The Cytology, Distribution and Function of the Neoplastic Cells in Leukaemic Reticuloendotheliosis

198

The clinical and pathologic findings in 21 patients with hairy cell leukemia (leukemic reticuloendotheliosis) are reviewed. The disease predominantly involved males, and was characterized by a chronic course with an insidious onset and marked splenomegaly. A hypersplenic syndrome with pancytopenia, “hairy cells” in the peripheral blood, and frequent “dry taps” on bone marrow aspiration were common features. Only one patient in this series was leukemic at the onset of disease. Pathologically, the changes in the spleen were distinct from those in other leukemias and malignant lymphomas, and consisted of a diffuse heavy infiltration of the red pulp cords and engorgement of the sinuses by a uniform population of mononuclear cells without mitoses. These cells were not identifiable as either monocytes or lymphocytes, although the pattern of infiltration was more consistent with histiocytic or monocytic than with lymphocytic proliferation. Infiltrates of similar cells were found in the bone marrow, lymph nodes, and livers of many patients early in the course of the disease. Despite this diffuse organ involvement, only 4 patients in this series died, and long survival was common. Splenectomy appeared to be the treatment of choice, whereas vigorous chemotherapy was contraindicated. Accurate diagnosis by recognition of the histologic criteria is therefore essential.

Hairy cell leukemia (leukemic reticuloendotheliosis).I. A clinical pathologic study of 21 patients

Burke

Byrne

Rappaport

1974

198

Hairy cell leukemia:Enzyme histochemical characterization, with special reference to splenic stromal changes

Nanba

Jaffe

Soban

et al. 1977

Seven spleens and two peripheral blood specimens from eight patients with hairy cell leukemia were examined with enzyme cytochemical and histochemical methods. Hairy cells consistently exhibited acid phosphatase and tartrate-resistant acid phosphatase. However, nonspecific esterases characteristic of monocytes and histiocytes were consistently absent or very weak. beta-glucuronidase and cytoplasmic membrane-bound ATPase were positive in four cases, suggesting a possible relationship to the B-lymphocytic series. Fundamental splenic changes were accumulation of hairy cells and benign macrophages within the pulp cords, with resulting extreme expansion of the cords. Abnormally well developed ellipsoids were identified around the sheathed arteries within the cords. Sinuses, specifically delineated with the NASDA reaction, were atrophic and often destroyed. No cytogeneologic relationship was found between sinus endothelial cells and hairy cells. The pulp cords are the primary site of involvement of the spleen in hairy cell leukemia. A simultaneous proliferation of neoplastic cells, histiocytes and reticulum fibers accounts for the splenomegaly and clinical hypersplenism characteristic of the disease.

Structural and functional properties of the „hairy” cells of leukemic reticuloendotheliosis

Braylan

Jaffe

Triche

et al. 1978

Structural and functional studies were performed on "hairy" cells from 7 patients with leukemic reticuloendotheliosis ("hairy cell leukemia") (HCL). In all cases tartrate-resistant acid phosphatase-containing cells were demonstrated. The abnormal cells displayed complement receptors in 6 cases although there was variation in the number of abnormal cells expressing the receptor. Receptors for IgG were present in all 7 cases on a high number of abnormal cells. In 6 cases the "hairy" cells showed surface immunoglobulins (SIg) when examined immediately after isolation. Procedures to eliminate m uiuo bound protein substantially decreased the number of SIg-bearing cells, indicating that most SIg represented cytophilic protein. In 2 cases, however, SIg restricted to a single light chain type remained on the abnormal cells, suggesting that in these 2 cases the SIg may have been an intrinsic cellular product. Attempts to demonstrate immunoglobulin synthesis were unsuccessful and there was no evidence that the "hairy" cells contained cytoplasmic immunoglobulin. In uitro phago-cytosis of latex particles by the abnormal cells was observed in all cases by transmission electron microscopy although the number of phagocytic "hairy" cells varied widely from case to case. In 4 of 5 spleens with HCL, normal macrophages detected by the presence of nonspecific esterase were abundant and markedly enlarged. The electronic size distribution of HCL suspensions demonstrated a characteristic double-peaked curve and modal volumes seldom seen in other chronic leukemias or lymphomas. Quantitative scanning electrotl microscopic analysis of HCL populations corroborated that the peculiar "hairy" appearance of the abnormal cells was due to extensive surface ruffles which are not observed in normal or neoplastic lymphocytes. Our findings suggest that the "hairy" cells are structurally and functionally unique elements , different than any other normal or abnormal cell of the lymphoreticular system known at present. Studies of cellular DNA quantitation and thymidine incorporation indicated that the growth rate of the "hairy" cells is exceedingly low. Cancer 41210-227, 1978. EUKEMIC RETICULOENDOTHELIOSIS ("HAIRY ease represents a well-defined clinicopathologic L cell leukemia") (HCL) is an uncommon entity and is readily distinguishable from other type of chronic leukemia which has recently re-types of chronic lymphoid or myeloid prolifera-ceived a great deal of attention.