Myopericytoma: A Review of Twenty-Three Cases Over Twelve Years and a Case Report of a Rare Neoplasm

Myopericytoma is a rare soft tissue tumor with a predilection for the distal extremities. It is commonly found in the skin and subcutaneous tissues and usually takes a benign course. Current knowledge is limited to isolated case series and reports; hence, this study aims to report our tertiary institution's experience with this uncommon entity. A review of our institution's pathology records for cases of myopericytoma was performed. From January 2009 to September 2020, 23 cases of myopericytoma were identified and their clinicopathologic features were reported. A unique case of myopericytoma of the ankle from the series was also highlighted as a case report. Among the 22 cutaneous cases, 18 were in the extremities and 4 in the head and neck. One patient had an intracranial lesion. Most patients developed asymptomatic nodules (72.2%), but 1 patient had a locally aggressive tumor on presentation. None recurred despite marginal excision in some patients (80.0%). In conclusion, pathologists and surgeons who encounter this rare neoplasm can reassure patients of its benign tendency.

Imaging features of myopericytoma arising from the parotid gland: Report of 2 cases and literature review

RATIONALE

Myopericytoma of the parotid gland is a rare condition of which preoperative definitive diagnosis is relatively challenging. The purpose of this case report is to highlight the radiologic features of myopericytoma of parotid gland.

PATIENT CONCERNS

A 62-year-old man presented with a history of a walnut-size mass in left parotid gland when yawned for half-month, and a 48-year-old woman complaint about a grape-size, painless mass behind the right ear for a month.

DIAGNOSES

Radiological examinations suggested that both lesions were cyst-solid mixed lesions with relatively smoothed margins, with or without significant enhancement while the lesion without enhancement had a hemorrhage. Then a diagnosis of benign tumor arising from the parotid gland was made. Final diagnosis of myopericytoma was confirmed by histopathological and immunohistochemical examinations after surgical resection.

INTERVENTIONS

Both patients underwent excision of the tumor and the superficial parotidectomy with facial nerve preservation.

OUTCOMES

Both patients recovered without any intraoperative or postoperative complication and had no signs of recurrence during a 17-month and 5-year follow-up.

LESSONS

Parotid gland myopericytoma is an exceedingly rare tumor which diagnosis can be challenging, and this is the first published report specifying the magnetic resonance features of the disease.

Myopericytoma of the Base of the Finger: Radiological and Pathological Description of a Rare Benign Entity

A previously healthy 46-year-old woman presented with a mass lesion between the bases of the fourth and fifth fingers of the right hand. The mass had grown progressively over 2 years and started to cause practical difficulties in everyday life. Imaging depicted a hypervascular and well-circumscribed soft tissue tumor with imaging characteristics of a sarcoma. The lesion was treated surgically. The final diagnosis of the specimen upon pathology was a myopericytoma, a benign smooth-muscle cell neoplasm. Myopericytoma is a rare disease entity; however, it is important because it can mimic more ominous conditions.