Case number:	129
Age:	51
Clinical presentation:	Perimenopausal woman with average risk of developing breast cancer presented with a lump in the right breast and mastalgia of duration 15 days. Examination revealed a 4 cm lump in the right breast.

Mammography:

Breast composition:	ACR category b (there are scattered areas of fibroglandular density)
Mammography features:

‣ Location of the lesion:	Right breast, upper outer quadrant at 10 o’clock, middle third, 2.0 cm from the nipple and at 1.0 cm skin depth
‣ Mass:
• Number:	Multiple
• Size:	Largest 4.5 × 3.5 cm. This is the clinically palpable lump of concern
• Shape:	Oval
• Margins:	Circumscribed
• Density:	Equal
‣ Calcifications:
• Typically benign:	None
• Suspicious:	None
• Distribution:	None
‣ Architectural distortion:	None
‣ Asymmetry:	None
‣ Intramammary node:	None
‣ Skin lesion:	None
‣ Solitary dilated duct:	None
‣ Associated features:	None

Breast composition:	ACR category b (there are scattered areas of fibroglandular density)
Mammography features:

‣ Location of the lesion:	Left breast, lower inner quadrant at 6–9 o’clock, anterior and middle thirds
‣ Mass:
• Number:	Multiple
• Size:	Largest 0.5 cm
• Shape:	Round
• Margins:	Circumscribed
• Density:	Equal
‣ Calcifications:
• Typically benign:	None
• Suspicious:	None
• Distribution:	None
‣ Architectural distortion:	None
‣ Asymmetry:	None
‣ Intramammary node:	None
‣ Skin lesion:	None
‣ Solitary dilated duct:	None
‣ Associated features:	None

Ultrasound:

Ultrasound features: Right breast, central portion of the breast, multiple cysts in para-areolar region, the largest in the upper outer quadrant at 10 o’clock position, 2.0 cm from the nipple and at 1.0 cm skin depth

‣ Mass
• Location:	Right breast, central portion of the breast, multiple cysts in para-areolar region, the largest in the upper outer quadrant at 10 o’clock position, 2.0 cm from the nipple and at 1.0 cm skin depth
• Number:	Multiple
• Size:	Largest 4.0 × 2.1 cm
• Shape:	Oval
• Orientation:	Parallel
• Margins:	Circumscribed
• Echo pattern:	Anechoic
• Posterior features:	Posterior shadowing
‣ Calcifications:	None
‣ Associated features:	None
‣ Special cases:	Simple cyst

Ultrasound features: Left breast, upper outer quadrant at 10 o'clock, a few subcentimetre-sized cysts are seen in the para-areolar region

‣ Mass
• Location:	Left breast, upper outer quadrant at 10 o'clock, a few subcentimetre-sized cysts are seen in the para-areolar region
• Number:	2 to 3
• Size:	Largest 0.6 cm
• Shape:	Round
• Orientation:	Parallel
• Margins:	Circumscribed
• Echo pattern:	Anechoic
• Posterior features:	No posterior features
‣ Calcifications:	None
‣ Associated features:	None
‣ Special cases:	Simple cyst

BI-RADS:

BI-RADS Category: 2 (benign)

Further assessment:

Further assessment advised: Referral for cytology

Cytology:

Cytology features:

‣ Type of sample:	FNAC
‣ Site of biopsy:
• Laterality:	Right
• Quadrant:
• Localization technique:	Palpation
• Nature of aspirate:	14 mL of yellowish fluid aspirated
‣ Cytological description:	Smears reveal a few benign ductal cell clusters, foamy macrophages, occasional cluster of apocrine cells, against a background of proteinaceous material. Smears from residual lump reveal a few benign fibroadipose fragments
‣ Reporting category:	Benign
‣ Diagnosis:	Fibrocystic lesion, non-proliferative
‣ Comments:	None

Case summary:

Perimenopausal woman presented with a right breast lump and mastalgia. Diagnosed as multiple simple cysts in both breasts, BI-RADS 2 on imaging and as non-proliferative fibrocystic change on cytology.

Learning points:

Masses caused by cystic lesions of the breast are extremely common on mammography and ultrasound. When multiple cysts are present – at least three cysts, with at least one cyst in each breast – a benign BI-RADS 2 assessment is usually appropriate.
The cysts in fibrocystic change can be microscopic or grossly visible of large size. On FNA, the cysts need to be completely drained first and then aspiration should be done from the residual breast nodule.