Editorial: Advances in Diagnosis of Hematological Disorders

Abstract

Over the last two decades, the advances in diagnostic techniques have greatly enabled to dissect the various hematological disorders, especially in the field of hemato-oncology into various subtypes based upon the various characteristics of cell surface antigens, glycoproteins, intracytoplasmic antigens which can be easily identified by flow cytometric studies. Identification of various mutations by various cytogenetic studies starting from conventional cytogenetics, FISH ,qualitative and quantitative PCR studies have provided the correct diagnosis, prediction of prognosis and monitoring of therapy. These techniques have helped in identifying the minimal residual disease. In solid tumors, use of immunohistochemistry is commonly used for characterization and typing of various malignancies in addition to cytogenetics and molecular studies. Immunohistochemistry technique is simple, cost effective and enables the pathologist for correct diagnosis and currently being used in all centers. Development of techniques such as micro array is an additional tool for better characterization, subtyping of various disorders etc. Presently, various blood disorders are classified not only on morphological features alone but by multiple parameters based upon on natural course of the disease, prognostic factors, molecular diagnostic techniques and therapeutic responses. Various international classifications have been used for classification such as French American & British (FAB) , World Health Organization (WHO) etc. These classifications are being reviewed and updated periodically to enable the clinicians for correct diagnosis, and to plan the current therapies to improve the long term survivals. In the present symposium the use of flow cytometry in various hematological disorders [1] along with utility of FNAC, lymphnode biopsy, immunohistochemistry and molecular diagnosis in pediatric lymphomas [2] and present status of childhood myelodysplatic syndrome [3] have been reviewed and each manuscript provides the state of art information. Flowcytometry provides the characteristics of any subtype single cells such as red cells, white cells & platelets. The cells of the interest are labelled with fluorescently conjugated moncolonal antibiodies. The flurochrome gets activated as these cells pass through a laser beam. The emitted flurorescene is measured in two scatters; forward and side scatter [4]. Using the above principals flowcytometry has helped to provide definitive diagnosis of various red cells, white cells and platelet disorders. Flowcytometric studies have not only helped in sub classification of Glanzmann’s thrombocytopenia into three subtypes but have helped in carrier detection also. Immunophenotyping has become standard for diagnosis, predicting the prognosis and helping in planning the treatment of leukemia and lymphoma. At some centers it is also being used to monitor the minimal residual disease (MRD) with the help of aberrant leukemia associated immunophenotype. Expression of CD 56 along with high expressions of CD-34 are predictors of poor prognosis in acute myeloid leukemia (AML), while in acute promyelocytic leukemia expression of CD-2 and CD-56 and presence of short PML-RARA transcript are poor prognostic factors. Other molecular techniques which are being employed for further characterization of leukemia include mutation analysis by ARMS-PCR ,PCR and restriction analysis, PCR and sequencing. All these techniques are currently being used at leading centers in the country for accurate diagnosis and for monitoring of therapy. Diagnosis of lymphoma starts from the clinical suspicion to fine needle aspiration cytology and ending with molecular diagnosis. The advent of targeted therapy has improved the five year survival in lymphomas of childhood to 70–80 %, only when V. P. Choudhry (*) Sunflag Pahuja Centre for Blood Disorders, Sunflag Hospital, Sector 16 A, Faridabad, Haryana 121002, India e-mail: vedpchoudhry@yahoo.co.in