Case number:	152
Age:	33
Clinical presentation:	Premenopausal woman with average risk of developing breast cancer presented with a right breast lump with severe pain and tenderness first noticed 2 weeks ago.

Mammography:

Breast composition:	ACR category c (the breasts are heterogeneously dense, which may obscure small masses)
Mammography features:

‣ Location of the lesion:	Right breast, upper outer quadrant at 10–12 o’clock, anterior and middle thirds
‣ Mass:
• Number:	0
• Size:	None
• Shape:	None
• Margins:	None
• Density:	None
‣ Calcifications:
• Typically benign:	None
• Suspicious:	None
• Distribution:	None
‣ Architectural distortion:	Present
‣ Asymmetry:	Present, involving the right upper outer quadrant with prominent glandular tissue
‣ Intramammary node:	None
‣ Skin lesion:	None
‣ Solitary dilated duct:	None
‣ Associated features:	None

Breast composition:	ACR category c (the breasts are heterogeneously dense, which may obscure small masses)
Mammography features:

‣ Location of the lesion:	Follow-up 6 months later after lumpectomy: Right breast, upper outer quadrant at 10–12 o’clock, anterior and middle thirds
‣ Mass:
• Number:	Multiple
• Size:	Largest 1.4 cm in greatest dimension
• Shape:	Oval
• Margins:	Indistinct
• Density:	Equal
‣ Calcifications:
• Typically benign:	None
• Suspicious:	None
• Distribution:	None
‣ Architectural distortion:	Present
‣ Asymmetry:	Present
‣ Intramammary node:	None
‣ Skin lesion:	None
‣ Solitary dilated duct:	None
‣ Associated features:	Surgical scar skin retraction, skin thickening, and trabecular thickening

Ultrasound:

Ultrasound features: Right breast, upper outer quadrant at 9–10 o’clock, 2.5 cm from the nipple and at 1.8 cm skin depth

‣ Mass
• Location:	Right breast, upper outer quadrant at 9–10 o’clock, 2.5 cm from the nipple and at 1.8 cm skin depth
• Number:	1
• Size:	3.2 × 1.5 cm
• Shape:	Irregular
• Orientation:	Not parallel
• Margins:	Indistinct
• Echo pattern:	Heteroechoic
• Posterior features:	No posterior features
‣ Calcifications:	None
‣ Associated features:	Vascularity: vessels in rim
‣ Special cases:	None

Ultrasound features: Right breast, upper outer quadrant at 9–10 o’clock, 2.5 cm from the nipple and at 1.8 cm skin depth

‣ Mass
• Location:	Right breast, upper outer quadrant at 9–10 o’clock, 2.5 cm from the nipple and at 1.8 cm skin depth
• Number:	Multiple
• Size:	1.2 cm in greatest dimension
• Shape:	Irregular
• Orientation:	Not parallel
• Margins:	Indistinct
• Echo pattern:	Heteroechoic
• Posterior features:	No posterior features
‣ Calcifications:	None
‣ Associated features:	Skin thickening and discharging sinus
‣ Special cases:	None

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:	Upper outer
• Localization technique:	Palpation
• Nature of aspirate:	Scant whitish purulent material
‣ Cytological description:	Smears reveal many neutrophils admixed with lymphocytes, histiocytes, and plasma cells. Many histiocytes have an epithelioid appearance. Many multinucleated giant cells are also noted
‣ Reporting category:	Benign
‣ Diagnosis:	Granulomatous mastitis
‣ Comments:	None

Histopathology:

Excision of lump in breast

Histopathology features:

‣ Specimen type:	Excision of lump in breast
‣ Laterality:	Right
‣ Macroscopy:	Single fibrofatty tissue bit (4.0 × 3.0 × 1.5 cm). Cut section firm and whitish
‣ Histological type:	Sections reveal breast tissue showing aggregates of lymphoplasmacytoid cells and abscesses replacing and infiltrating the ducts. Granulomas composed of epithelioid cells, lymphocytes, and multinucleated giant cells are present. Some of these granulomas shows necrosis and neutrophilic infiltration. Ziehl–Neelsen stain for acid-fast bacteria negative. Routine bacterial culture and culture for mycobacteria were negative. PCR test for Mycobacterium tuberculosis was negative. Impression: Granulomatous mastitis with acute inflammation
‣ Histological grade:
‣ Mitosis:
‣ Maximum invasive tumour size:
‣ Lymph node status:
‣ Peritumoural lymphovascular invasion:
‣ DCIS/EIC:
‣ Margins:
‣ Pathological stage:
‣ Biomarkers:
‣ Comments:

Case summary:

Premenopausal woman presented with a right breast lump with severe pain and tenderness. Diagnosed as BI-RADS 2 on imaging and as granulomatous mastitis on cytology and histopathology.

Learning points:

Mastitis with progression of inflammation leads to abscess formation. The abscess is hypoechoic or heteroechoic with irregular margins and the necrotic liquefied material forms a track to drain the contents from a sinus opening as is seen in this case. Chronic recurrent abscesses may be caused by granulomatous mastitis inflammatory changes.