RESUMO
Background: Lymphoblastic lymphoma (LBL) accounts for about 2% of all lymphomas. Recognition of T/B-LBL albeit of their rareness is very important as they present as localized diseases with low tumor burden. They can present both at nodal and extranodal sites. Limitation of diagnosis and classification of lymphoma on fine needle aspirate (FNA) can be minimized by clubbing it with flowcytometric immunophenotyping (FCI) to ensure diagnostic accuracy rapidly. Aim: Study of a series of 18 cases of LBL to assess the utility of FCI on FNA and effusion samples in extramedullary LBL. Methods and Material: FCI was done on FNA and effusion samples from 130 morphologically diagnosed/suspicious cases of lymphoreticular malignancy, followed by peripheral blood and bone marrow (BM) examination. The patients diagnosed to have B/T LBL, based on WHO 2017 classification, were selected for further analyses. Results: FCI of 130 cases showed 91 mature and 18 precursor lymphoid neoplasms. These 18 cases were from lymph nodes (11), pleural fluid (03), and soft tissue masses (04). Peripheral blood and BM of 15/18 cases were normal of which FCI revealed T-LBL (11) and B-LBL (04). Two cases (both T LBL) showed BM involvement (<25%), while one case of B-LBL which was misdiagnosed as mature lymphoma by immunohistochemistry (IHC) evolved as B ALL. Conclusions: Diagnosis of extramedullary B/T-LBL needs comprehensive evaluation of clinical presentation, cytomorphology, and immunophenotyping. Rapid and accurate diagnosis by FCI on FNA and effusion samples allows early therapeutic decisions, thereby avoiding leukemic dissemination.
RESUMO
OBJECTIVE: To assess the performance of fine needle aspiration cytology (FNAC) in the diagnosis of tuberculosis mastitis. MATERIALS AND METHODS: Diagnostic test performance evaluation using two methods-as compared to an alloyed gold standard as well as in the absence of a gold standard. Alloyed gold standard combined the results of acid fast bacilli in cytology smears, histopathological confirmation, and response to treatment. Bayesian estimation of test parameters was done in the absence of the gold standard. RESULTS: FNAC was carried out in 6,496 consecutive cases of breast lump and 104 cases of granulomatous mastitis were detected. Both methods of test parameter estimation identified a high specificity of FNAC for the diagnosis of tuberculosis mastitis (98.9% and 98.4%, respectively). Estimation of sensitivity was falsely high (100%) using the alloyed gold standard because of a workup bias and falsely low (8.41%) using the Bayesian estimation because of low prevalence. Likelihood ratios by both methods suggested that FNAC has good discriminatory capability. CONCLUSION: In situations where prevalence of tuberculosis is high and where facilities for histopathological evaluation do not exist, FNAC can offer an optional alternative to base the therapeutic decision for starting antitubercular treatment.
