Phagocytic myeloma cells in asymptomatic multiple myeloma.

Phagocytic plasmacytoma in a dog

“…Plasma cells normally are not considered to be cells with innate phagocytic capacity; however, phagocytosis by tumors of plasma cell origin is a rare but well-recognized phenomenon reported in the human medical literature. [9][10][11][12][13][14][15][16][17] One study examining the incidence of phagocytosis by plasma cells in human malignant plasma cell disorders found in vivo phagocytic activity in 6 of 401 patients (1.6%). 12 One case of multiple myeloma demonstrating erythrophagocytic activity has been described previously in a dog.…”

“…18 The nature of the phagocytic activity identified in individual clinical cases described in the human medical literature is variable, with erythrophagocytosis being the most commonly documented. [9][10][11][12][13][14][15][16][17][18] In some myelomas phagocytosis of mature erythrocytes, erythrocyte precursors, granulocytes, platelets, and lymphocytes has been described. 12,13 In other tumors phagocytosis of subsets of these cell populations has been shown.…”

“…12,13 In other tumors phagocytosis of subsets of these cell populations has been shown. [10][11][12]14,16,17 Cells of some tumors appear to phagocytose only a single element, either erythrocytes or platelets. 9, 12,13,15,18 In 1 report of multiple myeloma, tumor cells acquired phagocytic capability only in the terminal stages of disease.…”

“…Upon presentation for staging, the serum chemistry profile revealed a mild increase in creatine kinase activity (734 U/L, reference interval 10-320 U/L) and anion gap (26.8, reference interval [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. Results of a CBC included a mild increase in plasma protein concentration (8.2 g/dL, reference interval 6.1-7.5 g/dL) and a moderate, mature neutrophilic leukocytosis with monocytosis (WBC 34.5 3 10 3 /lL, reference interval 6.4-15.8 3 10 3 /lL; segmented neutrophils 29.3 3 10 3 / uL, reference interval 3.4-9.8 3 10 3 /lL; monocytes 2.1 3 10 3 / lL, reference interval 0.2-1.1 3 10 3 /lL).…”

A case of primary plasma cell leukemia exhibiting hemophagocytic plasma cells relapsed with multiple cutaneous plasmacytoma

“…Hemophagocytosis in the bone marrow is a characteristic feature of some aggressive disorders, such as hemophagocytic syndrome by histiocytes, but more rarely by myeloblasts, in acute myeloid leukemia. Furthermore, this characteristic is extremely rare among plasma cells, particularly in PCL, and only a few reports on such cases have been published [ 3 4 5 6 7 8 ]. Herein, we report a rare case of cutaneous infiltration of malignant plasma cells, which initially presented as bicytopenia, combined with primary lambda-type light-chain PCL characterized by marked phagocytosis of erythrocytes and platelets by neoplastic plasma cells.…”