Male Breast Cancer Management

Epidemiology and Risk Factors

• The average age of diagnosis for male breast cancer is 67 years, which is approximately 5 years older than for women, with incidence rates rising steadily with age 1
• Male breast cancer typically affects older men, with no peak incidence at age 40 1
• Key risk factors for male breast cancer include black ethnicity 2, radiation exposure to chest 2, genetic predisposition (BRCA2, BRCA1, CHEK2, PALB2 mutations) 2, and conditions associated with hyperestrogenism (e.g., Klinefelter's syndrome) 1

Hormonal Dependence and Receptor Status

• Male breast cancer is predominantly hormone receptor-positive, making endocrine therapy highly effective in treatment 1

Treatment Approach

• Tamoxifen is the standard adjuvant therapy for hormone receptor-positive male breast cancer 1, 2
• Men with hormone receptor-positive breast cancer should be offered tamoxifen for an initial duration of five years 1, 3
• Men who have completed five years of tamoxifen and have a high risk of recurrence may be offered an additional five years of tamoxifen therapy 1, 3
• Aromatase inhibitors alone are less effective in men and should be combined with a gonadotropin-releasing hormone agonist/antagonist if used due to tamoxifen contraindication 1

Advanced or Metastatic Disease

• Men with advanced or metastatic, hormone receptor-positive, HER2-negative breast cancer should be offered endocrine therapy as first-line therapy, except in cases of visceral crisis or rapidly progressive disease 3
• Options for endocrine therapy include tamoxifen, an aromatase inhibitor with a gonadotropin-releasing hormone agent, and fulvestrant 3
• Cyclin-dependent kinase 4/6 inhibitors can be used in men as they are used in women 3

Special Considerations

• Testosterone/androgen supplementation should not be used by men with breast cancer 3
• Genetic counseling and germline genetic testing of cancer predisposition genes should be offered to all men with breast cancer 1

Surveillance

• Ipsilateral annual mammogram should be offered to men with a history of breast cancer treated with lumpectomy 3
• Contralateral annual mammogram may be offered to men with a history of breast cancer and a genetic predisposing mutation 1
• Breast magnetic resonance imaging is not recommended routinely 1

Male Breast Cancer Characteristics

Epidemiology and Prevalence

• Male breast cancer accounts for less than 1% of all breast cancers, according to the American College of Radiology 4

Histological Types

• The limited development of lobular elements in the male breast contributes to the rarity of infiltrating lobular carcinoma, as noted by the American College of Radiology 5

Treatment Considerations

• Treatment approaches for male breast cancer, which is predominantly hormone receptor-positive, are similar to those for women but must account for the higher prevalence of hormone receptor positivity in men, as recommended by the American Society of Clinical Oncology [6] [7]

Epidemiology, Risk Factors, and Screening of Male Breast Cancer

Incidence and Epidemiology

• Male breast cancer is exceedingly rare, representing less than 1 % of all breast cancers, while the female incidence in Europe is approximately 94.2 cases per 100 000 women【8】.

Hormonal and Medical Risk Factors (Male‑Specific)

• Hyperestrogenism‑related conditions—including Klinefelter’s syndrome, gynecomastia, and liver cirrhosis—are identified as major risk factors for developing breast cancer in men【8】.

Female‑Specific Risk Factors (Absent in Men)

• In women, endogenous and exogenous estrogen exposure, low parity, and atypical hyperplasia are primary contributors to breast cancer risk【8】.
• Additional lifestyle factors such as a Western‑style diet, obesity, and alcohol consumption also increase female breast cancer incidence【8】.

Screening Recommendations

• No organized screening programs exist for average‑risk men, in contrast to population‑based mammography offered to women aged 50–69 years【8】【9】.

Immediate Referral and Diagnostic Management of a Suspicious Axillary Mass in Male Patients

Imaging Assessment and Biopsy Recommendations

• A 3‑cm hypoechoic axillary mass that appears suspicious on ultrasound is classified as BI‑RADS 4 or 5, which requires tissue biopsy according to NCCN breast cancer guidelines. 10
• Core‑needle biopsy is the preferred method for any lesion categorized as BI‑RADS 4 or 5, providing superior diagnostic accuracy and histologic grading. 10
• In men with clinically suspicious axillary lymph nodes, ultrasound‑guided fine‑needle aspiration or core biopsy should be performed to obtain pathologic confirmation of malignancy. 11, 12

Necessity of Early Specialist Referral

• Immediate referral to a breast surgery specialist or surgical oncologist is recommended; early specialist involvement facilitates coordinated diagnostic work‑up (mammography, biopsy, staging) and ensures comprehensive pathologic assessment including estrogen‑receptor (ER), progesterone‑receptor (PR), and HER2 testing, which are essential for treatment planning. 13, 14
• Male patients with breast cancer benefit from evaluation by an experienced multidisciplinary team that can perform sentinel lymph‑node mapping when indicated, assess for additional disease, and develop a comprehensive treatment plan. 11, 12

Coordinated Diagnostic Work‑up

• Bilateral diagnostic mammography should be ordered promptly as part of the initial evaluation of a male patient with a suspicious axillary mass. 10, 13
• The specialist should coordinate an ultrasound‑guided core‑needle biopsy of the axillary lesion to obtain tissue for histology and biomarker analysis. 10
• After tissue acquisition, the specialist oversees complete staging evaluation, including clinical examination for a primary breast lesion and appropriate imaging studies. 13, 14
• Pathologic confirmation must include immunohistochemical testing for ER, PR, and HER2, guiding adjuvant systemic therapy decisions. 13

Surgical Planning and Staging

• Based on biopsy results and staging, the specialist will determine the need for sentinel lymph‑node biopsy or axillary lymph‑node dissection as part of surgical management. 11, 12

Avoiding Delays in Management

• Referral should not be postponed while awaiting completion of the diagnostic work‑up; the specialist can orchestrate the necessary investigations to ensure optimal tissue handling and accurate pathology. 10, 13
• Prompt specialist involvement is associated with improved treatment planning and outcomes for male breast cancer patients. 10, 13