Increased Prevalence of Malignancies in Fibrous Dysplasia/McCune-Albright Syndrome (FD/MAS): Data from a National Referral Center and the Dutch National Pathology Registry (PALGA).

Malignant transformation of fibrous dysplasia lesions has been reported in patients with fibrous dysplasia/McCune-Albright syndrome (FD/MAS). Recently, we have observed an increased risk for breast cancer. In this study, the prevalence of skeletal and extraskeletal malignancies in patients with FD/MAS in the Netherlands was assessed by analyzing data from our cohort of FD/MAS patients, the Dutch Pathology Registry (PALGA), and the Netherlands Cancer Registry (NCR). We extracted data on sex, age at diagnosis of FD/MAS, type of FD/MAS, type of malignancy, and age at diagnosis of malignancy and histology of bone and malignant tissue when available, including GNAS-mutation analysis from patients' medical records. Standardized Morbidity Ratios (SMRs) with 95% confidence intervals were calculated. Twelve malignancies were identified in the LUMC FD/MAS cohort and 100 in the PALGA cohort. In this cohort, SMR was increased for osteosarcoma (19.7, 95% CI 3.5-48.9), cervical cancer (4.93, 95%CI 1.7-8.2), thyroid cancer (3.71, 95% CI 1.1-7.8), prostate cancer (3.08, 95% CI 1.8-4.6), and melanoma (2.01, 95%CI 1.2-3.1). SMRs for pancreatic cancer or hepatocellular carcinoma could not be calculated due to low numbers. The small number of malignancies identified in our FD/MAS cohort precluded the calculation of SMRs for our cohort specifically. Our findings show that patients with FD/MAS appear to have an increased risk for osteosarcoma, cervical, thyroid, and prostate cancer and melanoma. However, these data should be interpreted with caution, as true incidence rates of the identified malignancies may be influenced by the inclusion of only patients with histologically confirmed FD/MAS. The etiology of this increased risk for malignancies still needs to be elucidated.

Natural History and Progression of Craniofacial Fibrous Dysplasia: A Retrospective Evaluation of 114 Patients From Massachusetts General Hospital.

PURPOSE: The natural history of fibrous dysplasia (FD) is poorly understood. The purpose of this study was to identify differences in demographic, clinical, and radiographic characteristics among patients with craniofacial FD, including McCune-Albright syndrome (MAS), polyostotic fibrous dysplasia (PFD), and monostotic fibrous dysplasia (MFD). We hypothesized that patients with MAS would show higher disease severity, have more complications, and undergo more operations than those with PFD or MFD. PATIENTS AND METHODS: A retrospective cohort study of patients with MAS or FD, evaluated at Massachusetts General Hospital from 2000 to 2018, was implemented. Patients of all ages and genders were identified through Massachusetts General Hospital Data Registries using International Classification of Diseases, Ninth Revision (ICD-9) and International Classification of Diseases, Tenth Revision (ICD-10) codes. Those with adequate clinical and radiographic data were included. Predictor variables were diagnosis of MAS, PFD, or MFD; age; and gender. Outcome variables included severity of disease at initial presentation (aggressive, nonaggressive and slow growing, or quiescent), number of operations, and complications: pain, sensory disturbances, pathologic fracture, airway obstruction, osteomyelitis, and dental findings. Data were analyzed with descriptive statistics and assessed for significance using χ2 tests and analysis of variance (P < .05). RESULTS: A total of 229 patients were identified: 114 had craniofacial FD, and 70 of these 114 (61.4%) met the inclusion criteria (48 of whom were female patients). The average age at diagnosis was 23.5 years; mean length of follow-up, 5.8 years. Diagnoses included MAS in 9 patients, PFD in 24, and MFD in 37. Signs and symptoms at initial presentation were pain (n = 29), sensory abnormalities (n = 13), facial deformity or swelling (n = 54), and dental findings (n = 25). At presentation, the biological behavior of disease was 77.8% aggressive, 11.1% nonaggressive, and 11.1% quiescent in the MAS group; 41.7%, 41.7%, and 16.7%, respectively, in the PFD group; and 29.7%, 29.7%, and 40.5%, respectively, in the MFD group. Patients with MAS were younger and were more likely to have pain, pathologic fractures, more bones involved, bilateral disease, and visual symptoms than those with PFD or MFD. MAS patients underwent more operations (mean, 4.2 ± 4.18) than those with PFD (mean, 2.6 ± 2.31; P = not significant) or MFD (mean, 1.7 ± 1.28; P = .010). CONCLUSIONS: The results of this study indicate that patients with MAS, presumably with the same mutation, are more likely to have aggressive disease, complications, and more operations than those with PFD or MFD.

Prevalence of Different Forms and Involved Bones of Craniofacial Fibrous Dysplasia.

BACKGROUND: The purposes of this study were to analyze the prevalence of various craniofacial bones involved in patients with craniofacial fibrous dysplasia (CFD) and to demonstrate the most common form and bone involvement in patients with CFD for surgeons. METHODS: To address the research purpose, the authors designed and performed a systematic review with meta-analysis. A comprehensive electronic search without date was performed in August 2013. Data extracted from the previously published literature were analyzed with STATA 11.0 software. RESULTS: Relevant data were extracted from 18 studies (487 total participants) and revealed that in CFD patients, the prevalence of the monostotic type was 56% (95% confidence intervals [CI]: 0.42-0.70; P = 0.000) and polyostotic type was 47% (95% CI: 0.31-0.63; P = 0.000); McCune-Albright syndrome was a relatively rare form (7%; 95% CI: 0.02-0.12; P = 0.006). Subgroup analyses indicated that the maxilla was most commonly involved (28%; 95% CI: 0.42-0.70; P = 0.000) in monostotic CFD, followed by the orbital (27%; 95% CI: -0.23-0.76; P = 0.298), mandibular (25%; 95% CI: 0.16-0.35; P = 0.000), frontal (22%; 95% CI: 0.09-0.34; P = 0.001), and temporal bones (12%; 95% CI: 0.03-0.21; P = 0.012). The prevalence of maxilla involvement in polyostotic CFD patients was as high as 30% (95% CI: 0.18-0.42; P = 0.000). CONCLUSION: This meta-analysis found that monostotic and polyostotic forms of CFD shared similar prevalence rates. Furthermore, the maxilla was found to be the most commonly involved bone in both monostotic and polyostotic CFD.

Surgical treatment of craniofacial fibrous dysplasia in adults.

Craniofacial fibrous dysplasia (FD) is a rare disorder that may require neurosurgical expertise for definitive management; however, surgical management of FD in adult patients is uncommon. Although other therapies have been shown to slow progression, the only definitive cure for adult craniofacial FD is complete resection with subsequent reconstruction. The authors review the biological, epidemiologic, clinical, genetic, and radiographic characteristics of adult FD, with an emphasis on surgical management of FD. They present a small series of three adult patients with complex FD that highlights the surgical complexity required in some adult patients with FD. Because of the complex nature of these adult polyostotic craniofacial cases, the authors used neurosurgical techniques specific to the different surgical indications, including a transsphenoidal approach for resection of sphenoidal sinus FD, a transmaxillary approach to decompress the maxillary branch of the trigeminal nerve with widening of the foramen rotundum, and complete calvarial craniectomy with cranioplasty reconstruction. These cases exemplify the diverse range of skull base techniques required in the spectrum of surgical management of adult FD and demonstrate that novel variations on standard neurosurgical approaches to the skull base can provide successful outcomes with minimal complications in adults with complex craniofacial FD.

Incidence and Prevalence of Fibrous Dysplasia/McCune-Albright Syndrome: A Nationwide Registry-Based Study in Denmark.

CONTEXT: Fibrous dysplasia/McCune-Albright syndrome (FD/MAS) is a rare genetic disorder. Incidence and prevalence are not well-studied. Epidemiological research is complicated by the rarity of FD/MAS, absence of registries, heterogeneous presentation, and possibly asymptomatic phenotype. FD/MAS may present with FGF23-mediated hypophosphatemia, of which the epidemiology is also unclear. OBJECTIVE: Evaluate incidence and prevalence of FD/MAS and FD/MAS-related hypophosphatemia. METHODS: This cohort study based on the nationwide Danish National Patient Registry from 1995-2018, included patients identified by ICD-10 codes M85.0 (monostotic FD [MFD]) and Q78.1 (polyostotic FD [PFD]/MAS). Incidence rates and prevalence were calculated and stratified by sex, age, calendar period, and diagnosis code. Cases were screened for FD-associated hypophosphatemia by diagnosis code E.83 (disorder of mineral metabolism) and dispatched vitamin D analogues. RESULTS: A total of 408 patients were identified, 269 with MFD (66%), 139 with PFD/MAS (34%), comparable between sexes. Incidence of FD/MAS demonstrated increasing secular trend with a rate of 3.6 per 1 000 000 person-years (95% CI: 2.9, 4.5) in 2015-2018. Incidence peaked between age 11 and 20. Prevalence of FD/MAS increased over time to 61.0 (95% CI: 54.6, 67.4) per 1 000 000 persons in 2018. The incidence rate of MFD was 1.5-fold that of PFD/MAS in the first decade, rising to 2.5-fold in the last decade. No FD/MAS cases were registered with diagnosis code or treatment for hypophosphatemia. CONCLUSION: FD/MAS is rare, diagnosis peaks during adolescence without sex predominance, and MFD is most prevalent. Hypophosphatemia may be underdiagnosed and undertreated, or it may be underregistered, comparing this study to literature.

Spontaneous malignant transformation in craniomaxillofacial fibrous dysplasia.

Spontaneous malignant transformation in craniomaxillofacial fibrous dysplasia (FD) is extremely rare and its clinicopathological characteristics remain largely unknown. Here, we aimed to characterize the epidemiology and clinicopathological features of malignancies arising from preexisting FD by presenting data from a Chinese tertiary referral hospital and review of English and Chinese literatures. The craniomaxillofacial disease registry of Shanghai Ninth People's Hospital was searched and reviewed to collect relevant information for patients diagnosed as malignant transformation in craniomaxillofacial FD between January 1993 and December 2010. An English and Chinese literature review was conducted to retrieve pertinent cases published in the past 2 decades with preset inclusion criteria. All included cases were further analyzed with regard to associated clinical and pathological variables. Three cases with osteosarcoma arising from previous craniomaxillofacial FD were found at our institution and 35 other cases were identified by literature review. These uncommon entities usually occurred in adults with a mean age of 39.8 years and equal gender preponderance. Maxilla remained the most common sites for malignancies followed by mandible and zygoma. Most malignancies were diagnosed as osteosarcoma followed by fibrosarcoma, chondrosarcoma, and malignant fibrous histiocytoma. Radical resection alone or with postoperative radiotherapy/chemotherapy remains the main treatment strategy with unfavorable prognosis due to local recurrence and distant metastasis. Taken together, our findings might for the first time provide the comprehensive information regarding the epidemiology, clinicopathological features, treatment, and prognosis of malignancies in craniomaxillofacial FD. Further investigations are warranted to improve early diagnosis and proper treatment for these uncommon entities.

Value of rare diseases reference centers: impact on diagnosis and access to specialized care in fibrous dysplasia of bone.

INTRODUCTION: Reference Centers and Rare Disease Health Networks aim to improve the management of patients with rare diseases. The French reference center for Fibrous Dysplasia was certified in 2006. OBJECTIVE: The objective of our study was to assess the effectiveness of our reference center since its constitution. METHODS: In a retrospective cohort study, we compared the activity of our center, including the time elapsed between access to the center and the diagnostic delay of patients with Fibrous Dysplasia between two periods, 1994-2006 (before certification) and 2007-2019 (after certification). Data were extracted from patients' records (Easily®). Wilcoxon and Fisher tests were performed, using R®. RESULTS: Our cohort included 527 patients with Fibrous Dysplasia/Mc Cune Albright syndrome. The activity of the Fibrous Dysplasia center increased from 139 patients in the first period (1994-2006) to an additional 388 patients for the second period (2007-2019). Mean time elapsed to diagnosis of Fibrous Dysplasia was 1.5 years before 2007 and 1.9 years after 2007 (p = 0.12). Diagnosis was made before referral in over 80% of patients. There was a non-significant decrease in the number of patients with delayed diagnosis: 37 patients (44%) in the first period had a diagnostic delay and 94 patients (33%) in the second period (p = 0.07). Patients were referred to our center on average 6.8 years (before 2007) and 7.9 years (after 2007) after their diagnosis (p = 0.77). CONCLUSION: Healthcare organization with reference centers significantly impacted the management of patients with Fibrous Dysplasia/Mc Cune Albright syndrome, with a substantial increase in the activity of our center, that roughly tripled since certification. This healthcare organization was also associated with a trend toward decreasing diagnostic delay. However, diagnostic delay affected more than a third of patients and the time to access to the center remained extended (≈7-8 years after diagnosis). The current challenge lies in informing primary care providers and patients about education to rare diseases and existence of reference centers for earlier and more effective specialized management.

Coxa Vara Deformity in Fibrous Dysplasia/McCune-Albright Syndrome: Prevalence, Natural History and Risk Factors: A Two-Center Study.

This study aimed to evaluate the prevalence of and risk factors for coxa vara deformity in patients with fibrous dysplasia/McCune-Albright syndrome (FD/MAS). This study was conducted at the National Institutes of Health and Leiden University Medical Center. All patients with any subtype of FD/MAS, FD involving the proximal femur, one or more X-rays available and age <30 years were included. X-rays were scored for the neck-shaft angle (NSA). Varus deformity was defined as NSA <110 degrees or >10 degrees below age-specific values. Risk factors for deformity were assessed by nested case-control analysis, comparing patients and femurs with and without deformity, and by linear mixed effects model, modeling temporal NSA decrease (the natural course of the NSA) in non-operated femurs with two or more X-rays. Assessed variables included growth hormone excess, hyperthyroidism, hypophosphatemia, >25% of the femur affected, calcar destruction, radiolucency, and bilateral involvement. In total 180 patients were studied, 57% female. Mean ± SD baseline age was 13.6 ± 7.5 years; median follow-up 5.4 (interquartile range [IQR], 11.1) years. Sixty-three percent (63%) were diagnosed with MAS. A total of 94 patients were affected bilaterally; 274 FD femurs were analyzed; 99 femurs had a varus deformity (36%). In the nested case-control analysis, risk factors were as follows: presence of MAS (p < 0.001), hyperthyroidism (p < 0.001), hypophosphatemia (p < 0.001), high percentage of femur affected (p < 0.001), and calcar destruction (p < 0.001). The linear mixed effects model included 114 femurs, identified risk factors were: growth hormone excess (ß = 7.2, p = 0.013), hyperthyroidism (ß = 11.3, p < 0.001), >25% of the femur affected (ß = 13.2, p = 0.046), calcar destruction (ß = 8.3, p = 0.004), radiolucency (ß = 3.9, p = 0.009), and bilateral involvement (ß = 9.8, p = 0.010). Visual inspection of the graph of the model demonstrated most progression of deformity if NSA <120 degrees with age < 15 years. In conclusion, in tertiary care centers, the prevalence of FD/MAS coxa vara deformity was 36%. Risk factors included presence of MAS, high percentage of femur affected, calcar destruction, radiolucency, NSA <120 degrees and age < 15 years. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Paget's disease of bone: analysis of 134 cases from an island in Southern Brazil: another cluster of Paget's disease of bone in South America.

Paget's disease of bone (PDB) exhibits a marked geographic variation. In Brazil, the prevalence of PDB is unknown and only a few clinical data are available. The aim is to determine clinical, laboratory, imaging and response to treatment data in a large PDB case series in the city of Florianopolis, Brazil. We have performed a retrospective study based on charts reviews of all patients with PDB followed at the University Hospital of the Federal University of Santa Catarina and at five different private rheumatology outpatient offices in Florianopolis, between 1995 and 2009. One hundred and thirty-four patients with PDB were identified. Mean age at diagnosis was 63.2 ± 10.5 years, 67.2% were women, and 91.1% were Caucasian. Positive family history was reported in only 8.2%. Polyostotic disease was found in 75.0% of the cases, bone pain in 77.9%, and bone deformities in 15.9%. Higher levels of AP were significantly associated with polyostotic disease and skull involvement. Pelvic bones were the most frequently affected (53.7%). Complications included deafness in 8.2%, bone fractures in 3.0%, hydrocephalus in 2.2%, and cauda equina syndrome in 0.7% of the cases. Treatment with zoledronic acid achieved the best response with only 2.9% failing to respond adequately. According to literature data, PDB in South America seems to be characterized by an overall low prevalence, but with localized clusters with higher prevalence. The authors have described a cluster of PDB in Florianopolis, in Southern Brazil. Further properly designed studies are necessary to clarify the PDB epidemiology in South America.

Neuropathic-like Pain in Fibrous Dysplasia/McCune-Albright Syndrome.

CONTEXT: Pain is a major symptom in adults with fibrous dysplasia/McCune-Albright syndrome (FD/MAS) and response to current treatments, including bisphosphonates and standard analgesics (nonsteroidal anti-inflammatory drugs and opiates) is unpredictable. No studies have explored whether the type of pain is variable in this patient group. OBJECTIVE: To determine the frequency of neuropathic-like pain in patients with FD/MAS. DESIGN: Retrospective, dual registry study. SETTING: Community. PATIENTS: FD/MAS online registries: the US-based Familial Dysautonomia Foundation (FDF) and the UK-based Rare and Undiagnosed Diseases (RUDY) study. INTERVENTION: Subjects completed questionnaires to evaluate the presence of features of neuropathic-like pain (painDETECT) and the impact on sleep quality (Pittsburgh Sleep Quality Index) and mental health (Hospital Anxiety and Depression Scale). Descriptive statistics were used to characterize the prevalence and associated burden of neuropathic-like pain. MAIN OUTCOME MEASURES: Incidence of neuropathic, nociceptive, and unclear pain. RESULTS: Of 249 participants, one third experienced neuropathic-like pain. This group had statistically significantly (P < 0.001) worse mental well-being and sleep in comparison to those with predominately nociceptive pain. CONCLUSIONS: Neuropathic-like pain is common in patients with FD/MAS and associated with worse quality of life. Evaluation of pain in patients with FD/MAS should include assessment of neuropathic-like pain to guide personalized approaches to treatment and inform future research.

Risk of developing spontaneous MRONJ in fibrous dysplasia patients treated with bisphosphonates: a systematic review of the literature.

OBJECTIVE: The objective of this systematic review was to evaluate the risks of medication-related osteonecrosis of the jaw (MRONJ) in fibrous dysplasia (FD) and McCune-Albright syndrome (MAS) patients treated with bisphosphonates. METHOD AND MATERIALS: A systematic review of the literature was performed by searching PubMed and Embase databases using MeSH terms (fibrous dysplasia of bone, "fibrous dysplasia, polyostotic," osteonecrosis, jaw, therapeutics, diphosphonates, denosumab, teriparatide, estrogens, hormones, raloxifene hydrochloride, calcitonin, cathepsin K) and non-MeSH terms (antiresorptive therapy, antiresorptives, bisphosphonate, estrogen therapy, hormone therapy, bazedoxifene, cathepsin K inhibitor). Articles were limited to human studies, in English language, in which patients were on antiresorptives for at least 1 year. PRISMA statement guidelines were used to eliminate non-relevant studies. The PICOT question asked was, "Does exposure to bisphosphonates and other antiresorptives cause occurrence of MRONJ in fibrous dysplasia and fibrous dysplasia/McCune-Albright syndrome patients followed up for at least 1 year?" RESULTS: Eight eligible articles were included in the quantitative synthesis after articles were screened using a PRISMA flowchart. There were 12 reported occurrences of MRONJ among a combined total of 312 fibrous dysplasia and fibrous dysplasia/McCune-Albright syndrome patients (3.85%). CONCLUSION: Patients with fibrous dysplasia or fibrous dysplasia/McCune-Albright syndrome have a low incidence of MRONJ and may apparently have low susceptibility to spontaneous development of MRONJ.

Long Bone Fractures in Fibrous Dysplasia/McCune-Albright Syndrome: Prevalence, Natural History, and Risk Factors.

Fibrous dysplasia/McCune-Albright syndrome (FD/MAS) is a rare bone and endocrine disorder arising along a broad spectrum. Long-bone fractures are a common, painful, and potentially disabling complication. However, fracture prevalence and risk factors have not been well-established, making it difficult to predict which patients are at risk for a severe course. Clinical and imaging data were reviewed from two large, well-phenotyped cohorts (National Institutes of Health [NIH] in the United States and the Leiden University Medical Center [LUMC] in the Netherlands) to identify long-bone fractures at FD sites. Skeletal burden score was quantified using bone scintigraphy. Multiple linear regressions were performed to identify clinical associations with fractures. A total of 419 patients were included (186 NIH, 233 LUMC); 194 (46%) had MAS endocrinopathies. Median age at last follow-up was 30.2 years (range 3.2-84.6, interquartile range [IQR] 25.5), and median skeletal burden score was 16.6 (range 0-75, IQR 33). A total of 48 (59%) patients suffered one or more lifetime fracture (median 1, range 0-70, IQR 4). Median age at first fracture was 8 years (range 1-76, IQR 10). Fracture rates peaked between 6 and 10 years of age and decreased thereafter. Lifetime fracture rate was associated with skeletal burden score (ß = 0.40, p < 0.01) and MAS hyperthyroidism (ß = 0.22, p = 0.01). Younger age at first fracture was associated with skeletal burden score (ß = -0.26, p = 0.01) and male sex (ß = -0.23, p = 0.01). Both skeletal burden score >25 and age at first fracture ≤7 years were associated with a higher total number of lifetime fractures (median 4, range 1-70, IQR 5 versus median 1, range 1-13, IQR 1) (p < 0.01). In conclusion, higher skeletal burden score and MAS hyperthyroidism are associated with long-bone fractures in FD/MAS. Both skeletal burden score ≥25 and age at first fracture ≤7 years are associated with a higher lifetime long-bone fracture risk and may predict a more severe clinical course. These results may allow clinicians to identify FD/MAS patients at risk for severe disease who may be candidates for early therapeutic interventions. © 2021 American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Prevalence of Polycystic Ovary Syndrome in Patients With McCune Albright Syndrome.

STUDY OBJECTIVE: To identify polycystic ovarian syndrome (PCOS) in a population of female patients with McCune-Albright syndrome (MAS) by retrospective chart review. DESIGN: Retrospective study. SETTING: Academic setting. PARTICIPANTS: All female patients with a prior diagnosis of MAS who were more than 12 years of age at the time of chart review. Only complete medical records from January 2009 to January 2020 were included in the analysis. INTERVENTIONS: None. MAIN OUTCOME MEASURE(S): Diagnosis of PCOS based on the Rotterdam 2003 criteria. RESULTS: Seventeen female patients with MAS were included in the analysis. PCOS appeared to be more prevalent in MAS patients than expected based on population estimates (exact binomial test = 0.353; CI = 0.142-0.617, P = .01). The average body mass index was not significantly different between MAS patients with and without PCOS (23.38 kg/m2 vs 23.44 kg/m2, 2-sample Wilcoxon rank-sum test with continuity correction, W = 29, P = 0.733). The majority of patients (71%) were treated with an aromatase inhibitor and/or a gonadotropin-releasing hormone (GnRH) agonist. CONCLUSIONS: The results of this study suggest that female individuals with MAS have a statistically higher prevalence of PCOS. These findings warrant further studies to determine whether the increased risk of PCOS may be associated with precocious puberty, treatment of precocious puberty, or other factors.

Fibrous dysplasia & McCune-Albright syndrome: an experience from a tertiary care centre in north India.

BACKGROUND & OBJECTIVES: Fibrous dysplasia (FD) is a rare metabolic bone disease and information available from India is limited to only anecdotal case reports. We describe the clinical profile and therapeutic outcome of 25 patients with FD observed over a period of 14 yr in a tertiary care centre from north India. METHODS: In this retrospective study patients (n = 25) with diagnosis of fibrous dysplasia based on either classical radiological features and/or histological evidence on bone biopsy, were analyzed. Associated endocrinopathies if any, were evaluated. The diagnosis of McCune Albright syndrome (MAS) was considered when fibrous dysplasia was accompanied by either café-au-lait macules and/or endocrinopathies. The clinical presentation, biochemical parameters and imaging were analysed. Seven patients received bisphosphonate therapy. The final outcome and side effects were noted. RESULTS: Age of the patients ranged from 7 to 48 yr (mean ± SD, 24.2 ± 11.4 yr) with a lag time between onset of symptoms and presentation ranging from 1 to 20 yr (mean ± SD, 6.6 ± 6.2 yr). The mean duration of follow up was 3.5 ± 2.1 yr. Eighteen (72%) patients had polyostotic disease while the remaining had monostotic FD. Eight patients had endocrinopathies: five had acromegaly, one each had gonadotropin independent precocious puberty (GIPP), hyperthyroidism and hypophosphatemic rickets. One child with GIPP later developed hyperthyroidism. McCune Albright syndrome was observed in 10 (40%) patients. A majority of the patients underwent various minor or major surgical procedures and seven patients received bisphosphonates for recurrent pathological fractures. Bone pain was reduced in all bisphosphonate treated patients with a decrease in subsequent fractures. INTERPRETATION & CONCLUSIONS: This series of FD patients from north India shows the varying presentations of this rare disease. Medical treatment with bisphosphonates appears to be potentially rewarding.

Genotype-Phenotype Correlation in Fibrous Dysplasia/McCune-Albright Syndrome.

CONTEXT: Fibrous dysplasia/McCune-Albright syndrome (FD/MAS) is a rare bone and endocrine disorder resulting in fractures, pain, and disability. There are no targeted or effective therapies to alter the disease course. Disease arises from somatic gain-of-function variants at the R201 codon in GNAS, replacing arginine by either cysteine or histidine. The relative pathogenicity of these variants is not fully understood. OBJECTIVE: This work aimed 1) to determine whether the most common GNAS variants (R201C and R201H) are associated with a specific clinical phenotype, and 2) to determine the prevalence of the most common GNAS variants in a large patient cohort. METHODS: This retrospective cross-sectional analysis measured the correlation between genotype and phenotype characterized by clinical, biochemical, and radiographic data. RESULTS: Sixty-one individuals were genotyped using DNA extracted from tissue or circulating cell-free DNA. Twenty-two patients (36.1%) had the R201C variant, and 39 (63.9%) had the R201H variant. FD skeletal disease burden, hypophosphatemia prevalence, fracture incidence, and ambulation status were similar between the 2 groups. There was no difference in the prevalence of endocrinopathies, ultrasonographic gonadal or thyroid abnormalities, or pancreatic involvement. There was a nonsignificant association of cancer with the R201H variant. CONCLUSION: There is no clear genotype-phenotype correlation in patients with the most common FD/MAS pathogenic variants. The predominance of the R201H variant observed in our cohort and reported in the literature indicates it is likely responsible for a larger burden of disease in the overall population of patients with FD/MAS, which may have important implications for the future development of targeted therapies.

[Myopia in systemic disorders]. / Krótkowzrocznosc w schorzeniach ogólnoustrojowych.

Myopia is the most common refractive error Myopia has been well established as a multifactorial disease with both genetic and environmental etiology. A number of genetic loci have been linked with myopia. We have described the prevalence and the symptoms of systemic disorders associated with myopia, including: Stickler syndrome, Marfan syndrome, Ehlers-Danlos syndrome, Weill-Marchesani syndrome, homocystinuria, McCune-Albright syndrome, Kniest syndrome, Down syndrome, Prader-Willi syndrome, Noonan syndrome, Cohen syndrome, Rubinstein-Taybi syndrome, Cornelia de Lange syndrome and fetal alcohol syndrome.

Prevalence and Clinical Features of Mazabraud Syndrome: A Multicenter European Study.

BACKGROUND: Mazabraud syndrome is a rare disorder, characterized by the presence of fibrous dysplasia (FD) with associated intramuscular myxomas. Data are scarce on the prevalence, clinical features, and natural history of this disorder and outcomes. In this multicenter study, we evaluated a series of patients from 6 European centers. METHODS: All centers affiliated with the European Musculo-Skeletal Oncology Society (EMSOS) were invited to include data on all patients with Mazabraud syndrome who were seen between 1980 and 2015. The study investigated the prevalence of Mazabraud syndrome, the type, severity, and localization of FD lesions in relation to myxomas, the histopathology of myxomas, and results of GNAS-mutation analysis, when available. RESULTS: Thirty-two patients (22 female) from 6 centers were included. The prevalence of Mazabraud syndrome was 2.2% in the combined cohort of 1,446 patients with FD, and the syndrome was diagnosed at a mean of 10.1 years after diagnosis of FD. The myxomas were predominantly localized in the upper leg. Excision was performed in 20 patients, recurrence occurred in 6 of these patients (30%) at a median of 8.5 years (range, 1.9 to 16.0 years), and revision surgery was necessary in 5 (25%). High cellularity of myxomas was associated with recurrence (p < 0.05). A GNAS mutation was identified in the myxoma tissue of 5 (83%) of 6 patients with GNAS-mutation analysis. CONCLUSIONS: This study is the first, to our knowledge, to provide data on the prevalence of Mazabraud syndrome in a relatively large cohort. Although the outcomes of surgical resection were good, a quarter of the patients required revision surgery despite clear resection margins. High cellularity of myxomas was associated with recurrence. GNAS mutations were identified in 83% (5 of 6), emphasizing the shared origin of FD and myxomas. Our data show that patients with FD who have disproportionate complaints, irrespective of FD type, extent, or severity, should be investigated for the possible presence of myxomas. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Denosumab in Patients With Fibrous Dysplasia Previously Treated With Bisphosphonates.

CONTEXT: Fibrous dysplasia/McCune-Albright syndrome (FD/MAS) is a rare bone disorder commonly treated with bisphosphonates, but clinical and biochemical responses may be incomplete. OBJECTIVE: To evaluate the efficacy and tolerability of the receptor activator of nuclear factor-κB ligand inhibitor denosumab in the treatment of patients with FD/MAS refractory to bisphosphonate therapy. DESIGN: Case series. SETTING: Academic center of expertise for rare bone diseases. PATIENTS: Data were collected from 12 consecutive patients with FD/MAS with persistent pain and increased biochemical markers of bone turnover (BTMs) after long-term treatment with bisphosphonates (median, 8.8 years) and were treated with subcutaneous denosumab 60 mg at 3- or 6-month intervals with a follow-up for at least 12 months. MAIN OUTCOME(S): Sustained reduction of BTMs and bone pain. RESULTS: A 60 mg dose of denosumab once every 3 months, but not once every 6 months, induced a sustained reduction of BTMs. After a median treatment period of 15.5 months (range, 12 to 19) serum alkaline phosphatase activity and propeptide of type 1 procollagen levels were respectively reduced from 212 ± 39.4 IU/L to 79 ± 6.0 IU/L (P = 0.004) and from 346.2 ± 111.1 ng/mL to 55.7 ± 16.6 ng/mL (P = 0.023) and normalized in 70% and 75% of patients, respectively. Although not quantitavely measured, 10 patients reported a reduction in bone pain of whom 6 reported complete elimination of pain. Treatment with denosumab was well tolerated. CONCLUSION: Our results indicate that 60 mg of denosumab every 3 months is a promising, well-tolerated treatment of most patients with FD/MAS refractory to bisphosphonate therapy. These results together with those of previously published case reports provide the necessary background for the design of a larger, controlled study.

Improving patient outcomes in fibrous dysplasia/McCune-Albright syndrome: an international multidisciplinary workshop to inform an international partnership.

To develop consensus on improving the management of patients, we convened an international workshop involving patients, clinicians, and researchers. Key findings included the diagnostic delay and variability in subsequent management with agreement to develop an international natural history study. We now invite other stakeholders to join the partnership. PURPOSE: The aim of this study was develop a consensus on how to improve the management of patients with fibrous dysplasia and prioritize areas for research METHODS: An international workshop was held over 3 days involving patients, clinicians, and researchers. Each day had a combination of formal presentations and facilitated discussions that focused on clinical pathways and research. RESULTS: The patient workshop day highlighted the variability of patients' experience in getting a diagnosis, the knowledge of general clinical staff, and understanding long-term outcomes. The research workshop prioritized collaborations that improved understanding of the contemporary natural history of fibrous dysplasia/McCune-Albright syndrome (FD/MAS). The clinical workshop outlined the key issues around diagnostics, assessment of severity, treatment and monitoring of patients. CONCLUSIONS: In spite of advances in understanding the genetic and molecular underpinnings of fibrous dysplasia/McCune-Albright syndrome, clinical management remains a challenge. From the workshop, a consensus was reached to create an international, multi-stakeholder partnership to advance research and clinical care in FD/MAS. We invite other stakeholders to join the partnership.

Clinical presentation of McCune-Albright syndrome in males.

UNLABELLED: The aims of this study were: (a) to survey gender prevalence and clinical findings at diagnosis in a series of patients who manifested at the time of this study the classical triad of McCune-Albright syndrome (MAS); (b) to investigate whether clinical presentation of MAS in boys may be different from that in girls; (c) to confirm whether boys with MAS may show a peculiar picture of testicular microlithiasis (TM) by testicular ultrasonography (US). Twenty-six patients (10 boys) with the classical clinical manifestations of MAS were recruited for the present study from the database of the Italian Multicenter Study Group on MAS. Age at diagnosis of MAS was significantly lower in girls than in boys (p < 0.025). Whilst there was no difference in the prevalence of skin and bone fibrous dysplasia for the two groups, a significantly higher prevalence of peripheral precocious puberty (PPP) was found in girls (chi2 = 6.5, p < 0.025). Moreover, PPP onset was earlier in females than in males (2.8 +/- 2.3 vs. 6.9 +/- 2.7 years, p < 0.005). In one boy, aged 2.9 years, the first clinical manifestation of MAS was monolateral testicular enlargement in the context of a picture of classical PPP. US scanning of the testes, at the time of the present study, showed bilateral hyperechogeneic multiple spots, compatible with diagnosis of TM, in 6/10 boys. CONCLUSIONS: (a) MAS is slightly more frequent in females. (b) PPP in MAS is significantly more frequent and earlier in girls. (c) PPP in boys with MAS is generally associated with bilateral testicular enlargement, but monolateral macroorchidism may also be seen. (d) TM may be another marker for MAS in males.