Imaging findings in mandibular primitive neuroectodermal tumour: a report of a rare case and review of the literature

Abstract

Primitive neuroectodermal tumours (PNETs) are aggressive undifferentiated tumours that occur mainly in the central nervous system (CNS). Reviewing the literature, only six cases of primary PNET of the mandible have been reported. These rare tumours are usually overlooked in clinical practice. An 18-year-old woman who presented with dental caries and left cheek swelling was initially diagnosed with facial cellulitis, but the swelling persisted despite adequate intravenous antibiotic therapy. Subsequent ultrasound and MR examinations revealed a tumour originating from the left mandibular ramus. The ultrasonography-guided percutaneous core needle biopsy confirmed the diagnosis of peripheral PNET. The radiographic features of mandibular PNETs are similar to those of PNETs in other regions, except for haemorrhage, necrosis and calcification. In addition, this is the first reported case with sonographic and MR images of this rare tumour, and the first case that was diagnosed based on the ultrasonography-guided percutaneous core needle biopsy. Using these image characteristics, mandibular PNETs can be diagnosed more accurately.

CT and clinical findings of peripheral primitive neuroectodermal tumour in children

“…pPNETs occur at any age but mainly affect children and young adults. 6,[9][10][11][12][13][14][15][16]20 In our series, the age range was from 4 months to 15 years (mean age: 7.7 years), which was consistent with the literature, 6,10,20 although there were infant patients reported in other studies. 8,9 pPNET can occur at any location, of which the thoracopulmonary region, head and neck, and extremities are the most common sites.…”

“…8,9 pPNET can occur at any location, of which the thoracopulmonary region, head and neck, and extremities are the most common sites. 9,10,14 In our series, the sites of tumours were in the abdomen and pelvis (n 5 6), head and neck (n 5 4), spine (n 5 3), ilium (n 5 2), femur (n 5 1) and chest (n 5 2); which were a little different from the reports above. 9,10,14 In our study, the rare locations of carotid sheath, parotid gland, pancreas, adrenal gland and kidney were described.…”

“…9,10,14 In our series, the sites of tumours were in the abdomen and pelvis (n 5 6), head and neck (n 5 4), spine (n 5 3), ilium (n 5 2), femur (n 5 1) and chest (n 5 2); which were a little different from the reports above. 9,10,14 In our study, the rare locations of carotid sheath, parotid gland, pancreas, adrenal gland and kidney were described. Comparing with the size of pPNET in different locations, we found that the size of the lesions arising in the spine (,5 cm) was smaller than that of the lesions arising in organs, pleura, soft-tissue space and extremities; and tumours arising from the chest or abdominopelvic cavity were larger than those arising elsewhere, which was consistent with that of a previous report.…”

“…3,21 Diverse radiological findings have been reported in patients with pPNETs; 6,7,[9][10][11][12][13][14][15][16]22 but for paediatric pPNETs, most of them are cases arising in common locations and are reported in the form of case reports. 6,[9][10][11][12][13][14][15][16] In our series, the CT findings of 18 paediatric pPNETs were described, and the case number was less than that of the study of Dick et al, 9 which reported 25 young patients with pPNET having CT scans. In our study, both common and uncommon locations of pPNETs were included.…”

“…The clinical and pathological characteristics of pPNET are definite, but the radiological features have been reported in only a few studies, and in these few studies, most of them are cases arising in the common locations and are reported in the form of case reports. 6,[9][10][11][12][13][14][15][16] This report describes the clinical features, and CT and pathological findings in 18 paediatric patients diagnosed with pPNETs in different locations, as a way to enhance the recognition of these tumours and help differentiate these from the other types of paediatric malignant bone and soft-tissue tumours.…”