Breast cancer in males accounts for about 1% of all breast cancer cases. Due to its rarity, not much is known about this disease. To help add to the knowledge about this condition, two recent studies, one from the United States and the other from Brazil, were conducted that examined features of the disease, including treatment patterns, prognostic factors, age and stage at time of diagnosis, and histology.

Data from the National Cancer Data Base revealed that a total of 10,873 cases of stages I-III male breast cancer occurred in the U.S. between 2004 to 2014. The median age at the time of diagnosis was 64 years. About 90% of men had estrogen receptor (ER)–positive disease. Triple negative BC occurred in about 6%. Approximately 43% were in stage II at the time of diagnosis. 

Seventy-one percent of men underwent a total mastectomy and 24% had breast-conserving surgery. Thirty-nine percent received some form of adjuvant radiotherapy. Patients who received radiotherapy tended to be younger (i.e., <70 years). Fewer than half (44.5%) received chemotherapy, and 62% of those with ER-positive tumors received endocrine therapy. Approximately 13% received neoadjuvant chemotherapy.

Gene-expression tests were ordered in more than one-third of patients (36.5%) with Oncotype DX being the most commonly ordered test (35%). Of these patients, 55% had a recurrence score of <18, 32% had a score of 18-31, and 9% had a score >31. Higher scores indicate greater risk of recurrence. Men with higher Oncotype DX scores were more likely to receive chemotherapy.

During this 10-year study period, the investigators found that there was a significant increase in the rates of mastectomy, endocrine therapy, radiation therapy, and oncogene testing. 

The overall 5-year survival rate was 79.1% with a median overall survival (OS) of 12.1 years and a median survival of 11.5 years for those with stage II and 7.2 years for those with stage III BC. Negative prognostic factors for OS included older age, black race, higher Charleston Comorbidity Index, high tumor grade and stage of disease, and having had a total mastectomy. 

Positive prognostic factors included living in a higher socioeconomic neighborhood, progesterone-receptor positive tumors, and having received chemotherapy, radiation therapy, or endocrine therapy. 

On multivariant analysis, among those with ER-positive BC who were treated with surgery and endocrine therapy, the use of chemotherapy was found to be associated with improved OS in patients with stage II and III BC. Radiation therapy administered after breast-conservation surgery was found to improve OS in all stages of disease. 

The second study from Brazil, which included data on 817 men whose mean age was 60.3 years (vs. 56.2 years in women) found that one-third of patients had stage II disease at the time of diagnosis. Whereas stage 0 was more common in women, men had a higher frequency of stage III and IV disease. Ductal carcinoma occurred in about 90% of both sexes. Men had higher frequencies of rarer types such as papillary or sarcomas.

Both of these studies help paint of picture of the profile of the male patient with breast cancer. Pharmacists should be aware of the special characteristics and features of the disease found in this population in order to be able to better serve their patients.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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