PTH and adult T-cell leukemia/lymphoma: ATLL associated hypercalcaeima: The pathogenesis of hypercalcaemia in patients with ATLL has been associated with elevated serum macrophage colony-stimulating factor (M-CSF) levels, over expression of receptor activator of nuclear factor kappa B ligand (RANKL), ATLL infiltration into the bone marrow and perhaps parathyroid hormone-related peptide (PTH-rP) secretion [52].