Craniomaxillofacial Fibro-osseous Lesions in Children.

Craniofacial fibro-osseous lesions represent a diverse spectrum of pathologic conditions where fibrous tissue replaces healthy bone, resulting in the formation of irregular, woven bone. They are more commonly diagnosed in young people, with treatment strategies dependent on clinical behavior and skeletal maturity. This article discusses the examples of craniofacial fibro-osseous lesions, based on the latest classifications, along with their diagnostic criteria and management.

Severe craniofacial fibrous dysplasia associated with decreased visual acuity: a case report.

Fibrous dysplasia is a developmental abnormality characterized by the replacement of normal bone tissue by fibrous connective tissue with poorly organized bone trabeculae. This disorder rarely occurs in the craniofacial region, but in such cases it causes facial asymmetries and has severe clinical implications for the patient. This case report describes the treatment of an 18-year-old man who presented with complaints of facial deformity and decreased visual acuity. Cone beam computed tomography revealed a diffuse bone lesion affecting the region of the maxillary, frontal, and nasal bones on the left side of the face. After microscopic examination, the diagnosis of craniofacial fibrous dysplasia was made. The patient underwent a bilateral temporal craniotomy to perform decompression of the orbital apices and correct the loss of visual acuity. In addition, surgical cosmetic contouring of the facial bones was performed. The patient has been followed up by a multidisciplinary team; at his most recent examination, 18 months after the last surgical intervention, his clinical condition remained stable.

Comparison of the histopathological characteristics of diffuse sclerosing osteomyelitis of the mandible, chronic suppurative osteomyelitis, and craniofacial fibrous dysplasia.

BACKGROUND: There are relatively few reports on the histopathological characteristics of diffuse sclerosing osteomyelitis of the mandible (DSOM), which is difficult to distinguish from chronic suppurative osteomyelitis (CSO) and craniofacial fibrous dysplasia (CFD). This study aimed to summarize and compare the histopathological characteristics of DSOM, CFD, and CSO. MATERIALS AND METHODS: In this study, hematoxylin and eosin-stained sections of patients with DSOM, CSO, and CFD at the Peking University Hospital of Stomatology from 2015 to 2020 were retrieved. The histopathological characteristics were summarized, including new bone formation, inflammatory cell infiltration, bone trabecular morphology, osteoclasts, sequestrum, bacterial mass, and calcified spherules, similar to cementicles. The histopathological characteristics of DSOM, CSO, and CFD were compared, and the results were statistically analyzed. RESULTS: In total, 50, 13, and 10 patients with DSOM, CSO, and CFD were included in this study, respectively. In terms of new bone formation, both DSOM and CSO showed reactive bone formation (p = 1), whereas CFD mainly showed fiber osteogenesis (p < 0.001). The inflammatory cells of DSOM were mainly lymphocytes and plasma cells, whereas those of CSO were mainly lymphocytes and neutrophils (p < 0.001), and there was usually no inflammatory cell infiltration in the CFD specimens (p < 0.001). DSOM, CSO, and CFD showed irregular bone trabeculae (p = 0.045, p = 0.703) and active osteoclasts (p1 = 0.189, p2 = 0.256). DSOM showed a small amount of bacterial mass but no sequestrum; neither of which was found in CFD (p = 1, p = 1), but it was common in CSO (p = 0.011 and p = 0.025). DSOM and CSO showed smooth and regular basophilic lines (p = 0.308), whereas CFD showed a rough and irregular basophilic line (p < 0.001). CONCLUSIONS: The histopathological characteristics of the three diseases were partly similar, but there were evident differences. The main differences are the type of new bone formation, types and distribution of inflammatory cells, and presence of sequestrum and bacterial masses. These differences will help clinicians diagnose DSOM.

Hemorrhagic Fibrous Dysplasia with Acute Neurological Decline: Case Report and Review of the Literature.

BACKGROUND: Fibrous dysplasia is a rare, benign fibro-osseous malformation whose occurrence in the craniofacial area can result in optic nerve compression, a cerebral mass effect, and cosmetic deformity. Most lesions will progress slowly, and the risk of malignant progression is rare. CASE DESCRIPTION: We present the case of a 21-year-old woman who had presented with acute worsening visual loss secondary to hemorrhagic fibrous dysplasia with ensuing optic nerve compression. Emergent surgical decompression resulted in rapid improvement of her visual dysfunction. The pathological features demonstrated a mixed pattern of woven bone in a fibrous background and secondary aneurysmal bone cyst-like changes. CONCLUSIONS: Hemorrhagic transformation of craniofacial FD remains rare but can present with acute neurologic deterioration. Rapid diagnosis and treatment can allow reversal of patient morbidity. We have also included Supplementary Video 1 to illustrate the surgical principles, and we review the reported data of similar cases.

Malignant transformation of craniofacial fibrous dysplasia: a systematic review of overall survival.

The incidence of malignant transformation of fibrous dysplasia (FD) is very rare. Thus, the available knowledge of its characteristics, management, and survival is scarce. Here, we present a systemic review of fibrous dysplasia that had undergone malignant transformation. A comprehensive search was performed on PubMed electronic database. The survival rates and hazard ratios of age, gender, past history of previous radiotherapy, type of FD, and treatment were collected from the published articles and analyzed. Forty-eight cases were eligible for inclusion in the study. Patient's age, gender, past history radiotherapy, and type of FD did not influence the overall survival (OS). The Kaplan Meier analysis showed that the patients who had not received any treatment had poor prognosis with a median survival of 4 months. The patients that received surgery had significantly longer OS than that in the biopsy group. The prognosis of malignant transformation of FD is relatively poor, and surgery is the optimal treatment of choice. Nevertheless, the efficacy of postoperative adjuvant therapy to patient OS is still undefined.

Radiological Imaging Findings of Craniofacial Fibrous Dysplasia.

AIM: To present the radiological findings of fibrous dysplasia (FD) patients who had computed tomography (CT) and/or magnetic resonance imaging (MRI) scans. MATERIAL AND METHODS: This study included a total of 25 patients (17 female and 8 male) who were found to have FD based on CT examinations between March 2010 and July 2018. Involved bones, type of involvement (single or multiple) and CT appearance features (ground-glass, sclerotic, cystic or mixed type) were evaluated. RESULTS: Age range of the patients with FD was 14-55 (mean: 29.92 ± 12.63) years. Sixteen patients had single bone and nine patients had multiple bones affected. Single bone most frequently involved maxillary bones. Multiple bone involvement affected up to four bones, sphenoid bone being the most frequent. Fifteen lesions were mixed type, eight were ground-glass and two were sclerotic on CT. Intense contrast-enhancement was observed in four patients on MRI. CONCLUSION: Craniofacial FD is more frequent in young adults and women, and more commonly involves single bone, mostly maxillary and sphenoid bones. Craniofacial FDs could be of different types on radiological examinations depending upon their compositions.

An Analysis of Clinical and Histopathologic Features of Fibrous Dysplasia of the Jaws: A Series of 40 Cases and Review of Literature.

Fibrous dysplasia (FD) is a rare condition commonly involving the jaws. While FD has a typical clinical and histological presentation, considerable variation exists. Moreover, overlap of features with other disorders is possible. This study serves to characterize the features of a large case series of FD of the jaws. With IRB approval, the University of Florida Oral Pathology Biopsy Service archive was retrospectively searched from 1994 to 2015 for cases of FD. Epidemiological data, location, duration, clinical and radiographic appearance, clinical impression and exact microscopic diagnosis were recorded. The average age was 37.3 years (range 7-87 years) with majority of cases in females (67.5%). The most common ethnicity was Caucasian. Maxillary location was predominant (59%), followed by mandible (38%) and multiple locations (3%). Expansion was reported in 78% of cases. Radiographically, most cases exhibited ground glass opacity, however some presented with a mottled or mixed radiopaque/radiolucent appearance. Histologically, a wide variation in terms of stromal cellularity, presence of osteoblastic rimming, and presence of calcified material mimicking cemento-osseous dysplasia was observed. Clinicians and pathologists should be cognizant of the significant variability in clinical, histopathologic, and radiographic presentation of FD, which may pose a diagnostic challenge.

Displasia cemento-ósea del maxilar: problemas de diagnóstico diferencial a propósito de un caso / Differential diagnosis of cemento-osseous dysplasia of the maxilla. A case report

La displasia cemento-ósea es una lesión frecuente que afecta a los maxilares y no exige tratamiento intensivo. Su principal interés radica en el riesgo de confusión con entidades de comportamiento más agresivo, como los fibromas osificantes y cementificantes, que exigen tratamiento. No existen unos claros criterios de diagnóstico diferencial histopatológico entre ambas entidades. En este trabajo presentamos el caso de un niño de 13 años al que se realizó una biopsia de una lesión en el maxilar, sin diagnóstico clínico de sospecha. El estudio histológico revela un tejido fibroso poco celular en el seno del cual se observan trabéculas óseas sin ribete de osteoblastos y cúmulos de cemento. Nuestro diagnóstico final fue displasia cemento-ósea. Se muestran los principales rasgos de la lesión y se analizan los criterios que pueden ayudar al difícil diagnóstico diferencial de esta entidad

Cemento-osseous dysplasia is a benign lesion which affects the jaw bones. It is a frequent incidental finding but no aggressive therapy is necessary. However, it may be confused with more aggressive entities, such as ossifying and cementifying fibroma, which do require treatment. There are no clear-cut histopathological criteria to differentiate between these entities. We present a case of a 13-year old boy who underwent a biopsy of a clinically undiagnosed maxillary lesion. Histopathological analysis revealed moderately cellular fibrous tissue with bone trabeculae with no osteoblastic rimming and clusters of intensely basophilic material corresponding to cementum. The final diagnosis was cemento-osseus dysplasia. The main histopathological features important in the distinction of these entities are discussed

Multi-analytic study of a probable case of fibrous dysplasia (FD) from certosa monumental cemetery (Bologna, Italy).

OBJECTIVE: To evaluate, via a multidisciplinary approach, a distinctive paleopathological condition believed to be fibrous dysplasia, found on a 19th/20th century skeleton from Certosa Monumental Cemetery, Bologna, Italy. MATERIALS: A skeletonized cranium and mandible recovered from an ossuary in 2014. METHODS: Pathological alterations were analysed by radiological examination, dental macrowear, histopathological and genetic analyses. RESULT: The skeleton is believed to be an adult male. Differential diagnoses include Paget's disease, McCune-Albright syndrome, osteochondroma and osteosarcoma. The radiographic findings, along with the solitary nature of the lesions, are strong evidence for the diagnosis of fibrous dysplasia (FD). Genetic analysis further revealed a frequency of ˜1% of mutant alleles with the R201C substitution, one of the post-zygotic activating mutation frequently associated with FD. CONCLUSIONS: The multi-analytical method employed suggests a diagnosis of monostotic form of FD. The diagnostic design incorporates multiple lines of evidence, including macroscopic, histopathological, and genetic analyses. SIGNIFICANCE: Through the use of a multi-analytic approach, robust diagnoses can be offered. This case serves as one of the oldest examples of FD from an historical context. The genetic mutation detected, associated with FD, has not been previously reported in historical/ancient samples.

Fibrous dysplasia of the jaws: Integrating molecular pathogenesis with clinical, radiological, and histopathological features.

Fibrous dysplasia is a non-neoplastic developmental process that affects the craniofacial bones, characterized by painless enlargement as a result of bone substitution by abnormal fibrous tissue. Postzygotic somatic activating mutations in the GNAS1 gene cause fibrous dysplasia and have been extensively investigated, as well as being helpful in the differential diagnosis of the disease. Fibrous dysplasia may involve one (monostotic) or multiple bones (polyostotic), sporadically or in association with McCune-Albright syndrome, Jeffe-Lichenstein syndrome, or Mazabreud syndrome. This review summarizes the current knowledge on fibrous dysplasia, emphasizing the value of integrating the understanding of its molecular pathogenesis with the clinical, radiological, and histopathological features. In addition, we address important aspects related to the differential diagnosis and patient management.

Cystic Degeneration of Craniofacial Fibrous Dysplasia.

BACKGROUND: Fibrous dysplasia (FD) is most often a slowly progressive benign disease in which the normal bone structure is replaced by fibrous and osteoid tissue. CASE DESCRIPTION: A 16-year-old adolescent, known with FD in the sphenoid bone, suffered an acute decreased visual acuity with papilledema on the left eye. The radiologic images were best compatible with cystic degeneration of the known FD with optic nerve compression in the optic canal. Decompression of the optic nerve was performed through an endoscopic exploration of the left sphenoid sinus. The visual acuity recovered completely. CONCLUSIONS: In FD with cystic changes, leading to acute signs of optic nerve compression, early aggressive surgical decompression is strongly recommended. Cystic degeneration of the FD, although rare, should be considered.

Infratemporal fossa tumors: When to suspect a malignant tumor? A retrospective cohort study of 62 cases.

OBJECTIVES: Infratemporal fossa (ITF) tumors are rare and little is known about their general epidemiology, making it sometimes difficult for clinicians, who seldom encounter them, to distinguish between benign and malignant forms on the basis of the initial clinical and radiological work-up alone. The objectives of this retrospective study were: (i) to determine the respective prevalences of the various histologic types of ITF tumor, and (ii) to assess associations between certain clinical and radiological features and malignancy. METHODS: A single-center observational study in a university hospital included all new consecutive cases of ITF tumor treated from January 2000 to December 2016. Histologic type, demographics, clinical presentation and imaging findings were analyzed. RESULTS: In total, 62 patients were included. 74% of tumors were benign (n=46) and 26% malignant. Juvenile nasopharyngeal angiofibroma, adenoid cystic carcinoma and schwannoma were the most frequent histologic types, accounting for 47%, 16% and 10% of cases, respectively. The only clinical or imaging signs significantly associated with malignancy were trismus, facial pain, facial hypoesthesia and neural invasion on magnetic resonance imaging (all P-values<0.05). CONCLUSION: This study provides general epidemiological data on ITF tumors, and identified several clinical and radiologic signs to help clinicians suspect malignancy.

Fibrous dysplasia imitating malignancy.

Fibrous dysplasia is a benign bone disease, presenting as monostotic or polyostotic lesions, or as part of a syndrome (McCune-Albright/Mazabraud). Its clinical course shows a variegated picture and the progression of its growth is unpredictable. In the workup of 39 fibrous dysplasia cases in the cranio-facial area, four cases presented fast growth tendencies, of which two patients with McCune-Albright syndrome showed malignant-like rapid growth. This local aggressive form is extremely rare, and the concept of this issue has not been clearly defined. With regard to the speed of growth a volumetric-time analysis in one of our cases demonstrated a 74 days tumor doubling rate with an exponential growth curve. According to the literature the aggressive form presented extra-cranially mainly at an adult age, whereas its appearance in our cranio-facial patient collective was much younger. Distinguishing nonmalignant and malignant aggressive forms is difficult and highly inconsistent in the literature. We therefore implemented a quantitative growth measure analysis to define aggressive forms based on progression and speed of growth and impartial of type of FD, localization or functional incapacity. Due to our study findings and literature review we state a prevalence of an aggressive form might be possibly about 5 %.

Abordagem cirúrgica no tratamento da displasia fibrosa craniofacial- experiência de 14 anos / Surgical approach to the treatment of craniofacial fibrous dysplasia - A 14-year experiencedysplasia - 14 years experience

INTRODUÇÃO: Dentre os tumores benignos do esqueleto craniofacial, a displasia fibrosa caracteriza-se pelo crescimento progressivo e acometimento de jovens, acarretando deformidade funcional e estética. Esse trabalho analisa aspectos clínicos e prognósticos de pacientes com essa patologia, submetidos a tratamento cirúrgico. MÉTODOS: Análise retrospectiva de 19 pacientes com displasia fibrosa craniofacial, acompanhados de janeiro de 1997 a dezembro de 2011, tratados com remodelamento ósseo e ressecção cirúrgica. Revisão da literatura sobre. RESULTADOS: A distribuição etária variou de 8 a 65 anos, com média de 21,75 anos. Dez pacientes (52,7%) eram do sexo feminino. A forma poliostótica predominou, com 15 casos (78,9%). Entre os ossos acometidos destacaram-se esfenóide, etmóide e frontal, nas formas poliostóticas; e maxila e zigoma, nas monostóticas. A principal queixa foi de assimetria da face. Um paciente evoluiu com diminuição de acuidade visual. O tratamento baseou-se na ressecção cirúrgica e reconstrução com enxerto, quando doença localizada, e no desgaste e remodelamento ósseo, em formas poliostóticas. Em apenas um caso (5,2%), com compressão de nervo óptico, foi necessário acesso intracraniano. Reabordagem cirúrgica, por crescimento tumoral, foi necessária em três pacientes. Como complicações, tivemos um caso de lagoftalmo e epicanto no pós-operatório de paciente tratado por cirurgia com acesso infraorbitário. Ausência de outras intercorrências no seguimento a curto e longo prazo. Os resultados de preservação de função e recuperação de contorno facial foram satisfatórios. CONCLUSÃO: Essa experiência, em concordância com a literatura, permite concluir que a cirurgia é eficaz na abordagem de casos selecionados de displasia fibrosa craniofacial.

INTRODUCTION: Fibrous dysplasia is benign tumor of the craniofacial skeleton that primarily affects young patients. It is characterized by the progressive growth of benign fibrous tumors with resulting functional and aesthetic deformities. This study assesses the clinical and prognostic features in patients with fibrous dysplasia who underwent surgical treatment at our institution. METHODS: Retrospective analysis of 19 patients with craniofacial fibrous dysplasia, treated between January 1997 and December 2011 with bone remodeling and surgical resection. We also review the literature regarding fibrous dysplasia. RESULTS: Patients ranged between 8-65 years old, with a mean age of 21.75 years. Ten patients (52.7%) were women. The polyostotic form was predominant and present in15 cases (78.9%). The sphenoid, ethmoid, and frontal bones were most commonly involved in the polyostotic form and the mandibular and zygomatic bones were most commonly involved in the monostotic form. The main complaint was asymmetry of the face. One patient developed decreased visual acuity. Treatment was based on surgical resection and graft reconstruction in the localized form of the disease, and bone abrasion and remodeling in the polyostotic form. Intracranial access was necessary in only one case (5.2%) where the optic nerve was compressed. Repeat surgical treatment due to recurrent tumor growth was necessary in three patients. The only complication occurred in a patient who developed lagophthalmos and epicanthus postoperatively after undergoing surgery using infraorbital access. No other complications occurred during short- and long-term follow-up. Functional preservation and facial contour recovery outcomes were satisfactory. CONCLUSION: Our experience, along with that of other investigators, demonstrates that surgery is effective in treating selected cases of craniofacial fibrous dysplasia.