Syringoma biopsy. Image 2 of 2. View of a biopsy being taken from a syringoma on a patient's ear. A syringoma is a tumour of sweat glands in the skin. Syringomas are generally benign, but they may turn malignant if they are left untreated. Biopsies, the removal of a piece of living tissue for analysis, are commonly used to establish diagnoses. In the case of a tumour such as this one, it can be used to ascertain whether or not the tumour is benign or malignant. Surgical removal of the tumour is the usual treatment, provided it has not spread to other sites. For a view of the syringoma before the biopsy, see image M131/329.