A Rare Paraneoplastic Syndrome That Presages a Poor Prognosis in Urothelial Carcinoma: A Case Report

Isolated hypercalcaemia, leukocytosis or thrombocytosis is common in cancer patients, but the association of the first two is rarely described and the triple paraneoplastic syndrome is even more exceptional. Their concomitance portends a poor prognosis in solid tumor patients. We report the case of a 53-year old man with hypercalcaemia-leukocytosis-thrombocytosis paraneoplastic syndrome associated with a urothelial carcinoma which was fatal 4 months after diagnosis. Pathophysiology remains unclear but secretion of parathyroid hormone related protein (PTHrp) and cytokines such as granulocyte colony stimulating factor (G-CSF) as well as activation of thrombopoietin (TPO) receptor might be implicated. Although very rare, this paraneoplastic syndrome should be considered in solid tumor patients presenting with concomitant hypercalcaemia, leukocytosis and thrombocytosis, as it presages a poor prognosis with a rapid disease progression, and should be looked for and when present taken into account in the management of urothelial carcinoma, where no biological prognostic marker is available in clinical practice.