Granuloma-Related Hypercalcemia Secondary to Silicone-Induced Granulomatous Lymphadenopathy: A Case Report.

Granuloma-mediated hypercalcemia is an uncommon cause of parathyroid hormone-independent hypercalcemia and is usually associated with sarcoidosis, chronic infection, or other inflammatory disorders. Foreign-body granulomatous reactions caused by silicone are rare and may occur years after exposure. We report the case of a 77-year-old woman with recurrent hypercalcemia, generalized weakness, gait instability, nausea, abdominal discomfort, and weight loss. Biochemical evaluation showed suppressed parathyroid hormone, normal 25-hydroxyvitamin D, elevated angiotensin-converting enzyme, and inappropriately normal 1,25-dihydroxyvitamin D. Cross-sectional and functional imaging demonstrated paraoesophageal and right axillary lymphadenopathy. Mammography and targeted axillary ultrasound supported silicone migration, with the ultrasound showing a characteristic snowstorm appearance. Core biopsy confirmed breast tissue with fat necrosis and foreign-body giant cell reaction to silicone, with no evidence of malignancy. The overall findings supported silicone-induced granulomatous lymphadenopathy as the cause of parathyroid hormone-independent hypercalcemia. This case highlights the importance of taking a detailed prior implant or cosmetic exposure history when evaluating unexplained hypercalcemia.