Case number:	070
Age:	45
Clinical presentation:	Premenopausal woman with average risk of developing breast cancer presented with a lump in the left breast. On examination, she had a freely mobile lump in the upper inner quadrant of the left breast.

Mammography:

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

‣ Location of the lesion:	Left breast, upper inner quadrant at 11 o’clock, middle third
‣ Mass:
• Number:	1
• Size:	Not measurable, obscured by the glandular parenchyma
• Shape:	Irregular
• Margins:	Indistinct
• Density:	Equal
‣ Calcifications:
• Typically benign:	None
• Suspicious:	None
• Distribution:	None
‣ Architectural distortion:	Present
‣ Asymmetry:	Focal
‣ Intramammary node:	None
‣ Skin lesion:	None
‣ Solitary dilated duct:	None
‣ Associated features:	Architectural distortion

Ultrasound:

Ultrasound features: Left breast, upper inner quadrant at 10–11 o’clock

‣ Mass
• Location:	Left breast, upper inner quadrant at 10–11 o’clock
• Number:	3
• Size:	Three hypoechoic lesions, taller than wider, with irregular margins in upper inner quadrant: Lesion 1: 2.2 × 1.6 cm in upper inner quadrant at 11 o’clock position, 7.0–8.0 cm from the nipple Lesion 2: 1.2 × 0.9 cm in inner quadrant at 10–11 o’clock position, 3.0 cm from the nipple Lesion 3: 0.4 cm lesion adjacent to lesion 2, at 10 o’clock position, 4.0 cm from the nipple
• Shape:	Irregular
• Orientation:	Not parallel
• Margins:	Angular
• Echo pattern:	Hypoechoic
• Posterior features:	No posterior features
‣ Calcifications:	None
‣ Associated features:	Duct changes and internal vascularity
‣ Special cases:	None

BI-RADS:

BI-RADS Category: 5 (highly suggestive of malignancy)

Further assessment:

Further assessment advised: Referral for cytology

Cytology:

Cytology features:

‣ Type of sample:	FNAC (solid lesion)
‣ Site of biopsy:
• Laterality:	Left
• Quadrant:	Upper inner
• Localization technique:	Palpation
• Nature of aspirate:	Whitish
‣ Cytological description:	Smear shows loosely cohesive clusters of malignant cells. The cells have marked nuclear pleomorphism, prominent nucleoli, and irregular nuclear membranes. Many lymphocytes are seen in the background
‣ Reporting category:	Malignant
‣ Diagnosis:	Carcinoma – high grade
‣ Comments:	None

Histopathology:

MRM

Histopathology features:

‣ Specimen type:	MRM
‣ Laterality:	Left
‣ Macroscopy:	On serial sectioning, a greyish white, friable, soft necrotic tumour (2.8 × 2.1 × 2.0 cm) is identified located in the upper inner quadrant, 2.0 cm from the skin, which is flush with the base. The tumour was 1.0 cm from the medial surgical resection margin. Another firm greyish white area (1.4 × 1.0 × 1.0 cm) is seen 3.0 cm inferior and lateral to the first tumour. It is 2.8 cm from the skin and 1.0 cm from the base.
‣ Histological type:	Invasive carcinoma of no special type
‣ Histological grade:	Grade 3 (3 + 3 + 2 = 8)
‣ Mitosis:	14
‣ Maximum invasive tumour size:	Largest 2.8 cm in greatest dimension (another smaller of 1.4 cm)
‣ Lymph node status:	0/24
‣ Peritumoural lymphovascular invasion:	Not identified
‣ DCIS/EIC:	Not identified
‣ Margins:	Free of tumour
‣ Pathological stage:	pT2(2)N0
‣ Biomarkers:
‣ Comments:	Tumour also shows extensive necrosis and areas of lymphocytic infiltration. Adjacent breast shows fibrocystic changes. A few areas with ADH and sclerosing adenosis also seen

Case summary:

Premenopausal woman presented with lump in the left breast. Diagnosed as left breast carcinoma (multifocal), BI-RADS 5 on imaging, as high-grade breast carcinoma on cytology, and as invasive breast carcinoma of no special type, pT2(2)N0 on histopathology.

Learning points:

The differential diagnoses of multiple breast masses are:

benign lesions, all benign or with a breast cancer;
multiple foci of breast cancer;
multiple papillomas;
lobular carcinoma;
systemic diseases involving the breast, such as lymphoma, granulomatous infections, or melanoma;
metastasis to breast from distant primary, such as ovarian, lung, soft tissue, gastrointestinal, pancreas, or neuroendocrine tumours; and
breast cancer with intramammary metastatic node.

Correlating imaging findings with clinical presentation and pathological findings helps in confirming the nature of the lesions.