title: Hypercalcemia associated with T-cell lymphoma-leukemia.
abstract: Two adults who had T-cell lymphoma-leukemia and recurrent hypercalcemia in the absence of radiographic evidence of bone disease are described. Bone histopathology showed marked osteoclastic activation. Bone resorbing factors, including both prostaglandin E and a material produced in the presence of a prostaglandin synthetase inhibitor, were detected in the in-vitro culture fluids of malignant cells of one of the patients. Serum levels of parathyroid hormone were not elevated. These findings suggest that hypercalcemia resulted from in-vitro osteoclast activation by tumor cell product(s), one of which may be similar, if not identical, to the lymphocyte product osteoclast-activating factor. Two other patients having T-cell lymphoma-leukemia and hypercalcemia have been identified in the literature: the malignant cells of one of these patients also released a calcium-mobilizing factor in vitro.
mesh_terms: D000328:Adult; D001862:Bone Resorption; D002118:Calcium / Q000097:blood*; D005260:Female; D006801:Humans; D008222:Lymphokines / Q000378:metabolism; D008223:Lymphoma / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D010010:Osteoclasts / Q000378:metabolism / Q000473:pathology; D010281:Parathyroid Hormone / Q000097:blood; D013601:T-Lymphocytes
chemical_list: D008222:Lymphokines; D010281:Parathyroid Hormone; C008718:osteoclast activating factor; D002118:Calcium