Hypercalcemia associated with cancer can result from osteolytic metastases, but in most cases hypercalcemia results from tumoral secretion of a parathyroid hormone—related protein (PTHRP), an analogue of the parathyroid hormone purified recently.1Squamous cell carcinoma (SCC) of the lung and oral cavity and breast adenocarcinoma are the most common causes of this paraneoplastic syndrome, also called humoral hypercalcemia of malignancy (HHM). We report the first case, to our knowledge, of HHM associated with an extensive metastatic cutaneous SCC. Report of a Case. A 53-year-old man presented with a voluminous ulcerated tumor of the upper back, which had developed over a 15-year period (Figure). Large axillary lymph nodes appeared 3 years prior to our examination. A complete blood count showed hyperleukocytosis and thrombocytosis. Results of renal and liver function tests and human immunodeficiency virus type 1 and 2 serologic tests were normal or negative. Severe hypercalcemia was present at calcium
