Hypercalcaemia associated with chronic lymphocytic leukaemia in a Giant Schnauzer

A 7‐year‐old male Giant Schnauzer was referred with a history of severe vomiting, lethargy, weight loss, polydipsia and polyuria. Detailed investigations revealed leucocytosis with a marked lymphocytosis, mild non‐regenerative anaemia, thrombocytopenia, hypercalcaemia and azotaemia. Circulating lymphocytes were small and well‐differentiated, and the same lymphoid population was present in bone marrow. Chronic lymphocyctic leukaemia with associated paraneoplastic hypercalcaemia was diagnosed. Immunohistochemical staining of a bone marrow biopsy revealed a neoplastic B‐cell line expressing CD79. The dog responded to therapy with prednisolone and chlorambucil for a period of 8 months.