Calciphylaxis due to metastatic well-differentiated neuroendocrine carcinoma

A 70-year-old man with history of metastatic well-differentiated neuroendocrine carcinoma was presented to the hospital with a painful left lower extremity ulcer which started around 3 months prior to presentation. He was treated with antibiotics for cellulitis on multiple occasions with no improvement in his symptoms. On initial laboratory evaluation, he was found to have acute kidney injury and a normal calcium level. The patient underwent a skin biopsy and was found to have cellulitis and calciphylaxis of small-sized and medium-sized vessels. Since the patient did not have any underlying risk factors of calciphylaxis, the most likely cause of his calciphylaxis was thought to be his underlying malignancy. Physicians should keep this differential in mind while treating non-healing ulcers in such patients since they are at higher risk of superimposed infections and usually require aggressive wound care.