FDG-PET in an Eccrine Carcinoma of the Scalp

Eccrine carcinoma of the sweat gland is rare. A 45-year-old man presented with one rapidly growing mass each in the occipital region of both the head and nape, accompanied with bilateral cervical lymphadenopathies. An incision biopsy of the involved skin showed a picture of an adenocarcinoma, either primary or metastatic. Whole-body PET revealed increased FDG uptake into the corresponding tumors and lymph nodes with no detectable focal abnormalities elsewhere. FDG-PET excluded an adenocarcinoma metastasized from another part of the body and provided the diagnosis. Additionally, FDG-PET may be used as a biological marker for assessing the malignant potential of the tumor and predicting the outcome of the disease.