Enzyme histochemical study on bone tumors.

A total of 19 cases with bone tumors, including six osteosarcomas. three giant cell tumors of bone, one malignant fibrous histiocytoma, four nonossifying fibromas, four chondromas and one chondrosarcoma, were examined as to enzyme histochemistry; the enzymes consisted of alkaline phosphatase (ALPase), acid phosphatase (ACPase), nonspecific esterase (NSE), adenosine triphosphatase (ATPase), 5'-nucleotidase (5'-Nucl) and beta-glucuronidase (beta-Gl). Osteosarcoma was strongly positive for ALPase followed by 5'-Nucl. Giant cell tumor, malignant fibrous histiocytoma and nonossifying fibroma showed enzyme histochemistry similar to each other: multinucleated giant cells and round cells in these tumors were strongly positive for ACPase, NSE, ATPase and 5'-Nucl simulating osteoclasts and histiocytes, whereas spindle cells were positive for ATPase and 5'-Nucl in their cytoplasm and weakly positive for ACPase. Chondroma and chondrosarcoma were focally positive for ACPase and NSE; the ACPase was sensitive to tartaric acid treatment. These observations showed that ALPase activity is very characteristic to osteosarcoma, and is useful for its diagnosis. From enzyme histochemistry, giant cell tumor, malignant fibrous histiocytoma and nonossifying fibroma can be regarded as a histiocyte-derived tumor of bone in contrast to osteosarcoma and cartilaginous tumors.

A tumor composed of myofibroblasts: an ultrastructural study.

A subcutaneous tumor of the right temporal region of head was removed from an 8-year-old boy. This tumor was studied by light and electron microscopy. He was found to have had a retroperitoneal inflammatory fibrous histiocytoma which had been excised seven years ago. The subcutaneous tumor histologically consisted of spindle cells in fascicles, which did not arrange in a storiform or herring-bone pattern. Electron microscopically, this tumor was chiefly composed od myofibroblasts. electron microscopy is essential to determine the cell types of a tumor and we have classified this tumor as a tumor of myofibroblasts. The relationship between the retroperitoneal tumor and the head tumor was discussed.

Giant cell tumor bone. Enzyme histochemical, biochemical and tissue culture studies.

Three giant cell tumors of bone (2 benign and 1 malignant) were examined enzyme-histochemically, and a tissue culture study of the malignant case was performed. Multinucleated giant cells and mononuclear round cells had similar activities of ACPase and non-specific esterase with a diffuse strong reaction. ATPase and 5'-nucleotidase reactions were strongly positive in the cytoplasm of multinucleated giant cells, and were seen not only in the cytoplasm but also on the cell membrane of round cells. The proliferating spindle cells in the malignant case were faintly positive for ACPase and non-specific esterase and were less positive for ATPase and 5'-nucleotidase on the cell membrane. The multinucleated giant cells and mononuclear round cells resembled histiocytes in the activities of 4 hydrolytic enzymes, and the multinucleated giant cells had enzyme activities similar to those of osteoclasts from new-born rat skull. The malignant giant cell tumor and cells in its tissue culture showed ALPase activity preferentially on the cell membrane of the spindle cells, and rarely on round cells or multinucleated giant cells. ALPase was resistant to heat treatment and was found to be the type IV isoenzyme by diffusion electrophoresis. The origin of the giant cell tumor of bone and the significance of the ALPase activity are discussed.

Cytochemical markers of murine leukemias and lymphomas.

Seven transplantable leukemias and lymphomas which occurred in NZB mice were characterized immunologically and cytologically as B-cell type of L66-, 2709-, 2769- find S77-lines, and T-cell type of TH17-, TH90- and S29-lines. These were also studied with enzyme histochemistry in tissue sections. All B-cell tumors revealed strong activities of ATPase and 5'-nucleotidase and one expressed A1Pase activity on the cell surface. Two thymic lymphomas (TH17- and TH90-lines) and one T-cell leukemia (S29-line) showed negative reactions of ATPase and 5'-nucleotidase but positive activities of AcPase and non-specific esterase localized in their cytoplasms. A1Pase activity was expressed in TH90-lymphoma but not in TH17- and S29-lymphomas. A1Pase recognized in L66- and TH90-lymphomas showed similar reaction to those of Nagao's isoenzyme. The splenic follicles of normal NZB mice reacted to ATPase and 5'-nucleotidase in B-cell area (primary follicles) and to AcPase and non-specific esterase in T-cell area (PALS) with the localized reaction. Data suggest that four enzymes of ATPase, 5'-nucleotidase, AcPase and non-specific esterase are useful for the differentiation of B- and T-cells and their malignant counterparts.