A Case of Tumoral Calcinosis in the Left and Right Iliac Region

Abstract

A 77-year-old woman noted subcutaneous masses in the left and right iliac region 3 months prior to her first visit. She came to our hospital because they increased in size. At the time of the first visit, a fist-sized elastic hard subcutaneous mass was found in the left iliac region and a 4×2cm-sized subcutaneous mass with a reddish elevated surface was found in the right iliac region. Each subcutaneous mass was biopsied. Histopathological examination demonstrated widespread calcification from the dermis to the subcutaneous tissue in both lesions. Infiltration of inflammatory cells around the calcification was observed, but no foreign body giant cells or pseudocyst-like changes were observed. Blood tests, including Ca, P, and PTH levels, were normal, and no abnormalities in collagen-related autoantibodies or tumor markers were found. Both MRI and CT of the pelvic region revealed soft shadows, mainly calcification, in the subcutaneous fat of the lateral gluteal muscles on both sides. Based on these findings, a diagnosis of idiopathic cutaneous calcinosis (tumoral calcinosis) was made. As there was no increase in the size of the lesions after the diagnosis, total excision was not performed and the patient was followed up every 3 months. It has now been one year and nine months since the diagnosis of the disease, but there has been no increase in size in either mass. There have been 16 reported cases of tumoral calcinosis in Japan since 1983. Of these, only three cases of multiple lesions were found, including our case. In cases of multiple subcutaneous masses in the iliac region, cutaneous calcinosis should be included in the differential diagnosis, and blood tests and imaging studies should be actively performed. Skin Research, 20 : 320-324, 2021