Hypercalcemia–leukocytosis syndrome from non-schistosomiasis-associated squamous cell carcinoma of the urinary bladder: a case report and review of the literature

BACKGROUND: Non-schistosomiasis-associated squamous cell carcinoma of the urinary bladder is less common in the Western world. Limited information on its possible paraneoplastic syndromes exists. Leukocytosis tends to commonly be regarded by clinicians as an indication of sepsis, rather than a feature of paraneoplasia, potential surrogate marker for recurrence, and prognostic marker. Accompanying hypercalcemia may be missed entirely. CASE PRESENTATION: A 66-year-old Caucasian man presented with visible painless hematuria and symptomatic hypercalcemia. Investigations revealed a squamous cell carcinoma of the urinary bladder with marked leukocytosis. Hypercalcemia and leukocytosis resolved following radical cystectomy, recurred with nodal recurrence and regressed with radiotherapeutic control. Subsequently, serum leukocyte and calcium assays were included in his follow-up protocol. His survival was 20 months by the time of the report. CONCLUSION: This report highlights hypercalcemia–leukocytosis syndrome as a paraneoplastic manifestation of non-schistosomiasis-associated squamous cell carcinoma to reemphasize the need for clinicians to assay for calcium in the presence of leukocytosis in such patients. Prompt identification and control of the paraneoplastic derangements, with treatment of the cancer recurrence it may connote, is advocated to provide a chance for better long-term outcomes in these patients.