What is the appropriate workup for a 22-year-old male with a painful lump under the left nipple, also known as a subareolar (under the areola) mass, persisting for several weeks?

From the Guidelines

For a 22-year-old male with a painful lump under the left nipple for a few weeks, the initial workup should focus on a thorough history and physical examination to assess for gynecomastia or other underlying conditions, with imaging studies such as breast ultrasound or mammography considered only if suspicious features are present, as recommended by the American College of Radiology 1. The most likely diagnosis is gynecomastia, which requires a focused evaluation. Begin with a thorough history, asking about medication use (including anabolic steroids, marijuana, and prescription drugs like spironolactone), recent weight changes, and family history of breast cancer. Some key points to consider in the history and physical examination include:

• Medication use: Ask about the use of medications that can cause gynecomastia, such as anabolic steroids, marijuana, and prescription drugs like spironolactone.
• Recent weight changes: Assess for any recent weight changes, as these can be associated with gynecomastia.
• Family history of breast cancer: Ask about any family history of breast cancer, as this can increase the risk of breast cancer in men.
• Physical examination: Assess the size, consistency, tenderness, and exact location of the breast tissue, noting any skin changes or nipple discharge. Laboratory tests should include liver function tests, hormone levels (testosterone, estradiol, luteinizing hormone, follicle-stimulating hormone), and thyroid function tests to identify underlying hormonal imbalances. Imaging studies are typically not necessary for young men with classic presentations of gynecomastia, but if the lump is unilateral, hard, fixed, or associated with skin changes, a breast ultrasound should be performed to rule out malignancy, as recommended by the American College of Radiology 1. In cases with suspicious features or family history of breast cancer, a mammogram may be considered, followed by fine-needle aspiration or core biopsy if abnormalities are detected, although the most recent evidence suggests that mammography may not be the first-line imaging modality for men under 25 years of age 1. This workup helps distinguish between benign gynecomastia, which often resolves spontaneously within two years, and more concerning conditions that require specific treatment.

From the Research

Initial Evaluation

• A thorough clinical breast examination is necessary to evaluate the palpable breast mass [ 2 ].
• The clinical history should establish how long the lump has been noted, whether any change has been observed, and whether there is a history of biopsy or breast cancer [ 3 ].
• Risk factors for breast cancer should be noted, but their presence or absence should not influence the decision to investigate a lump further [ 3 ].

Imaging Studies

• Mammography may not be as sensitive in men younger than 40 years, but it can still be used to screen for occult malignancy in the same and contralateral breast [ 2 ].
• Ultrasonography can detect cystic masses and may be used to guide biopsy techniques [ 2 ].
• Ultrasonography is an indispensable tool in breast imaging and can confidently characterize benign cysts and benign and malignant solid masses [ 4 ].

Tissue Sampling

• Fine-needle aspiration is fast, inexpensive, and accurate, and it can differentiate solid and cystic masses [ 2 ].
• Core-needle biopsy allows histologic diagnosis, hormone-receptor testing, and differentiation between in situ and invasive disease [ 2 ].
• Core biopsy, either clinically or image-guided, can usually establish or exclude malignancy, thus reducing the need for surgical biopsy [ 3 ].

Follow-up

• The work-up should be completed expeditiously and the patient kept fully informed throughout [ 3 ].
• Even when malignancy is not found, it may be prudent, in some cases, to arrange follow-up surveillance [ 3 ].