Clinical course of peripheral precocious puberty in girls due to autonomous ovarian cysts.

OBJECTIVE: Peripheral precocious puberty (PPP) is the precocious development of secondary sexual characteristics without pulsatile gonadotropin-releasing hormone (GnRH) secretion. In girls, PPP suggests a hyper-oestrogenic state, such as autonomous ovarian cysts and McCune-Albright syndrome (MAS). We aimed to investigate PPP in girls with ovarian cysts, with or without MAS. DESIGN: A retrospective study design was used. PATIENTS AND MEASUREMENTS: The study included 12 girls diagnosed with ovarian cysts with PPP between January 2003 and May 2022. Pelvic sonography was performed in cases of vaginal bleeding or areolar pigmentation in PPP. The clinical characteristics, clinical course and pelvic sonographic findings of girls with ovarian cysts were investigated. RESULTS: We found 18 episodes of ovarian cysts in the 12 girls. The median size of the ovarian cysts was 27.5 mm. Five of the girls were diagnosed with MAS. The median time to spontaneous regression was 6 months. Later, 4 out of 12 girls progressed to central precocious puberty (CPP), and three of them had a recurrence of ovarian cysts. Compared to the non-recurrent and recurrent groups, there was a difference in peak luteinizing hormone (LH) in the GnRH stimulation test and period to cyst regression. CONCLUSIONS: Most ovarian cysts in PPP spontaneously disappear. However, this could be one of the findings of MAS. Some girls progress from PPP to CPP. Therefore, follow-up is necessary for ovarian cysts in patients with PPP. The recurrence of ovarian cysts may occur when spontaneous regression is prolonged.

A Mathematical Model for Fibrous Dysplasia: The Role of the Flow of Mutant Cells.

Fibrous dysplasia (FD) is a mosaic non-inheritable genetic disorder of the skeleton in which normal bone is replaced by structurally unsound fibro-osseous tissue. There is no curative treatment for FD, partly because its pathophysiology is not yet fully known. We present a simple mathematical model of the disease incorporating its basic known biology, to gain insight on the dynamics of the involved bone-cell populations, and shed light on its pathophysiology. We develop an analytical study of the model and study its basic properties. The existence and stability of steady states are studied, an analysis of sensitivity on the model parameters is done, and different numerical simulations provide findings in agreement with the analytical results. We discuss the model dynamics match with known facts on the disease, and how some open questions could be addressed using the model.

CT-based radiomics analysis of different machine learning models for differentiating gnathic fibrous dysplasia and ossifying fibroma.

OBJECTIVE: In this study, our aim was to develop and validate the effectiveness of diverse radiomic models for distinguishing between gnathic fibrous dysplasia (FD) and ossifying fibroma (OF) before surgery. MATERIALS AND METHODS: We enrolled 220 patients with confirmed FD or OF. We extracted radiomic features from nonenhanced CT images. Following dimensionality reduction and feature selection, we constructed radiomic models using logistic regression, support vector machine, random forest, light gradient boosting machine, and eXtreme gradient boosting. We then identified the best radiomic model using receiver operating characteristic (ROC) curve analysis. After combining radiomics features with clinical features, we developed a comprehensive model. ROC curve and decision curve analysis (DCA) demonstrated the models' robustness and clinical value. RESULTS: We extracted 1834 radiomic features from CT images, reduced them to eight valuable features, and achieved high predictive efficiency, with area under curves (AUC) exceeding 0.95 for all the models. Ultimately, our combined model, which integrates radiomic and clinical data, displayed superior discriminatory ability (AUC: training cohort 0.970; test cohort 0.967). DCA highlighted its optimal clinical efficacy. CONCLUSION: Our combined model effectively differentiates between FD and OF, offering a noninvasive and efficient approach to clinical decision-making.

Cystic degeneration of the fibrous dysplasia presenting with loss of vision.

Cystic degeneration of the fibrous dysplasia is a very rare clinical condition and may present with loss of vision when it involved the skull base. A 12-year-old female child presented with an enlargement of the skull. She was diagnosed as large skull base and skull vault tumor. She underwent partial removal of the tumor, and custom-made titanium implant was inserted. The diagnosis was fibrous dysplasia. Two years after the initial diagnosis, she presented with total loss of vision at her right eye. Radiological imaging confirmed the cystic degeneration within the tumor. She re-operated and the cyst fluid was evacuated in association with the removal of cyst wall. The diagnosis was the cystic degeneration of the fibrous dysplasia. Her vision was improved a few days after the surgery. Fibrous dysplasia of the skull base should be closely followed-up in order to prevent severe visual complications.

Fibrous dysplasia of the head and neck in Southern Finland: a retrospective study on clinical characteristics, diagnostics, and treatment.

PURPOSE: Fibrous dysplasia (FD) is a rare genetic disease with benign bone tumors. FD can affect one (monostotic FD) or multiple bones (polyostotic FD), with craniofacial lesions being common. Because of its rarity, there are only few clinical reports on FD in the head and neck region and its clinical characteristics remain incompletely defined. This study aimed to determine patient demographics, symptoms, diagnostics, and given treatment in patients with FD of the head and neck in a Finnish population. METHODS: A retrospective review on all patients diagnosed with or treated for FD of the head and neck at the Helsinki University Hospital during 2005-2020. RESULTS: In total 74 patients were identified; 54% were male and the mean age 45 years. Overall 95% had monostotic FD. Mandibula and maxilla were the most common anatomic sites. Majority of patients had symptoms, most commonly pain and lesion growth, and 49% had extra-skeletal symptoms. For all, diagnosis was primarily based on imaging findings, biopsies were obtained from 41%. Altogether 54 patients (73%) were managed by observation only, 20 patients (27%) received treatment; ten bisphosphonates, six surgery and four both. CONCLUSION: Although highly variable in its clinical manifestations, head and neck FD lesions are often symptomatic and impose risk for extra-skeletal complications. Treatment is often conservative but should be individually tailored. Future studies are encouraged to better define the disease characteristics and hopefully offer new treatment possibilities.

Vitamin D Attenuates Fibrotic Properties of Fibrous Dysplasia-Derived Cells for the Transit towards Osteocytic Phenotype.

Fibrous dysplasia (FD) poses a therapeutic challenge due to the dysregulated extracellular matrix (ECM) accumulation within affected bone tissues. In this study, we investigate the therapeutic potential of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in managing FD by examining its effects on FD-derived cells in vitro. Our findings demonstrate that 1,25(OH)2D3 treatment attenuates the pro-fibrotic phenotype of FD-derived cells by suppressing the expression of key pro-fibrotic markers and inhibiting cell proliferation and migration. Moreover, 1,25(OH)2D3 enhances mineralization by attenuating pre-osteoblastic cellular hyperactivity and promoting maturation towards an osteocytic phenotype. These results offer valuable insights into potential treatments for FD, highlighting the role of 1,25(OH)2D3 in modulating the pathological properties of FD-derived cells.

Efficacy of antiresorptive agents in fibrous dysplasia and McCune Albright syndrome, a systematic review and meta-analysis.

Fibrous dysplasia (FD) is a rare skeletal disorder in which normal bone is replaced by a fibro-osseous tissue, resulting in possible deformities and fractures. The aim of this systematic review and meta-analysis was to synthesize the available evidence on the use of antiresorptive drugs in FD in terms of changes in bone turnover markers (BTMs), bone mineral density (BMD), and reducing pain. Three databases were searched in October 2022, with an update in July 2023. Of the 1037 studies identified, 21 were retained after eligibility assessment. A random-effects model was used to calculate global effect size and the corresponding standard error. Pamidronate and Denosumab were the most reported drugs in a total of 374 patients assessed. The initiation of treatments was accompanied by an average reduction of 40.5% [CI95% -51.6, -29.3] in the bone resorption parameters, and 22.0% [CI95% -31.9, -12.1] in the parameters of bone formation after 6-12 months. BMD was increased in both FD lesions and in the unaffected skeleton. Pain was reduced by 32.7% [CI95% -52.7, -12.6] after 6-12 months of treatment, and by 44.5% [CI95% -65.3, -23.6] after a mean 41.2 months of follow-up. The variation in pain was highly correlated to variation in bone resorption (R2 = 0.08, p < 0.0001) and formation parameters (R2 = 0.17, p < 0.0001). This study supports the overall efficacy of antiresorptive therapies in terms of reducing bone remodeling, improving bone density, and pain in FD.

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.

Craniofacial Fibrous Dysplasia: Clinical and Therapeutic Implications.

PURPOSE OF REVIEW: This study aims to review diagnosis, potential complications, and clinical management in craniofacial fibrous dysplasia. RECENT FINDINGS: Fibrous dysplasia (FD) is a rare mosaic disorder in which normal bone and marrow are replaced with expansile fibro-osseous lesions. Disease presents along a broad spectrum and may be associated with extraskeletal features as part of McCune-Albright syndrome (MAS). The craniofacial skeleton is one of the most commonly impacted areas in FD, and its functional and anatomical complexities create unique challenges for diagnosis and management. This review summarizes current approaches to diagnosis and management in FD/MAS, with emphasis on the clinical and therapeutic implications for the craniofacial skeleton.

Benign Brain and Spinal Tumors Originating from Bone or Cartilage.

Benign osseocartilaginous tumors of the spine are overall uncommon, representing between 1 and 13% of all primary bone tumors and less than 10% of all spinal tumors. Tumors in this category include osteoblastic lesions such as the related osteoid osteoma and osteoblastoma, and cartilage-forming lesions including osteochondroma, chondroma, and chondroblastoma. Aneurysmal bone cysts, giant cell tumors of bone, and eosinophilic granulomas also comprise benign tumors of the spine arising from bone. There is significant heterogeneity in the epidemiology, molecular biology, imaging features, and optimal treatment of these lesions. For example, osteoid osteoma is characterized by high expression of the cyclooxygenase enzymes, making it amenable to treatment with anti-inflammatory drugs initially, whereas other lesions such as osteoblastoma may require intralesional curettage or en bloc resection sooner. Generally, en bloc resection is preferred when possible to minimize risk of recurrence. Further, some tumors may arise in the setting of syndromic conditions, such as multiple chondromas arising in Ollier disease or Maffucci syndrome, or as part of genetic disorders, such as osteochondromas in the context of hereditary multiple exostosis. These lesions may present with local pain, cause neurological compromise or be discovered incidentally on routine imaging. The Enneking classification and Weinstein-Boriani-Biagini system are routinely used to classify lesions and assist in surgical planning. More novel techniques such as radiofrequency ablation and laser photocoagulation have been applied for the treatment of osteoid osteoma and may have utility in the treatment of other lesion types. A multidisciplinary approach is critical in the management of benign lesions of the spine, and both chemotherapeutic and surgical approaches are routinely used.

Pharmacological Interventions Targeting Pain in Fibrous Dysplasia/McCune-Albright Syndrome.

Fibrous dysplasia (FD) is a rare, non-inherited bone disease occurring following a somatic gain-of-function R201 missense mutation of the guanine-nucleotide binding protein alpha subunit stimulating activity polypeptide 1 (GNAS) gene. The spectrum of the disease ranges from a single FD lesion to a combination with extraskeletal features; an amalgamation with café-au-lait skin hyperpigmentation, precocious puberty, and other endocrinopathies defines McCune-Albright Syndrome (MAS). Pain in FD/MAS represents one of the most prominent aspects of the disease and one of the most challenging to treat-an outcome driven by (i) the heterogeneous nature of FD/MAS, (ii) the variable presentation of pain phenotypes (i.e., craniofacial vs. musculoskeletal pain), (iii) a lack of studies probing pain mechanisms, and (iv) a lack of rigorously validated analgesic strategies in FD/MAS. At present, a range of pharmacotherapies are prescribed to patients with FD/MAS to mitigate skeletal disease activity, as well as pain. We analyze evidence guiding the current use of bisphosphonates, denosumab, and other therapies in FD/MAS, and also discuss the potential underlying pharmacological mechanisms by which pain relief may be achieved. Furthermore, we highlight the range of presentation of pain in individual cases of FD/MAS to further describe the difficulties associated with employing effective pain treatment in FD/MAS. Potential next steps toward identifying and validating effective pain treatments in FD/MAS are discussed, such as employing randomized control trials and probing new pain pathways in this rare bone disease.

PTHrP Modulates the Proliferation and Osteogenic Differentiation of Craniofacial Fibrous Dysplasia-Derived BMSCs.

Fibrous dysplasia (FD) is a skeletal stem cell disease caused by mutations in the guanine nucleotide-binding protein, alpha-stimulating activity polypeptide (GNAS) gene, which results in the abnormal accumulation of cyclic adenosine monophosphate (cAMP) and hyperactivation of downstream signaling pathways. Parathyroid hormone-related protein (PTHrP) is secreted by the osteoblast lineage and is involved in various physiological and pathological activities of bone. However, the association between the abnormal expression of PTHrP and FD, as well as its underlying mechanism, remains unclear. In this study, we discovered that FD patient-derived bone marrow stromal cells (FD BMSCs) expressed significantly higher levels of PTHrP during osteogenic differentiation and exhibited greater proliferation capacity but impaired osteogenic ability compared to normal control patient-derived BMSCs (NC BMSCs). Continuous exogenous PTHrP exposure on the NC BMSCs promoted the FD phenotype in both in vitro and in vivo experiments. Through the PTHrP/cAMP/PKA axis, PTHrP could partially influence the proliferation and osteogenesis capacity of FD BMSCs via the overactivation of the Wnt/ß-Catenin signaling pathway. Furthermore, PTHrP not only directly modulated cAMP/PKA/CREB transduction but was also demonstrated as a transcriptional target of CREB. This study provides novel insight into the possible pathogenesis involved in the FD phenotype and enhances the understanding of its molecular signaling pathways, offering theoretical evidence for the feasibility of potential therapeutic targets for FD.

A Rare Skeletal Disorder, Fibrous Dysplasia: A Review of Its Pathogenesis and Therapeutic Prospects.

Fibrous dysplasia (FD) is a rare, non-hereditary skeletal disorder characterized by its chronic course of non-neoplastic fibrous tissue buildup in place of healthy bone. A myriad of factors have been associated with its onset and progression. Perturbation of cell-cell signaling networks and response outputs leading to disrupted building blocks, incoherent multi-level organization, and loss of rigid structural motifs in mineralized tissues are factors that have been identified to participate in FD induction. In more recent years, novel insights into the unique biology of FD are transforming our understandings of its pathology, natural discourse of the disease, and treatment prospects. Herein, we built upon existing knowledge with recent findings to review clinical, etiologic, and histological features of FD and discussed known and potential mechanisms underlying FD manifestations. Subsequently, we ended on a note of optimism by highlighting emerging therapeutic approaches aimed at either halting or ameliorating disease progression.

Case Report Of Rib Polyostotic Fibrous Dysplasia.

Polyostotic fibrous dysplasia is a rare benign asymptomatic tumour of the ribs not requiring surgery on most occasions. We present here a case with left 10th and 11th rib fibrous dysplasia which was causing a hinderance to the Urologist for renalstone extraction. Therefore the 10th and 11th ribs were excised followed by chest wall reconstruction.

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.

Muscle function around the hip after operation for Fibrous Dysplasia of Proximal Femur with Varus Deformity.

Objectives: This study aimed to analyse the clinical effect of surgery for patients with fibrous dysplasia (FD) of the proximal femur with varus deformity, detect the muscle function around the hip joint. Methods: This is a retrospective study. A total of 20 patients who underwent operation for FD of the proximal femur with varus deformity at West China Hospital, from January 2018 to October 2022 were included in this study. The peak torque (PT) of muscle strength during abduction, adduction, flexion and extension of bilateral hip joints was measured by an isokinetic muscle test and training system associated with the comparison of bilateral hip joints, to evaluate the function of muscles around the hip joint after operation. Results: The difference between the length of the affected limb and the healthy side was 1~2 cm in seven cases and <1 cm in 13 cases. The force line showed no abnormality in 15 affected limbs, which deviated from the center of the knee joint by 3-5 mm in five cases. The average PT during abduction of hip joints on the affected side of 20 patients was significantly lower than that on the healthy side, which was also reduced evidently during adduction and flexion of hip joints on the affected side compared with that on the healthy side. Conclusions: After effective recovery of the force line and length of the affected limb in patients with FD of the proximal femur with deformity, functional abnormalities of muscles are still present to a certain extent.

Craniofacial Fibrous Dysplasia: Surgical Management and Long-Term Outcomes at a Referral Center in Mexico City.

Background Craniofacial fibrous dysplasia (CFD) is an uncommon benign condition in which a bone is replaced by fibrous tissue. An adequate clinical characterization considering the number of affected bones and functional impairment is important to determine the most effective surgical intervention for its management. This study aims to present our institution's experience in the evaluation and management of CFD. Methods This was a retrospective study that included patients with CFD managed at our institution. Data included demographic characteristics, afflicted bones, surgical procedures performed, and recurrence. Results are presented as mean and percentages. Recurrence-free years and association between the type of surgery and recurrence was evaluated. Results Eighteen patients were included (11 females, 61%). The zygomatic, maxillary, and frontal bones were the most commonly affected with eight (18%) cases each. The most common procedure was bone burring, with 36 procedures. Recurrence was more prevalent after burring (58.3%) and occurred earlier than in the bone resection group (13 vs. 15 years, p > 0.05). Conclusion Surgery continues to be the cornerstone of CFD treatment. Bone burring is effective for debulking and contouring but increases the risk for recurrence. An individualized approach should be tailored according to the anatomical location of the disease, type of CFD, behavior of the lesion, and accompanying clinical complaints.

Lower-limb intramedullary nailing in patients with polyostotic fibrous dysplasia who had a previous unsuccessful treatment. A report of 48 cases.

BACKGROUND: Intramedullary nailing (IN) seems to be the best primary surgical treatment for patients with either polyostotic fibrous dysplasia or McCune-Albright syndrome (PFD/MAS) when the femur and tibia are totally affected by fibrous dysplasia (FD) and pain, fracture and deformity are likely to occur. However, other management protocols have been applied in these cases, often leading to disabling sequelae. This study sought to evaluate if IN could also have been effective as a salvage procedure to provide patients with satisfactory results, regardless of the poor results due to the improper treatment previously performed. MATERIALS AND METHODS: Twenty-four retrospectively registered PFD/MAS patients with 34 femurs and 14 tibias totally affected by fibrous dysplasia had received various treatments with unsatisfactory results in other institutions. Before the IN performed in our hospital, 3 patients were wheelchair bound; 4 were fractured; 17 limped; and many used an aid for walking. Salvage IN was performed in our hospital at a mean patient age of 23.66 ± 6.06 years (range, 15-37 years). The patients were evaluated before-except for the four fractured ones-and after IN using the validated Jung scoring system, and the data were statistically analyzed. RESULTS: The mean length of follow-up after IN was 9.12 ± 3.68 years (range, 4-17 years). The patients' mean Jung score significantly improved from 2.52 ± 1.74 points before IN to 6.78 ± 2.23 at follow-up (p < 0.05). Ambulation was improved in ambulatory patients and restored in wheelchair users. The complication rate was 21%. CONCLUSIONS: Regardless of the high rate of complications, IN may be considered a reliable surgical procedure to salvage a failed treatment in PFD/MAS, with long-lasting satisfactory results achieved in most patients. Trial registration statement: Not applicable. LEVEL OF EVIDENCE: IV.

Extent of Extraskeletal Manifestations of Fibrous Dysplasia/McCune-Albright Syndrome in Patients with Mazabraud's Syndrome.

Mazabraud's syndrome (MZB) is a rare condition in which fibrous dysplasia of bone/the McCune-Albright syndrome (FD/MAS) co-exists with intramuscular myxomas. Both FD and the myxomas harbor the GNAS-mutation. Recent studies have shown that extraskeletal, GNAS-related features are associated with a more severe phenotype of FD/MAS. However, patients with MZB are often only seen by orthopedic surgeons. We therefore evaluated MZB patients seen in tertiary referral centers from the Netherlands (LUMC), USA (National Institutes of Health) and France (INSERM UMR 1033 (Lyos), Hôpital Edouard Herriot). All FD/MAS patients known in these centers with an additional diagnosis of a myxoma were included. Demographic information and data on disease extent and extraskeletal manifestations of FD/MAS such as precocious puberty (PP) or café-au-lait patches (CAL) were retrieved from patient's medical records. Thirty MZB patients were included: 20 women (67%) and 10 men (33%). Patients received a diagnosis of MZB (median 42 years, range 16-19) significantly later than the diagnosis of FD/MAS (median 30 years, range 0-60), p < 0.01. Twenty-six patients were diagnosed with polyostotic disease (87%). In 97% the myxoma was located near the skeletal FD lesion. The combination of MZB and MAS was made in 13 patients in whom PP (n = 7), CAL (n = 7), GH-excess (n = 3) and hyperthyroidism (n = 3) were present. Other extraskeletal features were (multinodular) goiter (n = 2) and thyroid cysts (n = 1). Furthermore, in this cohort of patients with MZB several (pre-)malignant tumors were observed; ductal carcinoma in situ of the breast in 3 patients (10%), breast cancer in 1 patient (3.3%), intra pancreatic mucinous neoplasms in 3 patients (10%) and liver adenomas in 2 patients (6.6%). A total of 47% of patients with MZB had an additional extraskeletal feature such as an endocrinopathy. In MZB, 87% of patients suffer from polyostotic FD, 43% of patients have extraskeletal GNAS-features such as an hyperfunctioning endocrinopathy and 30% (pre-)malignant tumors. We therefore advocate that MZB patients should undergo a complete screening and long-term follow-up for extent of bone disease, but also extraskeletal GNAS features of FD/MAS.

Fibrous dysplasia in cardio-facio-cutaneous syndrome: A case report and review of literature.

Cardio-facio-cutaneous (CFC) syndrome (OMIM #:115150, 615278, 615279, 615280) is a rare genetic condition caused by variants in the RAS/mitogen-activated protein kinase (MAPK) signal transduction pathway. Up to 75% of cases are caused by mutations in the BRAF gene, whereas KRAS gene mutation has only been reported in <2% of cases. CFC syndrome is characterized by cardiac abnormalities, distinctive craniofacial dysmorphism, and various cutaneous abnormalities. Musculoskeletal and orthopedic manifestations are also prevalent in patients with CFC syndrome, among which the most common are skeletal deformities and joint laxities. Dysplastic bone disorders, on the other hand, have not been reported in CFC syndrome before. We report on a case of symmetrical polyostotic fibrous dysplasia (FD) in a patient with CFC syndrome with the KRAS(NM_004985.5):c.57G>C; p.Leu19Phe variant. The FDs were incidentally picked up, and patient was conservatively managed and remained asymptomatic on follow-up. The same variant was reported previously in a patient with Oculoectodermal Syndrome (OES), who developed polyostotic non-ossifying fibroma (NOF). This case explores FD as a possible new clinical feature of CFC syndrome, and when linked to the historical case of OES, explores whether the KRAS(NM_004985.5):c.57G>C; p.Leu19Phe mutation may potentially contribute to the development of dysplastic bone lesions in patients with this particular mutation.