INTRODUCTION: Tuberculosis, particularly its extrapulmonary forms, may mimic malignancy, causing diagnostic uncertainty and treatment delays. This study evaluated clinical, radiological, histopathological, and microbiological features of patients initially assessed for suspected malignancy but subsequently diagnosed with tuberculosis.
METHODS: This retrospective study included patients who underwent biopsy for suspected malignancy between 2019 and 2022, showed granulomatous inflammation histopathologically, and had confirmed tuberculosis. Demographic, clinical, radiological, biopsy, histopathological, and microbiological data were recorded, and comparisons were made by history of malignancy, TB-PCR status, and granuloma type. Tuberculosis was diagnosed based on histopathological, microbiological, and/or compatible clinical findings.
RESULTS: Among 104 patients, the median age was 54 years (IQR, 41–65), and 77 (74.0%) were female. The most common complaint was palpable swelling (29.8%), while 38 (36.5%) were asymptomatic. Tru-cut (42.3%) and excisional (25.0%) biopsies were most frequent, and the breast (19.2%) and cervical and axillary lymph nodes (8.7% each) were the most common sites. Histopathology showed granulomatous inflammation in 49 (47.1%), caseating in 45 (43.3%), and non-caseating in 10 (9.6%). TB-PCR was positive in 23/44 (52.3%), tissue culture in 12/48 (25.0%), body fluid AFB smear in 3/22 (13.6%), and sputum AFB smear in 2/35 (5.7%). Patients with prior malignancy were significantly older (p<0.001), with no differences in microbiological or histopathological findings.
DISCUSSION AND CONCLUSION: Extrapulmonary tuberculosis may closely mimic malignancy, particularly in breast and lymph node lesions. Histopathology remains the diagnostic cornerstone, while microbiological tests show limited sensitivity. Tuberculosis should be considered in the differential diagnosis of granulomatous lesions detected during malignancy work-up.
Keywords: Tuberculosis, Extrapulmonary Tuberculosis, Granulomatous Inflammation