Acute lymphoblastic leukemia, FAB classification L1, bone marrow aspirate. The appearance of these blasts very fine nuclear chromatin, nucleoli, and the high nuclear to cytoplasmic ratio is characteristic of this diagnosis.


Acute lymphoblastic leukemia, FAB classification L2, peripheral blood. Five blasts surround a lymphocyte.These blasts are somewhat large and have a varied morphology. They can sometimes be confused with myeloid or monocytic cells.


Philadelphia chromosome-positive acute lymphoblastic leukemia. These blasts have a relatively high nuclear-cytoplasmic ratio and moderately condensed chromatin. They were CD19, CD10, and TdT positive.In this morphology “glossary” are found examples of many of the items discussed in the body of this book. This collection was originally assembled for the Interamerican Division Regional Update in Leukemia course in Puebla, Mexico (Dr. G. Ruiz-Argüelles and Dr. E. Torré-Lopez). It has subsequently been used in Ankara, Turkey (Dr. E. Kansu) and Cordoba, Argentina (Dr. C. Ponzinibbio). Developments in informatics have enabled the costeffective reproduction of these images.The glossary has been rearranged and enlarged since its ASH Education Program introduction last year principally with slides used in the Morphology Panel of the ISH Amsterdam congress last July (Drs. Bain, Brunning, Castoldi, Kluin, Matutes, McArthur, den Ottolander, and Verhoef). It is now divided into lymphoid and myeloid sections. An erythroid section and a miscellaneous section will be added in the future.Unless otherwise stated, oil magnification of Wright-stained smears are shown.


Acute lymphoblastic leukemia, FAB classification L3, bone marrow aspirate. The variation in size and shape of the cells and their nuclei, as well as the presence of cytoplasmic and nuclear vacuoles are characteristic of this diagnosis.


Acute lymphoblastic leukemia, FAB classification L2, bone marrow aspirate, periodic acid-Schiff stain (PAS). The coarse granularity in the cytoplasm as well as some frank cytoplasmic globules are characteristic of the PAS reaction when it is positive in lymphoblasts.


Acute T cell leukemia lymphoma (ATLL). Peripheral blood film from a 38-year-old black Caribbean patient. The lymphocytes are small to medium size and display a highly irregular nucleus with an inconspicuous nucleolus and multiple indentations, resembling the petals of flowers (for this reason they are often designated “flower cells”). Immunophenotype showed the mature, activated helper T cell nature of the cells (TdT-, CD1a-, CD2+, CD3+, CD5+, CD7-) with a CD4+, CD8-, CD25+ phenotype. Antibodies to the human T-cell leukemia/lymphoma virus (HTLV-1) were detected in the patient’s serum, and molecular analysis of the tumor cells showed a clonal integration of the proviral HTLV-1 in the cells’ DNA.

Anaplastic large cell lymphoma. Lymph node and tumor biopsy. A 10-year-old boy presented with a large intra-osseous tumor in the proximal tibia and enlargement of a supraclavicular lymph node. Aspiration cytology of the lymph node (R) showed medium-sized “plasmacytoid” cells with eccentric nuclei. Some cells showed cytoplasmic extensions simulating sarcoma. One cell in the slide shows a small “nuclear window.” A trephine biopsy of the tumor of the tibia (L; H&E) showed a tumor rich in histiocytes. Tumor cells were vimentin, CD30, ALK-1 positive, and weakly CD45RO positive. This is a typical example of a peripheral T cell lymphoma, according to the REAL classification, anaplastic large cell lymphoma (ALCL), (lymphohistiocytic) variant. The ALK-1 positivity suggests a variant translocation t(2;5) since the staining was mainly cytoplasmic (not shown). Tumor cells can be relatively small in this variant of ALCL and may resemble large plasma cells. Bone involvement is relatively common in ALCL.


Anaplastic (Ki-1+) T cell lymphoma, bone marrow smear from an adult patient. The cells are very large, up to ten times the size of a normal lymphocyte and have a nucleus with reticular chromatin and basophilic vacuolated cytoplasm. Immunophenotyping demonstrated the T-cell nature of the cells (CD3+) with expression of CD30 (Ki-1). Most anaplastic Ki-1+ lymphomas are of T-cell origin, characteristically express the Ki-1 antigen and are associated to the t(2;5). BM involvement in anaplastic large cell lymphoma is rare and the presence of these large cells in the bone marrow aspirates is even less frequent. Differential diagnosis includes Hodgkin’s disease and non-hemopoietic tumors. Histology and immunological markers are key tests for the diagnosis.


Lymphoplasmacytic lymphoma associated with IgM monoclonal gammopathy, bone marrow biopsy. The marrow is extensively replaced by small lymphocytes, plasmacytoid lymphocytes, and plasma cells. The process is interpreted as marrow involvement by a plasmacytoid tumor.



IgA myeloma, bone marrow biopsy. Several of the plasma cells contain intranuclear inclusions referred to a Dutcher bodies. These structures are found in a wide spectrum of immunoproliferative disorders and had been most frequently associated with plasmcytoid lymphomas. They lack specificity for any subtype of the immunoproliferative processes.


Amyloid, bone marrow biopsy, H&E stain. A small blood vessel is heavily infiltrated with the pink-staining, waxy amyloid material.


Prolymphocytic leukemia (PLL). This composite slide shows prolymphocytic leukemia (PLL). On the left is B cell PLL and on the right, T cell PLL. BPLL cells correspond to the classic description of Galton et al. (Br J Haematol 27:7, 1974): They are larger than CLL lymphocytes, have condensed chromatin, and have prominent large nucleoli. T-PLL cells have a less conspicuous nucleolus, an irregular nuclear outline, and cytoplasmic blebs, as described by Matutes et al. (Blood 78:12, 1991). In many cases it may be difficult to distinguish B-PLL from T-PLL cells on morphologic grounds alone, without performing additional immunophenotypic studies.