What are the distinguishing features of a worrisome breast mass in men versus gynecomastia (Gynecomastia)?

From the Guidelines

Worrisome breast masses in men differ significantly from gynecomastia, with concerning features including hard consistency, fixed position, eccentric location, unilateral presentation, associated skin changes, nipple discharge, axillary lymphadenopathy, and rapid growth, warranting prompt evaluation with imaging and possibly biopsy. The key differences between worrisome breast masses and gynecomastia are:

• Consistency: Worrisome masses are hard, while gynecomastia is typically soft and mobile
• Location: Worrisome masses are often eccentric, while gynecomastia is centered beneath the nipple-areolar complex
• Bilaterality: Gynecomastia is often bilateral, while worrisome masses are more likely to be unilateral
• Skin changes: Worrisome masses may have associated skin changes, such as dimpling, ulceration, or nipple retraction, which are lacking in gynecomastia
• Nipple discharge: Worrisome masses may have nipple discharge, especially bloody discharge, which is uncommon in gynecomastia
• Age: Breast cancer risk increases with age, particularly after 60 years, making it more likely in older men 1

The timing and pattern of development also differ between worrisome breast masses and gynecomastia. Gynecomastia often develops gradually in response to hormonal changes, medications, or underlying conditions, while malignant masses typically show progressive growth without regression. Any concerning features in a male breast mass warrant prompt evaluation with imaging, such as mammography or ultrasound, and possibly biopsy, as male breast cancer tends to be diagnosed at more advanced stages due to delayed recognition 1.

Some key points to consider when evaluating a male breast mass include:

• Clinical findings consistent with gynecomastia or pseudogynecomastia do not typically require imaging 1
• Ultrasound may not be routinely indicated in men with clinical findings consistent with gynecomastia or pseudogynecomastia, but can be useful in evaluating indeterminate breast masses 1
• Mammography is highly sensitive and specific in distinguishing benign from malignant disease and is likely more sensitive than US at detecting breast cancer 1
• A bilateral mammogram is routinely performed in symptomatic males to assess for symmetry and detect asymptomatic contralateral gynecomastia or nonpalpable contralateral carcinoma 1

From the Research

Features of Worrisome Breast Mass in Men vs Gynecomastia

• A worrisome breast mass in men is often characterized by a discrete mass at mammography or ultrasonography (US) 2
• The relationship of the mass to the nipple should be carefully assessed, with an eccentric location being highly suspicious for cancer 2
• Secondary signs that may indicate malignancy include nipple retraction, skin ulceration or thickening, increased breast trabeculation, and axillary adenopathy 2
• Gynecomastia, on the other hand, has a typical appearance on mammography and is the most common cause of male breast enlargement 3, 4
• Gynecomastia is often characterized by a symmetrical, disc-shaped density centered behind the nipple-areolar complex 4

Differentiation between Benign and Malignant Masses

• Differentiation between benign and malignant masses is critical to alleviate patient anxiety and avoid unnecessary procedures 2
• Mammography is the initial imaging modality of choice, with ultrasonography used when a mass is detected or suspected 5, 6
• Fine-needle aspiration cytology (FNAC) and biopsy may be necessary in cases where imaging findings are suspicious or inconclusive 3, 4
• However, in cases with a classical appearance of gynecomastia on mammography, supplemental ultrasound, FNAC, or biopsy may be superfluous and contribute to unnecessary costs 4

Clinical Evaluation

• A male patient with a palpable unilateral breast mass consistent with gynecomastia on the basis of historical, physical, and mammographic findings does not require surgical biopsy unless other clinical indications prevail 3
• Lack of symptoms (pain) related to the mass is probably not helpful in deciphering gynecomastia from breast cancer 3
• Clinical information, such as a history of medical conditions or use of medications known to cause gynecomastia, should be taken into account when evaluating a male breast mass 3