BACKGROUND: Benign notochordal cell tumours (BNCTs) represent a rare entity within the spectrum of bone neoplasms, which typically arise in the axial skeleton. Although these tumours are often benign, their diagnosis and management pose significant challenges due to their histological similarity to more aggressive lesions, such as chordomas. Understanding of the clinical behaviour, diagnostic nuances, and optimal management strategies for BNCTs continues to evolve.
METHODS: Benign notochordal cell tumours of the vertebra are usually asymptomatic and identified on imaging and should be distinguished from chordomas, which has a more aggressive clinical course. This report describes a 15-year-old girl with lumbosacral pain and a diagnosis of a benign notochordal cell tumour, which affects a large part of the S1 vertebra in the lumbar spine, highlighting the diagnostic challenges encountered, the role of radiological and histological investigations, and the ultimate determination of the benign nature of the tumour.
CONCLUSIONS: This report highlights the approach taken for the diagnosis of a benign notochordal cell tumour of the vertebra and the importance of excluding differential diagnoses. By exploring the intricacies of this case, we contribute to the growing body of literature surrounding BNCTs, with the aim of improving clinical awareness and management strategies for this uncommon bone tumour.

BACKGROUND: Mazabraud\'s syndrome (MS) is a rare and slowly progressive benign disease characterized by the concurrent presence of fibrous dysplasia of bone and intramuscular myxoma, and is thought to be associated with mutations of the GNAS gene. To date, only about 100 cases of MS have been reported in the literature, but its standard treatment strategy remains unclear.
METHODS: We report two cases of MS in young women who underwent different treatments based on their symptoms and disease manifestations. The first patient, aged 37, received internal fixation and intravenous bisphosphonate for a pathological fracture of the right femoral neck, excision of a right vastus medialis myxoma was subsequently performed for pain control, and asymptomatic psoas myxomas were monitored without surgery. Genetic testing confirmed a GNAS gene mutation in this patient. The second patient, aged 24, underwent right vastus intermedius muscle myxoma resection, and conservative treatment for fibrous dysplasia of the ilium. These patients were followed-up for 17 months and 3 years, respectively, and are now in a stable condition.
CONCLUSIONS: Various treatments have been selected for MS patients who suffer different symptoms. The main treatment for myxomas is surgical resection, while fibrous dysplasia is selectively treated if the patient experiences pathological fracture or severe pain. However, given the documented instances of malignant transformation of fibrous dysplasia in individuals with MS, close follow-up is necessary.

Fibrous dysplasia (FD) is a rare benign skeletal disorder that replaces normal bone with fibrous tissue and immature woven bone. We present a case of a 13-year-old girl with right-sided facial swelling and craniofacial deformity since birth, accompanied by nasal obstruction and difficulty in breathing and swallowing. Computed tomography (CT) imaging revealed an expansile bony lesion with a ground-glass matrix involving multiple craniofacial bones. Histopathological examination confirmed the diagnosis of FD. Management involved regular monitoring and conservative measures, with surgical intervention reserved for symptomatic progression or cosmetic concerns. This case underscores the importance of considering FD in the differential diagnosis of craniofacial asymmetry and highlights the collaborative approach to patient care. Further research is needed to optimize management strategies and outcomes for pediatric patients with FD.

Craniofacial fibro-osseous lesions (CFOLs) are a diverse group of relatively rare entities whose etiology ranges from reactive to dysplastic with a potential for malignant transformation. It is distinguished by the replacement of bone with fibrous tissue, that subsequently develops different degrees of calcification. Fibrous dysplasia (FD) is a component of the fibro-osseous lesion spectrum. The clinical spectrum of FD is wide, ranging from minor monostotic lesions affecting a single bone to devastating polyostotic disease involving the entire skeleton. FD produces asymmetry, which impairs face aesthetics. FD leads to bone differentiation, disintegration, and disorganization. It depicts a cellular collagenous stroma lacking mitotic figures and pleomorphism. Blood capillaries are evenly distributed, as are elongated trabeculae of woven or lamellar bone with uneven curves (often referred to as the Chinese letters pattern). Three types of FD patterns can be identified by computed tomography (CT) imaging: a cystic pattern, a homogeneously dense pattern, and a ground-glass pattern. The cornerstone of treatment is surgery, although the method varies depending on the location, size, and symptoms of the lesion. As an alternative to surgery, the use of bisphosphonates to reduce osteoclastic activity is under consideration. In this case series, we present three cases of FD involving the maxilla and mandible. We aim to correlate the clinical presentation, histological features, and radiographic findings, to promote early diagnosis, treatment, and better prognosis of the patient.

Cherubism, an uncommon genetic disorder, manifests as painless swelling in both jaws. A 20-year-old male presented with symmetrical swelling in both the mandible and maxilla. The jaws exhibited bilateral expansion, typical of this condition. Dentofacial abnormalities associated with cherubism stem from mutations in the SH3BP2 gene, which plays a crucial role in regulating osteoblasts and osteoclasts. In summary, cherubism is a genetic disorder characterized by non-cancerous jaw bone lesions. Surgical intervention may be necessary for functional or aesthetic concerns.

A rare benign bone condition called monostotic fibrous dysplasia (MFD) is characterized by the growth of fibrous tissue in place of a normal bone. It may lead to deformity in the affected bone, pain, and a pathologic fracture due to bone weakness. Hereunder, a case report of MFD in a 17-year-old male adolescent presenting to the hospital with localized bone pain and swelling in his right tibia is presented. After clinical examination and radiographic imaging, a provisional diagnosis of benign osteolytic lesion was considered. A magnetic resonance imaging (MRI) scan of the leg suggested the possibility of fibrous dysplasia or adamantinoma. The patient was managed with an intralesional curettage of the dysplastic bone and packing the cavity with blocks of a synthetic bone. The excised material was sent for histopathology, which established the diagnosis of fibrous dysplasia.

Desmoplastic fibroma (DF) is a rare benign bone tumor adopting an aggressive behavior, representing a challenge for clinical and radiographic diagnosis. This case report focused on a 31-year-old man with a large mandibular lesion with severe displacements of the mandibular teeth. Only a combination of paraclinical findings allows a definitive diagnosis to be made. Cervicofacial MRI revealed a low T1 signal intensity with peripheral enhancement after Gadolinium, and T2 hyperintense signal, while PET scan showed a moderate metabolism. Bone biopsy with immunohistochemical analysis allowed for definitive diagnosis of DF after eliminating the main differential diagnosis (fibrous dysplasia, fibrosarcoma, desmoid tumor, and osteosarcoma). The patient was successfully treated by large mandibular resection and reconstruction with a free-fibular bone flap\".

UNASSIGNED: Fibrous dysplasia (FD) is a benign skeletal disorder characterized by the replacement of normal bone tissue with disorganized fibrous tissue. Fractures are a significant complication of FD, particularly in the proximal femur, where deformities such as Shepherd\'s crook deformity can increase the risk.
UNASSIGNED: We present a case study of a 44-year-old male with unilateral monostotic FD, Shepherd\'s crook deformity, and a pathological femoral shaft fracture. The initial surgical approach involved valgus osteotomy, dynamic condylar screw (DCS) fixation, and multiple osteotomies of the femoral shaft. However, the patient experienced a refracture and implant failure, necessitating a second surgical intervention with a double-angled DCS and additional fixation. Post-operative follow-up revealed successful bone union and deformity correction, although a limb length discrepancy was noted.
UNASSIGNED: This case highlights the challenges in managing FD-related fractures and the importance of addressing deformities and achieving optimal alignment. Individualized treatment approaches, careful implant selection, and post-operative rehabilitation are crucial for successful outcomes in FD-associated fractures.

OBJECTIVE: We report a case of fibrous dysplasia (FD) with aneurysmal bone cyst (ABC)-like change in a child with orbital involvement, review the related cases, and discuss clinical features, therapy, and prognosis of this disease.
METHODS: A 10-year-old girl had right proptosis (degree of exophthalmos: OD 16 mm, OS 13 mm) and limited vision (visual acuity: OD 1.0, OS 0.8) without trauma. Preoperative CT showed a 5.0*4.3 cm right-sided crania-orbital communicating tumor. MRI indicated a well-defined multicystic mass with scattered fluid levels and soap bubble-like alterations. The child underwent total tumor resection and orbital parietal titanium mesh reconstruction. At 20 months of follow-up, the child has recovered from ocular problems, and the tumor has not recurred.
CONCLUSIONS: FD combined with ABC rarely occurs in orbit and generally begins with ocular symptoms. The etiology is uncertain. Early diagnosis and surgery are essential. Complete resection is suggested whenever possible because residual lesions may recur.

UNASSIGNED: FD is relatively rare in the craniofacial region, accounting for only 20% of all cases. Currently, two general subtypes of FD are recognized: monostotic and polyostotic. The monostotic form is more frequent, accounting for 75% to 80% of fibrous dysplasia cases.
UNASSIGNED: An 18-year-old male presented with the complaint of bony-hard swelling over the forehead for 8 years. Radiology showed an expansile osseous lesion involving frontal bones. The patient underwent bi-frontal craniectomy with gross total resection of tumour mass with titanium mesh cranioplasty. His postoperative period was uneventful and was discharged on the seventh postoperative day.
UNASSIGNED: The cases of monostotic skull fibrous dysplasia should be treated by resection of the affected bone and cranioplasty. However, a more conservative re-contouring may be carried out in cases with multifocal involvement or when the excision is considered risky due to proximity to the major venous sinuses.