What are the treatment options for breast cysts?

Breast Cyst Treatment

Treatment of breast cysts depends entirely on cyst type: simple cysts require no intervention unless symptomatic, complicated cysts can be observed or aspirated, and complex cysts must undergo tissue biopsy due to malignancy risk of 14-23%. 1

Classification-Based Treatment Algorithm

Simple Cysts (BI-RADS 2)

• No treatment is necessary if the cyst meets all ultrasound criteria (anechoic, well-circumscribed, round/oval with imperceptible wall and posterior enhancement) and clinical findings are concordant. 1, 2
• Therapeutic aspiration may be performed only if the patient has persistent clinical symptoms (pain, discomfort). 1, 2
• If aspiration is performed and clear fluid is obtained with complete mass resolution, the patient can return to routine screening mammography. 1, 3
• Cytologic examination of aspirated fluid is required only if bloody fluid is obtained. 1

Complicated Cysts (BI-RADS 3)

These cysts contain low-level echoes or debris but lack solid components, thick walls, or thick septa, with malignancy risk <2%. 1

Two management options exist:

• Option 1 (Observation): Short-term follow-up with physical examination and ultrasound ± mammography every 6-12 months for 1-2 years to assess stability. 1, 2
• Option 2 (Aspiration): This should be more strongly considered in patients likely to be lost to follow-up. 1

Critical decision points after aspiration:

• If clear fluid is obtained and the cyst resolves: Follow-up at 4-6 weeks to confirm no recurrence, then routine screening. 3
• If bloody fluid is obtained: Place a tissue marker, send fluid for cytologic evaluation, and follow based on cytology results. 1
• If the cyst increases in size during observation: Proceed immediately to tissue biopsy. 1, 2
• If a mass persists after aspiration: Biopsy is required. 1
• If the cyst recurs after initial successful aspiration: Tissue biopsy is recommended. 1

Complex Cysts

These have discrete solid components including thick walls, thick septa, or intracystic masses. 1

• Tissue biopsy is mandatory due to malignancy risk of 14-23%. 1, 4
• Ultrasound-guided core needle biopsy is preferred over fine needle aspiration for superior sensitivity and specificity. 2, 5
• Aspiration alone is insufficient and should not be performed as definitive management. 4

Technical Considerations for Aspiration

When aspiration is indicated, the procedure is straightforward:

• Use a 21- or 22-gauge needle for simple technique with minimal complications. 3
• The procedure is cost-effective, minimally invasive, and can be performed in the office setting. 6, 3
• Complications (local discomfort, bruising, infection) are uncommon. 3

Follow-Up After Negative Workup

• For cysts that resolve after aspiration with clear fluid: Re-evaluate in 4-6 weeks; if no recurrence, return to routine screening. 3
• For complicated cysts managed conservatively: Physical examination with ultrasound every 6-12 months for 1-2 years. 1, 2
• If stable after 1-2 years of surveillance: Return to routine screening mammography. 2

Common Pitfalls to Avoid

• Do not routinely send clear cyst fluid for cytology—this is unnecessary and increases costs without clinical benefit. 1, 7
• Do not perform aspiration on complex cysts as a diagnostic or therapeutic maneuver; these require tissue diagnosis. 4
• Do not assume all palpable masses are cysts—physical examination has only 61% positive predictive value for cysts. 6
• Do not fail to follow up aspirated cysts—recurrence or persistence mandates tissue diagnosis. 1
• Aspiration should be strongly considered over observation in patients with poor follow-up reliability to prevent loss to surveillance. 1