Breast cancer-specific mortality risk in men with hormone receptor–positive breast cancer persists for at least 20 years, but patterns of breast cancer–specific mortality (BCSM) are distinct from those in women, a new study finds.
Previous studies in women with hormone receptor–positive (HR+) breast cancer have shown a risk of distant recurrence and death for at least 20 years after diagnosis, but data for men are limited, wrote Julieta Leone, MD, of the Dana Farber Cancer Institute, Boston, and colleagues.
What is Known About Hormone Receptor–Positive Breast Cancer Mortality in Men vs. Women?
Invasive breast cancer in men is rare and consequently understudied, the researchers wrote. Previous studies of BCSM in men with more than 5 years’ follow-up consist mainly of case series at single institutions, the researchers wrote in JAMA Oncology (2024 Feb 29. doi: 10.1001/jamaoncol.2023.7194 ).
“We believed it would be important to study this issue to help inform the management of men with breast cancer,” corresponding author, José P. Leone, MD, said in an interview.
In 2021, Dr. J.P. Leone and colleagues published a study in Breast Cancer Research and Treatment that examined the 20-year risk of BCSM in women that included more than 36,000 individuals who had survived for 5 years, with a median of 14 years’ follow-up.
In that study of women , the BCSM risk at 20 years was significantly higher for those with HR-negative tumors, but the risk was still elevated for both types. Patients with stage IIIC HR-positive disease had four times the risk of BCSM over 20 years and those with stage IIIC HR-negative disease had seven times the risk of BCSM over 20 years compared with the risk of death not related to breast cancer, the researchers wrote.
Another study of nearly 2,400 men with breast cancer (mainly HR+) by Dr. J.P. Leone and colleagues showed that cancer stage, tumor subtype, and race were associated with overall survival and breast cancer-specific survival.
What Does the New Study Add?
The current study included 2,836 men diagnosed with stage I to stage III HR+ breast cancer between 1990 and 2008, using data from the Surveillance, Epidemiology, and End Results (SEER) database.
“We found that in men with breast cancer, the risk of breast cancer mortality persists for at least 20 years and that [the risk] depends on traditional clinicopathologic factors, such as age, tumor size, nodal status and tumor grade,” Dr. J.P. Leone said in an interview.
“The prolonged risk [of breast-cancer specific mortality] over 20 years that we observed in our study is similar to that previously reported in women; however, the kinetics of the risk over the 20-year period appears different in men,” he emphasized.
The men in the study, especially those with a higher stage of disease, appeared to have a bimodal distribution of the BRCA mortality risk, he said.
Two peaks were identified, he explained; an early peak in mortality risk at approximately 4 years from diagnosis and another at approximately 11 years after diagnosis.
Although women with breast cancer had a prolonged risk of breast cancer mortality, “the kinetics of the risk does not include 2 peaks, even in women with higher stage of disease.” In women with higher stage breast cancer, the peak mortality risk occurs approximately 5 years after diagnosis, he said.