Subcutaneous sarcoidosis mimicking an infiltrative malignant soft-tissue tumor: Two case reports and a literature review

Subcutaneous sarcoidosis is an extremely rare inflammatory disease, and the imaging characteristics are unknown. A 72-year-old woman had an elastic hard nodule, which was gradually growing, on her left upper extremity that had been present for several years. The subcutaneous nodule showed an iso-intense signal on both T1-and T2-Magnetic resonance (MR) images. Extended enhancement to the triceps fascia was observed. A 68-year-old man noticed a hard nodule on his right thigh with tenderness one month previously. The subcutaneous nodule showed an iso-intense signal on both T1-and T2-MR images, and was enhanced with the surrounding soft-tissues, to the quadriceps fascia. Biopsy revealed a diagnosis of sarcoidosis. Subcutaneous sarcoidosis should be kept in mind when imaging shows an infiltrative soft-tissue nodule.