Bone Marrow Profile in Haematological Disorders with reference to Flow Cytometry and RT-PCR in Acute Leukaemia

Introduction: Evaluation of non neoplastic and neoplastic haematological disorders require bone marrow examination which is an important diagnostic tool. This includes Bone Marrow Aspiration (BMA) and Bone Marrow Biopsy (BMB). Subtyping of Acute Leukaemia (AL) requires flow cytometry immunophenotyping and Real Time Polymerase Chain Reaction (RT-PCR), which helps in identifying cell antigens and genetic abnormalities, respectively. This is helpful to guide specific treatment for patients. Aim: To evaluate the clinical profile, cytological and histological pattern of various haematological disorders using bone marrow examination and to determine immunophenotypes using ancillary techniques in patients with AL. Materials and Methods: This was a cross-sectional observational study conducted in Department of Pathology, Sree Mookambika Institute of Medical Sciences, Kulasekharam, Tamil Nadu, India. Data was collected for a period of two years from May 2020 to April 2022. A total of 62 cases were included. Clinical details and bone marrow examination findings were noted for all BMA and BMB cases that satisfied the inclusion criteria and flow cytometry along with RT-PCR diagnosis was done for suspected AL cases. Analysis was done using Statistical Package for the Social Sciences (SPSS) version 20.0. Results: Among the 62 cases studied, age of patients ranged from 32 to 81 years. Majority of them were in the 5th to 6th decade. Females 32 (51.6%) were more commonly affected. Pancytopenia 15 (24.2%) was the most common clinical presentation. Total 49 (79%) were diagnosed with BMA and 61 (98.4%) were diagnosed with BMB. Megaloblastic anaemia 16 (25.8%) and acute myeloid leukaemias 6 (9.6%) were the most common cause of benign haematological disorder and haematological malignancy respectively. The RT-PCR test for Break point Cluster-Abelson Tyrosine Kinase (BCR-ABL) and Promyelocytic Leukaemia-Retinoic Acid Receptor Alpha (PML- RARA) fusion gene analysis showed association in patients with Acute Lymphoblastic Leukaemia (ALL) and Acute Myeloid Leukaemia (AML) respectively. Conclusion: Biopsy, being gold standard, provides details about the pattern, extent of tumour, metastatic deposit and granulomatous pathology, but BMA also proved better for study of the cell. Flow cytometry and RT-PCR were effective tools that enable the identification of immunophenotype in AL as well as to assess treatment progress and predict prognosis