Males with breast cancer are 19 per cent more likely to die than females across all disease stages, according to a study in JAMA Oncology.

Dr. Xiao-Ou Shu, Vanderbilt University Medical Center. CREDIT: Vanderbilt University Medical Center.

Additional research is required to determine the lower survival rate, but researchers hypothesize it could be due to less effective treatment, patient lifestyle, or distinct cancer biology.

Senior author Xiao-Ou Shu, MD, Ph.D., MPH says additional analysis would require international assistance due to a lack of research in the area.

Data suggests male breast cancer accounts for less than 1 per cent of all cases.

“It is so rare, it would be extremely difficult for any single institute to recruit a sufficient number of patients for research,” Shu said in a statement.

Shu’s team analyzed 11 years of data from Jan. 1, 2004, to Dec. 31, 2014, including 1.8 million female patients and 16,025 male patients.

“The bottom line is that we need more studies specifically focused on male breast cancer,” Shu said.

FDA calls for greater inclusion of male patients in breast cancer trials

In August, the U.S. Food and Drug Administration (FDA) issued draft guidance calling for greater inclusion of men in clinical breast cancer trials.

Historically, male participation has either been excluded or limited in breast cancer research — making it difficult to predict long-and-short term outcomes.

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While some FDA-approved treatments are gender-neutral in their indication, several therapies are only approved for women, Richard Pazdur, M.D., director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, said in a statement.

“As breast cancer in men is rare, they have typically not been included in clinical trials for breast cancer treatment,” Dr. Pazdur added.

“This has led to a lack of data, so their treatment is generally based upon studies and data collected in women.”