Paradoxical scintigraphy bone scan findings with malignancy‐associated extreme hypercalcemia

We report the first case of extreme hypercalcemia (Ca 2+ >6.0 mmol/L) as the initial presentation of de novo metastatic breast cancer. Following treatment and stabilization of the patient, imaging revealed a large breast mass and widespread osseous metastases. Whole body bone scintigraphy demonstrated significant extra osseous uptake of radiotracer in the lungs, liver, and kidneys—a rare phenomenon secondary to profound hypercalcemia. Biopsy revealed estrogen receptor (ER) positive breast carcinoma, for which the patient was treated.