Non-ossifying fibromas usually occur in the metaphysis of the long bones in children, and are extremely rare in the mandible. Here, we present a case of non-ossifying fibromas which occurred in the mandible of a 4-year-old boy. The patient had no complaint of ache. Laboratory blood examination of serum calcium, phosphorus, and parathormone levels was normal. Computed tomography of the maxillofacial region showed a well-defined osteolytic lesion affecting the right mandible. Microscopically, the lesion showed whorled bundles of spindle-shaped fibroblasts, as well as foam cells, mingled with scant multinucleated giant cells, without any bone formation. It is necessary to distinguish non-ossifying fibromas from other giant cell-containing lesions because of the extremely infrequent occurrence of this lesion in the mandible. We reviewed the histologic features of 14 cases of non-ossifying fibromas involved in the jaw.

BACKGROUND: Benign fibrous histiocytoma (BFH) is a rare bone tumor, extremely seldom in the spine.
METHODS: We present a 52-year-old patient diagnosed with a BFH in the thoracic spine treated with total en bloc spondylectomy. A review of the published literature was also conducted.
RESULTS: Non-ossifying fibroma (NOF) and BFH are named as one tumor called NOF/BFH. A total of 20 spinal BFHs have been previously reported, mainly involving the posterior elements. We present a BFH with total vertebral involvement. Curettage and excision are the main treatment options with limited recurrence.
CONCLUSIONS: This is the first total vertebral BFH up to now. Spinal BFH occupies rather low aggressiveness. With rather limited recurrence and malignant degeneration, surgical interventions seem enough for its management.

Tricho-rhino-phalangeal syndrome (TRPS) is a rare autosomal dominant genetic disorder characterized by distinctive craniofacial and skeletal abnormalities, while non-ossifying fibroma (NOF) is a common benign bone tumour in children and adolescents. To date, no case of TRPS coexisting with NOF has been reported. This report presents a 12-year-old girl who had the characteristic features of tricho-rhino-phalangeal syndrome and non-ossifying fibroma with a fibula fracture.
A 12-year-old girl was admitted to the Department of Endocrinology and Diabetes for evaluation of brachydactyly and a right fibula fracture. Clinical examination revealed sparse scalp hair, a characteristic bulbous pear-shaped nose, and brachydactyly with significant shortening of the fourth metatarsal. Neither intellectual disability nor multiple exostoses were observed. Radiography of both hands showed brachydactyly and cone-shaped epiphyses of the middle phalanges of the digits of both hands with deviation of the phalangeal axis. Genetic analysis of TRPS1 identified a heterozygous germline sequence variant (p.Ala932Thr) in exon 6 in the girl and her father. Approximately 1 month before being admitted to our department, the girl experienced a minor fall and suffered a fracture of the proximal fibula in the right lower limb. The pathological cytological diagnosis of the osteolytic lesion was NOF. Ten months following the surgery, the lesion on the proximal fibula of the girl disappeared.
In conclusion, the present study is the first to report a rare case of NOF with a pathologic fracture in the fibula of a girl with TRPS. The identification of a missense mutation, (p.Ala932Thr), in exon 6 of TRPS1 in this kindred further suggested that the patient had type I TRPS and indicated that mutations in this exon may be correlated with more pronounced features of the syndrome. Radiological techniques and genetic analysis played key roles in the definitive diagnosis.