Granulomatous mastitis: A diagnostic challenge-3 year single institutional experience

Area of Science:

• Pathology
• Cytopathology
• Oncology

Background:

• Granulomatous mastitis (GM) is frequently misdiagnosed as breast malignancy.
• Differential diagnoses for GM include tuberculosis, infections, and autoimmune diseases.

Purpose of the Study:

• To evaluate the spectrum of granulomatous mastitis on fine-needle aspiration biopsy (FNAB) smears.
• To correlate FNAB findings with histopathological and clinico-radiological data.

Main Methods:

• Retrospective analysis of 22 GM cases diagnosed via FNAB over three years.
• Review of FNAB smears and histopathological sections for granulomas, necrosis, and inflammatory cells.
• Grading of inflammatory cells and multinucleated giant cells.

Main Results:

• Lymphocytes were the most common inflammatory infiltrate, followed by neutrophils and eosinophils.
• Caseous necrosis was observed in 31.8% of cases, with 22.7% diagnosed as tubercular mastitis on FNAB.
• Histopathological correlation in 63.6% of cases revealed idiopathic GM as the most common diagnosis.

Conclusions:

• FNAB is a reliable tool for diagnosing tubercular mastitis and idiopathic GM.
• FNAB helps rule out breast malignancy, preventing unnecessary biopsies for granulomatous breast lesions.