Case number:	110
Age:	60
Clinical presentation:	Postmenopausal woman with average risk of developing breast cancer presented with a lump in the right axilla. Examination revealed normal breasts with axillary lymphadenopathy.

Mammography:

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

‣ Location of the lesion:	Right breast, axillary lymphadenopathy
‣ Mass:
• Number:	3
• Size:	Largest 2.0 × 1.6 cm
• Shape:	None
• Margins:	None
• Density:	None
‣ Calcifications:
• Typically benign:	Typically benign, round
• 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 axillary

‣ Mass
• Location:	Right axillary
• Number:	Multiple
• Size:	Largest 2.0 × 1.6 cm
• Shape:	None
• Orientation:	None
• Margins:	None
• Echo pattern:	None
• Posterior features:	No posterior features
‣ Calcifications:	None
‣ Associated features:	None
‣ Special cases:	None

BI-RADS:

BI-RADS Category: 4A (low level of suspicion for malignancy)

Further assessment:

Further assessment advised: Referral for cytology

Cytology:

Cytology features:

‣ Type of sample:	FNAC
‣ Site of biopsy:
• Laterality:	Right
• Quadrant:	Axillary nodule
• Localization technique:	Ultrasound-guided FNAC
• Nature of aspirate:	Whitish
‣ Cytological description:	Epithelioid cell conglomerates with many lymphocytes
‣ Reporting category:	Benign
‣ Diagnosis:	Granulomatous lymphadenitis
‣ Comments:	None

Histopathology:

Axillary lymph node

Histopathology features:

‣ Specimen type:	Axillary lymph node
‣ Laterality:	Right
‣ Macroscopy:	Lymph node (3.5 × 3.5 × 2.0 cm)
‣ Histological type:	Section shows granulomatous inflammation with caseous necrosis, suggestive of tuberculous lymphadenitis
‣ Histological grade:
‣ Mitosis:
‣ Maximum invasive tumour size:
‣ Lymph node status:
‣ Peritumoural lymphovascular invasion:
‣ DCIS/EIC:
‣ Margins:
‣ Pathological stage:
‣ Biomarkers:
‣ Comments:

Case summary:

Postmenopausal woman presented with painful lump in right axilla diagnosed as right axillary reactive lymphadenopathy, BI-RADS 4A on imaging, as granulomatous lymphadenitis on cytology, and as tuberculous lymphadenitis on histopathology.

Learning points:

Suspicious unilateral axillary lymphadenopathy in the absence of abnormalities in the breast are categorized as BI-RADS 4. Additional morphological details and correlated systemic findings further group them as BI-RADS 4A, 4B, or 4C.
Isolated axillary nodal tuberculosis in the absence of pulmonary and extrathoracic tuberculosis is very rare, even in endemic areas, it may be secondary to either bloodstream dissemination or direct extension from an adjacent tuberculous process. Grossly, it can present as a lump or as multiple sinuses and may be mistaken clinically for nodal metastasis from advanced breast carcinoma.