In a male patient with a 0.7 × 0.8 cm anechoic focus inferior to a hypo‑echoic breast lesion on ultrasound and no gynecomastia, what is the appropriate next step in management?

Management of Anechoic Focus Inferior to Hypoechoic Breast Lesion in Male Patient Without Gynecomastia

Proceed with ultrasound-guided core needle biopsy of the hypoechoic lesion, as this represents a suspicious solid mass in a male breast that requires tissue diagnosis to exclude malignancy. 1, 2

Rationale for Immediate Tissue Diagnosis

The presence of a hypoechoic lesion in a male patient without clinical gynecomastia is concerning and cannot be assumed benign. Male breast cancer typically presents as a palpable mass or imaging-detected abnormality, and the absence of gynecomastia does not reduce suspicion for malignancy. 1 In fact, approximately 50% of men with breast cancer may have coexisting gynecomastia, but the converse—absence of gynecomastia—should heighten concern when a discrete mass is present. 1

The 0.7 × 0.8 cm anechoic focus likely represents a simple cyst (which is benign), but the adjacent hypoechoic lesion is the primary concern requiring evaluation. 1, 2

Diagnostic Algorithm

Step 1: Complete Ultrasound Characterization

• Evaluate the hypoechoic lesion for suspicious features: irregular margins, internal vascularity on color Doppler, posterior acoustic shadowing, or heterogeneous echotexture. 1, 2
• Confirm the anechoic focus meets criteria for a simple cyst: anechoic, round/oval, circumscribed margins, posterior acoustic enhancement, no internal echoes or vascularity. 1
• If the anechoic focus is truly a simple cyst, it requires no further evaluation. 1

Step 2: Obtain Diagnostic Mammography

• Male patients with a solid breast mass should undergo diagnostic mammography to evaluate for additional lesions, assess the extent of disease, and identify features suggestive of malignancy (irregular mass, architectural distortion, suspicious microcalcifications). 1
• Mammography in males can distinguish between gynecomastia patterns (nodular, dendritic, or diffuse glandular) and discrete masses concerning for cancer. 1

Step 3: Perform Image-Guided Core Needle Biopsy

• Ultrasound-guided core needle biopsy is the preferred method for tissue diagnosis of the hypoechoic lesion, providing superior sensitivity, specificity, and histological grading compared to fine-needle aspiration. 1, 2
• Core biopsy allows for evaluation of hormone receptor status (ER, PR) and HER2 if malignancy is identified, which is critical for treatment planning. 2
• Place a marker clip at the biopsy site to facilitate surgical localization if malignancy is confirmed. 2, 3

Step 4: Ensure Imaging-Pathology Concordance

• After biopsy, verify that pathology results are concordant with imaging findings. 1, 2
• If benign pathology is discordant with suspicious imaging features (e.g., irregular margins, vascularity), surgical excision is mandatory. 1, 2
• If pathology shows indeterminate lesions (atypical hyperplasia, papillary lesions, radial scars with atypia), surgical excision is required. 1, 4

Critical Pitfalls to Avoid

• Do not assume the hypoechoic lesion is benign based solely on the patient's age or absence of gynecomastia. Male breast cancer occurs at a median age of 63 years but can present at any age, and frequently presents at an advanced stage. 1
• Do not rely on short-interval follow-up for a discrete solid mass in a male patient. Unlike in female patients where probably benign masses (BI-RADS 3) may be followed, the rarity of benign solid masses in males and the high stakes of delayed cancer diagnosis warrant immediate tissue diagnosis. 1
• Do not perform fine-needle aspiration instead of core biopsy. Core biopsy provides superior diagnostic accuracy and allows for receptor testing if cancer is identified. 1, 2
• Do not ignore the hypoechoic lesion while focusing on the anechoic focus. The anechoic focus is likely a benign simple cyst, whereas the hypoechoic lesion represents the true concern. 1, 2

If Malignancy is Confirmed

• Refer immediately for surgical consultation and staging workup according to breast cancer treatment guidelines. 1, 2
• Male breast cancer is often hormone receptor-positive, making receptor status essential for systemic therapy planning. 2
• Assess for axillary lymph node involvement with sentinel lymph node biopsy if invasive carcinoma is identified. 2

If Benign Pathology is Confirmed and Concordant

• Clinical follow-up at 6-12 months with physical examination is appropriate for concordant benign findings. 1, 2
• If the lesion remains stable, return to routine surveillance (though routine screening mammography is not standard for males without specific risk factors). 1
• Any interval increase in size or development of suspicious features mandates repeat biopsy. 1, 2