[Eccrine porocarcinoma of the cheek skin with parotid gland infiltration].

BACKGROUND

Eccrine porocarcinoma is a rare malignant tumor, arising from the intraepithelial ductal parts of the sweat glands. Although the clinical appearance is variable, some tumors present with a diameter of 10 cm or more. In most cases the tumor presents as a slowly growing painless mass.

PATIENTS AND METHODS

A case of a 61 year old male patient is presented, who was admitted because of a peripheral facial nerve palsy. The patient reported about a sting in this area some ten years ago with a persistent swelling. Four years ago this lesion began to grow slowly.

RESULTS

Clinically a huge mass in the left cheek extended to the parotid gland was obvious. The patient underwent radical tumor excision with histologically clear margins. The defect was reconstructed by a microvascular forearmflap, the facial nerve was reconstructed using either a graft from the suralis nerve (for the upper part of the facial nerve) along with a hypoglossal facial nerve anastomosis for the lower part of the facial nerve. Postoperative radiation therapy was added. Histologically an eccrine porocarcinoma was confirmed with an infiltration of the facial nerve and the parotid gland. Lymph nodes in the neck were negative. DNA image cytometry achieved a DNA malignancy grade of 0.73, the immunohistochemical assessment using a monoclonal antibody against the proliferation antigen MIB-1 achieved a proliferation rate of < 10 %.

CONCLUSIONS

Although very rare eccrine porocarcinoma should be considered in the differential diagnosis of slowly growing skin masses in the face. Therapeutically a radical resection with histological clear margins is recommended, in case of lymph node metastases with additional postoperative radiotherapy.