Keratocystoma – facial resection in suspicion of malignancy! Case report of a rare tumor entity with benignancy in the final histological analysis

Introduction:

Tumors of the major salivary glands are usually benign. Among these benignomas the keratocystoma is a rare, largely unknown entity.

Case report:

A 15-year-old female patient presented with a painless and solid node of the left parotid gland, measuring 2.5 cm. After imaging and cytology, the diagnosis was still pending. From the diagnostic and therapeutic point of view, we performed a parotidectomy with intraoperative facial nerve monitoring. The neurolysis of some branches of the facial nerve was microscopically not possible because of fibrous and nerve-surrounding tumor growth. In state of not knowing the present dignity, the calculated nerve-transsection followed by microanastomosis was conducted. Histologically, the tumor revealed multiple keratin-filled cysts as well as single solid epithelial cell nests without evidence of malignancy. Keratocystoma has been diagnosed. While the patient initially suffered from a partial facial nerve palsy, it shows a normal function 10 months after the procedure. Until now there is no indication of recurrence of the tumor.

Discussion:

Keratocystoma is first mentioned in relevant literature in 2001. To the best of our knowledge, only seven cases have been published yet. It is considered as a benign tumor of major salivary glands; however, because of its clinical features it is listed as a differential diagnosis of malignant salivary tumors in the WHO Classification for Head and Neck Cancer of 2005. The diagnosis is made histologically. Due to the macroscopic characteristics of the tissue a radical surgical procedure with controlled facial nerve resection is inevitable. If microsurgical techniques for nerve reconstruction are used consistently, however, this does not affect the functional result.

Publication History

Publication Date:
18 April 2018 (online)