Hematopathology is a branch of pathology that study of hematopoietic cells . Hematopathology may be a board certified subspecialty (American Board of Pathology) practiced by those physicians who have completed general pathology residency (anatomic, clinical, or combined) and extra fellowship training in medical specialty. Hematopoietic cells originate from the bone marrow and contribute the cellular parts of blood as well as red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (megakaryocyte-derived bodies). Leukocytes contribute considerably to the cellular composition of body fluid nodes, the spleen, the thymus, and tissue layer associated with humor tissues, and area to some extent of all the tissues discussed here. Diseases of the organic process system typically manifest as decreases (anemia) or will increase (lymphoma/leukemia) in these cell varieties. Consequently, hematopathologists most often measure peripheral blood smears, bone marrow aspirates and biopsies, and body fluid nodes biopsies to work out the character of organic process illness. The hematopathologists incorporates earliest research with subsidiary techniques as well as general laboratory values, , flow cytometry, and molecular diagnostic tests to determine the exact diagnosis. The hematopathologist works closely with the hematologist/oncologist specialty doctor who sees the patient and decides on the simplest treatment primarily based upon the designation created by the hematopathologist. Diseases of the organic process system area unit myriad and embody hereditary and inherent disorders still as non-inheritable disorders. Hereditary and inherent disorders embody, in part, bone marrow failure syndromes and first deficiency syndromes. Non-inheritable disorders could also be associated with biological process deficiencies (such as iron, folate, and B12 deficient anemia), infectious processes or growth disorders (cancers). Diagnostic criteria and classification pointers for the growth diseases area unit written within the WHO Classification of Tumours of the organic process and lymphatic tissue, last revised in 2008. The growth diseases of organic process cells represent 2 broad classes, myeloid neoplasms and humour neoplasms. Histiocytic and nerve fibre cell neoplasms area unit thought-about on an individual basis. Each class contains many recognized diagnostic entities leading to nearly one hundred differing kinds of organic process cancer, every with process morphology, pathobiology, treatment, and/or prognostic options. Correct classification, still as identification of extra factors which will influence prognosis or response to therapy, is important to permit optimum treatment by the hematologist/oncologist. The hematopathologists accountable for additional studies performed once initiation of medical aid to watch for continuing remission or illness relapse.