[Hypercalcemia associated with parathyroid hormone-related protein(PTHrP)in a patient with diffuse large- type B-cell...

We report a patient with diffuse large-type B-cell lymphoma showing hypercalcemia and a raised PTHrP serum level. He was a 72-year-old man with a history of multiple bone fractures due to a traffic accident 3 month ago, and was transferred to our hospital for further evaluation of a hepatic mass and for his rapidly deteriorating general condition. He had been in good health until about 2 weeks ago, but he developed dehydration, azotemia, lethargy, and altered mentality on admission. Laboratory tests revealed hypercalcemia of1 5. 3mg/dL. The hypercalcemia was associated with a high plasma concentration of PTHrP, whereas the parathyroid hormone(PTH-C)was undetectable. After forced hydration and administration of furocemide and calcitonin, hypercalcemia was improved. CT and MRI imaging showed para-aortic lymphadenopathy and a huge mass involving most of the light hepatic lobe and spleen. The pathological diagnosis at liver biopsy was DLBCL. He received six courses of chemotherapy with R-CHOP and is now stable. There was no recurrence of hypercalcemia or an elevation of PTHrP serum level during chemotherapy. The existence of PTHrP produced by tumor cells was suspected, and may have been related to the hypercalcemia in our case.