with both dense and non-dense breast tissue.

Study shows influence of surgeons on likelihood of removal of healthy breast after breast cancer dia
Attending surgeons can have a strong influence on whether a patient undergoes contralateral prophylactic mastectomy after a diagnosis of breast cancer, according to a study published by JAMA Surgery.

Young breast cancer patients undergoing breast conserving surgery see improved prognosis
A new analysis indicates that breast cancer prognoses have improved over time in young women treated with breast conserving surgery.

Read More: Breast Cancer News and Breast Cancer Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to