January 28, 2021
Cardiovascular disease and related risk factors can be common among male breast cancer patients, suggests a small study in this rare malignancy.
Tachyarrhythmia existed in 8% of the men before cancer treatment and developed in 13% during treatment.
Two patients had pre-existing heart failure, two patients developed the disease after treatment, and another two patients experienced a decline in left ventricular ejection fraction during the course of their cancer treatment.
"Our hope is that treating male breast cancer patients becomes a multidisciplinary approach where oncologists recruit their cardio-oncologist counterparts to mitigate cardiovascular risk factors, so patients live a long and healthy life after cancer treatment," said Michael Ibrahim, one of the study authors and a fourth-year medical student at Georgetown University in Washington, DC.
The data were presented January 25 as part of the American College of Cardiology's Advancing the Cardiovascular Care of the Oncology Patient virtual course, which is hosting live sessions February 5-6.
Although the association between cardiovascular disease and breast cancer is well documented in female breast cancer patients, there is little evidence in their male counterparts, especially African Americans, he noted.
To provide some context, Ibrahim highlighted a 2018 report in nearly 3500 female breast cancer patients, ages 40 to 79, in whom 52% were obese/overweight, 35% had hypertension, and 28% hyperlipidemia.
Diabetes was present in 7.5% of the women, which was roughly equivalent to the 8% found among the men, he said. The men were of similar age (38 to 79 years), with 42% being African American, 29% white, 4% Hispanic, and 25% another ethnicity.
Importantly, half of the men had a family history of breast cancer, and two were positive for a mutation in the BRCA gene.
A 2017 in-depth review of male breast cancer cites advancing age, hormonal imbalance, radiation exposure, and family history of breast cancer as key risk factors for the development of the disease, but that the "most relevant risk factor" is a mutation in the BRCA2 gene.
Male breast cancer accounts for less than 1% of all breast cancers, but the incidence is rising and in some patient groups reaching 15% over their lifetimes, the paper notes. Additionally, these patients are at special risk for developing a second cancer.
Remarkably, 25% of men in the DC cohort were diagnosed with a second primary malignancy, 13% a third primary cancer, and 4% a fourth primary cancer, Ibrahim reported. "This goes to show that male breast cancer patients should routinely undergo cancer screening."
The initial diagnosis was invasive ductal carcinoma in 79% of the men, with the remaining ductal carcinoma in situ. All patients underwent mastectomy, 17% had anthracycline chemotherapy, 8% received HER2-targeted therapy, 16% had radiation, and 71% hormone therapy.
In terms of cardiovascular management, statins were the most prescribed medication (46%), followed by antiplatelet therapy (42%), and angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers (38%).
An implantable cardioverter defibrillator/pacemaker was the most common intervention (16%), followed by bypass surgery in 8% and coronary angioplasty in 4%.
Ibrahim noted that the study was limited by the small sample size and that further research is needed to understand the risk of pre-existing cardiovascular disease on long-term outcomes as well as the cardiotoxic effects of chemo-radiation in male breast cancer patients.
In a statement, Ibrahim reiterated the need for a multidisciplinary cancer care team to evaluate patients' cardiovascular risk prior to and through cancer treatment.
"On a more personal level, cancer patients are already surprised by their cancer diagnosis," he added. "Similar to the pretreatment consultation with radiation oncology, breast surgery, and medical oncology, an upfront cardiovascular risk assessment provides greater comfort and further minimizes psychological surprise with cardiovascular complications going into cancer treatment."
The authors have disclosed no relevant financial relationships.