Hypercalcaemia induced by tumour-derived parathyroid hormone-related protein and multiple cytokines in diffuse large B cell lymphoma, not otherwise specified.

摘要

Sir,Hypercalcaemia is most commonly associated with primary hyperparathyroidism and malignancy. In haematological neoplasms, it often occurs in multiple myeloma (about 33% of cases), and it is nearly always associated with extensive osteolysis in the skeletal system. Only 1-2% of patients with lymphoma and leukaemia develop hypercalcaemia (except in adult T cell leukaemia, where it is common). Here we report the first known immunohistochemically confirmed case of diffuse large B cell lymphoma, not otherwise specified (DLBCL, NOS) with vertebral compression fracture, bone metastasis, and hypercalcaemia thought to have been induced by tumour-derived parathyroid hormone-related protein (PTHrP), interleukin-6 (IL-6), and tumour necrosis factor-alpha (TNF-alpha). Because PTHrP, proinflammatory cytokines, and their receptors are produced by DLBCL, NOS itself, they may play an important role in the pathogenesis of hypercalcaemia and tumour progression in some cases of the disease.