Case number:	046
Age:	61
Clinical presentation:	Postmenopausal woman with average risk of developing breast cancer presented with a lump in the upper quadrant of the left breast. Examination revealed a lump above the nipple–areolar complex with an inverted nipple on the left side.

Mammography:

Breast composition:	ACR category a (the breasts are almost entirely fatty)
Mammography features:

‣ Location of the lesion:	Left breast, upper outer quadrant at 2 o’clock, middle third
‣ Mass:
• Number:	1
• Size:	3.7 cm in greatest dimension
• Shape:	Irregular
• Margins:	Spiculated
• Density:	High
‣ Calcifications:
• Typically benign:	None
• Suspicious:	None
• Distribution:	None
‣ Architectural distortion:	Present
‣ Asymmetry:	None
‣ Intramammary node:	None
‣ Skin lesion:	None
‣ Solitary dilated duct:	None
‣ Associated features:	Skin retraction, nipple retraction, skin thickening, trabecular thickening, and axillary adenopathy

Breast composition:	ACR category a (the breasts are almost entirely fatty)
Mammography features:

‣ Location of the lesion:	Right breast, all quadrants, entire breast, middle third
‣ Mass:
• Number:	0
• Size:	No
• Shape:	None
• Margins:	None
• Density:	None
‣ Calcifications:
• Typically benign:	Round, rim
• Suspicious:	None
• Distribution:	Diffuse
‣ Architectural distortion:	None
‣ Asymmetry:	None
‣ Intramammary node:	None
‣ Skin lesion:	None
‣ Solitary dilated duct:	None
‣ Associated features:	None

Ultrasound:

Ultrasound features: Left breast, upper outer quadrant at 2 o’clock

‣ Mass
• Location:	Left breast, upper outer quadrant at 2 o’clock
• Number:	1
• Size:	3.8 × 2.7 cm
• Shape:	Irregular
• Orientation:	Not parallel
• Margins:	Angular
• Echo pattern:	Hypoechoic
• Posterior features:	Posterior shadowing
‣ Calcifications:	None
‣ Associated features:	Skin thickening, skin retraction, internal vascularity, and left axillary lymphadenopathy of altered morphology
‣ 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
‣ Site of biopsy:
• Laterality:	Left
• Quadrant:	Upper outer and another nodule in the areola
• Localization technique:	Palpation
• Nature of aspirate:	Whitish
‣ Cytological description:	Smears from both areas reveal malignant cells arranged in sheets or isolated. Individual cells are pleomorphic with high N:C ratio, hyperchromatic nuclei, and prominent nucleoli
‣ Reporting category:	Malignant
‣ Diagnosis:	Carcinoma
‣ Comments:	None

Histopathology:

MRM

Histopathology features:

‣ Specimen type:	MRM
‣ Laterality:	Left
‣ Macroscopy:	MRM specimen of left breast (28.0 × 20.0 × 7.0 cm) covered by a flap of skin (16.0 × 3.5 cm). Nipple is flattened and areola shows slightly elevated area just below the nipple. Cut surface shows a firm greyish white tumour (3.0 × 1.5 × 3.0 cm) with infiltrating margins seen in the upper outer quadrant. Base is 1.2 cm from the tumour. A second tumour nodule (2.0 × 1.2 × 2.0 cm) is seen below the areola. The rest of the breast is unremarkable
‣ Histological type:	Invasive breast carcinoma of no special type
‣ Histological grade:	Grade 3 (3 + 3 + 2 = 8)
‣ Mitosis:	14
‣ Maximum invasive tumour size:	3.0 cm in greatest dimension
‣ Lymph node status:	9/17
‣ Peritumoural lymphovascular invasion:	Present
‣ DCIS/EIC:	Cribriform DCIS of low grade; EIC absent
‣ Margins:	Sections from nipple and areola are involved by the tumour. Sections from the base and separately sent muscle are free of tumour
‣ Pathological stage:	pT2(2)N2
‣ Biomarkers:
‣ Comments:

Case summary:

Postmenopausal woman presented with left breast lump. Diagnosed as left breast carcinoma with skin thickening and retraction, and left nipple retraction, BI-RADS 5 on imaging, as left breast carcinoma on cytology, and as invasive breast carcinoma of no special type, pT2(2)N2 on histopathology.

Learning points:

Linear opacities indicating tethered ligaments of Cooper are seen from the surface of the mass to the subcutaneous tissues with skin and nipple retraction. Histopathology showed invasion of the reticular dermis by the tumour cells. However, in the absence of skin ulceration or skin nodules, the tumour stage is not T4.
Dimpling of the skin, nipple retraction, or other skin changes, except those in T4b (ulceration, ipsilateral satellite skin nodules, or skin oedema, including peau d’orange) and T4d (inflammatory carcinoma) may occur in T1, T2, or T3 tumours without affecting the TNM classification.