Hemangiopericytoma of the neck.

Hemangiopericytoma (HPC) is an exceedingly rare tumor of uncertain malignant potential. Approximately 300 cases of HPC have been reported since Stout and Murray described HPCs as "vascular tumors arising from Zimmerman's pericytes" in 1942. After further characterization, the WHO reclassified HPC as a fibroblastic/myofibroblastic tumor. Long term follow up is mandatory because the histologic criteria for prediction of biologic behavior are imprecise. There are reports of recurrence and metastasis many years after radical resection. The head and neck incidence is less than 20%, mostly in adults. We report herein a case of HPC resected from the neck of a 74-year-old woman, who presented in our department with a painless right-sided neck mass. The mass was well circumscribed, mobile and soft during the palpation. The skin over the tumor was intact and normal. Clinical diagnosis at this time was lipoma. A neck computer tomography scan showed a large submucosal mass in the neck, which extended in the muscular sites. The tumor was completely removed by wide surgical resection. During surgery we found a highly vascularised tumor. The histopathologic examination revealed a cellular, highly vascularized tumor. The diagnosis was that of solitary fibrous tumor, cellular variant, with haemangiopericytoma-like features. The patient had normal postoperative course of healing and 24 months later she remains asymptomatic, without signs of recurrence or metastases.

Epidermoid cyst of the floor of the mouth: two case reports.

INTRODUCTION: Epidermoid cysts that appear in the midline floor of the mouth are, usually, a result of entrapped ectodermal tissue of the first and second branchial arches, which fuse during the third and fourth weeks in utero. The incidence in the floor of the mouth of the oral cavity is rare and development sites are the sublingual, submaxillary and submandibular spaces. It was present two cases of epidermoid cyst of the floor of the mouth and discussed the different surgical approaches for this lesion. CASES PRESENTATION: Two cases of midline epidermoid cysts of the floor of the mouth are presented, evaluating the different surgical approaches. The preoperative assessment was made using ultrasonography and computed tomography in both cases. Regarding surgical techniques used, a transcutaneous approach was adopted when the cysts were under the geniohyoid muscle and a midline incision of the oral mucosa along the lingual frenulum was used for sublingual cysts. During the postoperative course, there were no complications, except for mild edema in one case. Follow-up ranged between 5 months and 4 years; no recurrence or malignant changes were observed. CONCLUSIONS: Surgery of epidermoid cyst of the floor of the mouth is the treatment of choice. Access depends on the lesion's location in relation to the mylohyoid or geniohyoid muscles. If the cyst is located over the mylohyoid, surgery is carried out only through the oral cavity, whereas the extraoral incision was necessary only when the cysts were under the geniohyoid muscle.