A sensitive mutation-specific screening technique for GNAS1 mutations in cases of fibrous dysplasia: the first report of a codon 227 mutation in bone

Aims: To report on the mutation-specific restriction enzyme digest (MSRED) method using paraffin-embedded tissue as a means of detecting GNAS1 mutations in fibrous dysplasia (FD), and to determine if any of the reported GNAS1 mutations in endocrine neoplasms, not previously documented in FD, can be found in FD. METHODS AND RESULTS: Sixty-seven cases of extragnathic FD were analysed as two groups, 1997-2002 and 2003-06, chosen because tissue fixation and decalcification methods were more accurately recorded in the latter. MSRED revealed that between 2003 and 2006, 93% of 28 'in house' extragnathic cases harboured a GNAS1 mutation, compared with 75% of 32 cases before 2003. Fixation times of no more than 48 h and decalcification in ethylenediamine tetraacetic acid gave the best results. Of the 56 mutations detected (five gnathic, 51 extragnathic), 32 (57%) were R201H, 21 (38%) were R201C and three (5%) were Q227L. Two Q227L extragnathic cases had unusual clinical/radiological findings. No mutations were detected in osteofibrous dysplasia. CONCLUSION: Detection of GNAS1 mutations by MSRED is a valuable adjunct to the histopathological diagnosis of FD. This is the first report of a Q227L mutation in FD, although it has been previously documented in pituitary adenoma.     

The diagnostic utility of the GNAS mutation in patients with fibrous dysplasia: meta-analysis of 168 sporadic cases

GNAS mutations have been implicated in the development of fibrous dysplasia and multiple endocrinopathies of the Albright-McCune syndrome. To investigate the diagnostic utility of GNAS mutations in patients with fibrous dysplasia, we performed mutational analyses of histologically confirmed fibrous dysplasia and conducted a meta-analysis of the literature. We collected 48 cases of fibrous dysplasia from 3 institutions from 2002 to 2011 and performed polymerase chain reaction and direct bidirectional sequencing of exons 8 and 9 of GNAS using paraffin-embedded tissues. We searched MEDLINE, PubMed, and the KoreaMed databases from 1997 to 2011 and included an additional 155 cases of fibrous dysplasia from 8 representative studies to conduct a meta-analysis. In our sample, 28 (58.3%) of 48 cases showed point mutations of codon 201 at exon 8. Twenty-five cases had a substitution of arginine at codon 201 for histidine (p.R201H), and 3 cases had a substitution for cysteine (p.R201C). One case had a new mutation at codon 224 (p.V224A). The incidence of GNAS mutations was significantly greater in cases that involved long bones than in cases that involved flat bones (P = .017) and was higher in polyostotic cases than in monostotic cases (P = .067). In meta-analysis, 9 studies and 203 patients were included. The overall positive rate of GNAS mutation in fibrous dysplasia was 71.9% (146/203). The major types of mutations were missense mutations such as R201H (66.4%) and R201C (30.8%). As a result, the detection of GNAS mutation could be a valuable adjunct to conventional histopathologic diagnosis of fibrous dysplasia.     

Ossifying fibroma of long bone: its distinction from fibrous dysplasia and its association with adamantinoma of long bone.

Two cases of ossifying fibroma of long bones are presented. This tumor is confused with monostotic fibrous dysplasia, but can be distinguished by its intracortical location, as demonstrated radiographically, and by its histologic pattern. Distinction from fibrous dysplasia is important since ossifying fibroma of long bone is a more aggressive lesion with different therapeutic implications. It appears that ossifying fibroma and adamantinoma of long bones are somehow related, and that lesions resembling fibrous dysplasia in association with adamantinomas of long bones are actually ossifying fibromas.     

Juvenile trabecular ossifying fibroma: an update

Fibro-osseous lesions are characterized by the presence of bone marrow that has changed into fibrous tissue and that contains mineralized material of varying appearances. Because of overlapping clinical, radiological, and histopathological features, their classification has evoked much discussion. The current classification recognizes fibrous dysplasia, ossifying fibroma, and osseous dysplasia. Juvenile trabecular ossifying fibroma is a rare variant of ossifying fibroma that is clinically characterized by rapid growth that may suggest malignancy. A series of 15 cases is reported with emphasis on a hitherto unnoticed histological feature that may be helpful in recognizing this lesion.     

Ossifying fibroma.

Our experience includes seven cases of ossifying fibroma. The condition also appears in the literature under diagnostic names such as congenital fibrous dysplasia, congenital osteitis fibrosa, congenital fibrous defect of the tibia, and osteofibrous dysplasia of the tibia and fibula. The lesions develop in childhood and are located in the diaphysis of the tibia, or fibula. Of seven patients, we performed wide excision with free vascularized fibular graft in five cases, wide resection of the distal one-third of the fibula in one case, and curettage and bone graft in one case. Two of the patients who had wide excision with free vascularized fibular graft had recurrence. One case of recurrence occurred where incomplete wide excision with free-vascularized fibular graft was performed because the lesion was too close to the distal epiphysis of the tibia. One of the patients who had curettage and bone graft also had recurrence. It was concluded that children who have an ossifying fibroma requiring surgery can safely be treated with wide excision with or without free-vascularized fibular graft.     

An R201H activating mutation of the GNAS1 (Gsalpha) gene in a corticotroph pituitary adenoma.

In the pituitary gland, activating mutations of the GNAS1 (Gsalpha) gene at Gln227 have been identified in adrenocorticotrophin secreting, growth hormone secreting, and prolactin secreting adenomas. To date, mutations at the codon encoding R201, typically underlying the McCune-Albright syndrome and isolated fibrous dysplasia of bone, have been demonstrated only in growth hormone secreting pituitary adenomas. In this study, a polymerase chain reaction amplified target sequence in exon 8 of the GNAS1 gene was sequenced, identifying the first R201 mutation seen in an isolated basophilic adenoma which generated Cushing's disease in a child. This case adds Cushing's disease to the range of human diseases caused by R201 mutations of the GNAS1 gene.     

Juvenile ossifying fibroma diagnosed on fine needle aspiration cytology: A diagnostic challenge

Preoperative diagnosis of jaw lesions is not always possible on the basis of clinico‐radiological findings alone and needs to be confirmed before attempting any surgical intervention. Fibro‐osseous lesions of the jaw comprise a spectrum of diseases which include cement‐osseous dysplasia, fibrous dysplasia, and ossifying fibroma. The cytomorphological distinction between these individual entities is difficult. We present a case of maxillary fibro‐osseous lesion in an adolescent girl diagnosed and categorized as juvenile ossifying fibroma preoperatively on cytology and confirmed on histopathology. Although aspirates are usually paucicellular in fibro‐osseous lesions, certain cytological features if present in cellular cytosmears can offer further categorization and a definitive diagnosis may be possible in light of clinico‐radiological correlation. Diagn. Cytopathol. 2015;43:75–79. © 2014 Wiley Periodicals, Inc.     

Fine needle aspiration cytology in a case of fibrous dysplasia of jaw

Fibro‐osseous lesions of the jaw comprise of a spectrum of diseases which include osseous dysplasia, fibrous dysplasia, and ossifying fibroma. The differentiation amongst these individual pathological lesions is difficult and a combined clinico‐radiological and histological correlation is essential for exact categorization. Fine needle aspiration cytology (FNAC) is frequently carried out to distinguish between benign and malignant lesions of the jaw as is a quick and reliable modality of investigation which guides in further management. We report, a case of a jaw swelling in a young male, diagnosed as fibrous dysplasia on FNAC. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

A comparative study of fibrous dysplasia and osteofibrous dysplasia with regard to expressions of c-fos and c-jun products and bone matrix proteins: a clinicopathologic review and immunohistochemical study of c-fos, c-jun, type I collagen, osteonectin, osteopontin, and osteocalcin

Fibrous dysplasia and osteofibrous dysplasia are both benign fibro-osseous lesions of the bone and are generally seen during childhood or adolescence. Histologically, the features of these bone lesions sometimes look quite similar, but their precise nature remains controversial. We retrospectively studied clinicopathologic findings in 62 cases of fibrous dysplasia and 20 cases of osteofibrous dysplasia with regard to their anatomic location and histological appearance. From among these cases, the immunohistochemical expressions of c-fos and c-jun proto-oncogene products and bone matrix proteins of type I collagen, osteonectin, osteopontin, and osteocalcin were evaluated in 20 typical fibrous dysplasias and 17 osteofibrous dysplasias using paraffin sections, and these expressions were then assessed semiquantitatively. Microscopically, fibrous dysplasia showed various secondary changes, such as hyalinization, hemorrhage, xanthomatous reaction, and cystic change in 22 of the 62 cases (35%). This was a higher incidence than in osteofibrous dysplasia, in which only 2 of the 20 cases (10%) showed such changes. In the elderly fibrous dysplasia cases, the cellularity of fibroblast-like cells was rather low, and those cases were hyalinized. Almost all of the cases of fibrous dysplasia and osteofibrous dysplasia showed positive expressions of c-fos and c-jun products. The expressions of type I collagen and osteopontin showed no difference between fibrous dysplasia and osteofibrous dysplasia. Immunoreactivity for osteonectin in bone matrix was detected in only 1 case of fibrous dysplasia (1 of 20), whereas it was recognized in 14 of the 17 cases of osteofibrous dysplasia. Furthermore, the immunoreactivity for osteocalcin in bone matrix and fibroblast-like cells was higher in fibrous dysplasia than it was in osteofibrous dysplasia, semiquantitatively. Our immunohistochemical results regarding osteonectin and osteocalcin suggest that the bone matrix of fibrous dysplasia is somewhat more mature than that of osteofibrous dysplasia, and that the fibroblast-like cells in fibrous dysplasia share some phenotypic features with osteoprogenitor cells of normal osteogenic tissues. Fibrous dysplasia and osteofibrous dysplasia share some similar histological features, including c-fos and c-jun expressions, although different clinicohistologic features and immunohistochemical expressions of osteonectin and osteocalcin were observed. These features suggest that the mechanisms behind the development of fibrous dysplasia and osteofibrous dysplasia are similar, but this is not necessarily indicative of a closer relationship between the 2 diseases.     

A comparative study of fibrous dysplasia and osteofibrous dysplasia with regard to expressions of c-fos and c-jun products and bone matrix proteins: A clinicopathologic review and immunohistochemical study of c-fos, c-jun, type I collagen, osteonectin, osteopontin, and osteocalcin

Fibrous dysplasia and osteofibrous dysplasia are both benign fibro-osseous lesions of the bone and are generally seen during childhood or adolescence. Histologically, the features of these bone lesions sometimes look quite similar, but their precise nature remains controversial. We retrospectively studied clinicopathologic findings in 62 cases of fibrous dysplasia and 20 cases of osteofibrous dysplasia with regard to their anatomic location and histological appearance. From among these cases, the immunohistochemical expressions of c-fos and c-jun proto-oncogene products and bone matrix proteins of type I collagen, osteonectin, osteopontin, and osteocalcin were evaluated in 20 typical fibrous dysplasias and 17 osteofibrous dysplasias using paraffin sections, and these expressions were then assessed semiqnantitatively. Microscopically, fibrous dysplasia showed various secondary changes, such as hyalinization, hemorrhage, xanthomatous reaction, and cystic change in 22 of the 62 cases (35%). This was a higher incidence than in osteofibrous dysplasia, in which only 2 of the 20 cases (10%) showed such changes. In the elderly fibrous dysplasia cases, the cellularity of fibroblast-like cells was rather low, and those cases were hyalinized. Almost all of the cases of fibrous dysplasia and osteofibrous dysplasia showed positive expressions of c-fos and c-jun products. The expressions of type I collagen and osteopontin showed no difference between fibrous dysplasia and osteofibrous dysplasia. Immunoreactivity for osteonectin in bone matrix was detected in only 1 case of fibrous dysplasia (1 of 20), whereas it was recognized in 14 of the 17 cases of osteofibrous dysplasia. Furthermore, the immunoreactivity for osteocalcin in bone matrix and fibroblast-like cells was higher in fibrous dysplasia than it was in osteofibrous dysplasia, semiquantitatively. Our immunohistochemical results regarding osteonectin and osteocalcin suggest that the bone matrix of fibrous dysplasia is somewhat more mature than that of osteofibrous dysplasia, and that the fibroblast-like cells in fibrous dysplasia share some phenotypic features with osteoprogenitor ceils of normal osteogenic tissues. Fibrous dysplasia and osteofibrous dysplasia share Some similar histological features, including c-fos and c-jun expressions, although different clinicohistologic features and immunohistochemical expressions of osteonectin and osteocalcin were observed. These features suggest that the mechanisms behind the development of fibrous dysplasia and osteofibrous dysplasia are similar, but this is not necessarily indicative of a closer relationship between the 2 diseases.     

c-myc、p53和p16的表达及GNAS1基因突变在骨的纤维结构不良中的意义

目的 检测c-myc、p53和p16蛋白在骨的纤维结构不良(FD)中的表达及其意义,检测FD中GNAS1基因第8外显子突变,探讨FD的病变性质.方法 采用免疫组织化学SP法检测35例FD(包括1例FD恶变,1例Mazabraud综合征)及20例对照组(10例骨痂、10例骨肉瘤)中c-myc、p53和p16蛋白表达.采用基因组DNA抽提、PCR扩增及基因测序的方法检测35例FD中GNAS1基因第8外显子突变情况.结果 91%(32/35)FD中检测到c-myc蛋白表达,与阴性对照组相比差异具有统计学意义(P=0.001).p53阳性表达仅出现于1例FD合并骨肉瘤变病例中.p16蛋白在34例FD中阳性,与阳性对照组相比差异具有统计学意义(P=0.001).35例FD中,12例GNAS1基因第8外显子DNA扩增成功,其中2例(1例Mazabraud综合征的FD;1例单骨性FD)检测到GNAS1基因突变.结论 c-myc可能是除c-fos外的又一FD相关的原癌基因,p16基因的异常表达在FD的形成过程中可能起重要作用,p53蛋白过表达有助于FD恶变的预测及预后的判断.FD中存在有GNAS1的基因突变.FD是多种因素共同作用导致的骨成熟障碍的肿瘤性病变.     

Confocal Laser Scanning Microscopy Analysis of 10 Cases of Craniofacial Fibrous Dysplasia

Fibro-osseous lesions (FOL) represent a heterogeneous group of lesions that exhibit a variety of clinic-pathological features. Recently, based on the new World Health Organization classification system, these lesions were reclassified as follows: (1) fibrous dysplasia (FD), (2) osseous dysplasia, and (3) ossifying fibroma. Nevertheless, the nosologic placement of FOL may be problematic because of substantial overlap in the histopathological findings. In this study, we analyzed 10 cases of FD by both optical and confocal laser scanning microscopy, a research technique based on the laser light microscopic analysis of stained biological samples that allows improved tissue imaging and bidimensional pictures with high resolution at the cellular level to provide a better understanding of the diagnosis of this disease.     

Clinicopathological study of non-neoplastic lesions of nasal cavity and paranasal sinuses

An analysis of cases presenting as mass in nasal cavity (NC), paranasal sinuses (PNS), and nasopharynx (NP) was done over a period of 7 years in Jawaharlal Nehru Medical College, Aligarh. A provisional diagnosis was made after clinical assessment and radiological investigations, but final diagnosis was made after histopathological examination. The incidence of masses in NC, PNS, and NP was 34.3 cases per year, non-neoplastic lesions constituted 60% of these cases and their incidence was 20.7 cases per year. All the cases were carefully examined histopathologically and it was found that the region was affected by a variety of non-neoplastic lesions. Among 240 cases, 145 were non-neoplastic and 95 were neoplastic The lesions in the decreasing order of frequency were - nasal polyp, rhinoscleroma, tuberculosis, fungal infection, fibrous dysplasia, ossifying fibroma, cysts, nasal glioma, and cemento-ossifying fibroma. NP was involved by a range of neoplastic lesions; however, no non-neoplastic lesion was seen in this region.     

Melatonin deficiency and fibrous dysplasia: might a relation exist?

Fibrous dysplasia of bone might be monostotic, polystotic, or occurs as a part of McCune-Albright syndrome and Jaffe-Lichtenstein syndrome. Activating mutations of GNAS1 gene was identified in patients with fibrous dysplasia. However, fibrous dysplasia might occur in the absence of these mutations and fibrous dysplastic tissue was produced in vitro by the effects of excess exogenous cAMP on human osteogenic cells. It was proved that the fibrous dysplastic tissue is deficient in bone sialoprotein. Melatonin deficiency might be hypothesized in syndromes associated with fibrous dysplasia or formation of fibrous dysplasia-like tissue. The receptor RZR/ROR is the nuclear receptor of melatonin and the human bone sialoprotein gene contains a RZR/ROR response element. It was supposed that binding of melatonin to its membrane receptors results in changes in the levels of activity of nuclear cAMP that lead to alteration of expression of bone sialoprotein. Also, melatonin deficiency might increase cAMP in bone through its effect on prostaglandins of the E group. Further, melatonin deficiency might explain precocious puberty in cases of McCune-Albright syndrome. We might hypothesize that melatonin deficiency might play a role in development of fibrous dysplasia in some cases.     

Activating Gsα mutation in intramuscular myxomas with and without fibrous dysplasia of bone

Activating missense mutations in the Arg 201 codon of the gene encoding the α subunit of Gs, the G protein that stimulates cAMP formation, have been recognized as the cause of many endocrine diseases, McCune-Albright syndrome and isolated fibrous dysplasia of bone. On the other hand, intramuscular myxomas with fibrous dysplasia, so-called Mazabraud’s syndrome, have been sporadically reported, but it has not been confirmed whether intramuscular myxoma, with or without fibrous dysplasia, is associated with the Gsα mutations. We investigated the presence of the Gsα mutations in intramuscular myxomas with or without fibrous dysplasia by a PCR-SSCP assay, using formalin-fixed, paraffin-embedded tissues. In five of the six intramuscular myxomas (three with and two without fibrous dysplasia), point mutations were detected as aberrant bands by SSCP, which were confirmed by a subsequent sequence analysis (three Arg to His and two Arg to Cys). This result suggests that the Gsα mutations are related to tumorigenesis in intramuscular myxoma and that intramuscular myxoma is one of the diseases induced by abnormal Gsα protein. Received: 10 December 1999 / Accepted: 22 February 2000     

Giant cell reparative granuloma: a comparative clinicopathologic study of lesions in gnathic and extragnathic sites

This study attempts to define the clinicopathologic aspects of extragnathic giant cell reparative granuloma (GCRG) by contrasting it with the much better recognized GCRG of jaw bones and highlights the manifestations that are unique to the extragnathic localization. Ninety-one GCRGs of 89 patients, 22 in jaw bones and 69 in the extragnathic bones, were examined. Females were affected twice as frequently as males in both groups. The age distribution of extragnathic GCRGs overlaps that of gnathic counterparts. Small bones of the hands (17 lesions) and feet (16 lesions) were the most common sites for extragnathic lesions. The radiographic findings were nonspecific. Histology of extragnathic lesions was closely similar to that of lesions affecting the jaw. These giant cell lesions should be distinguished from giant cell tumors. Int J Surg Pathol 9(3):189-200, 2001     

Benign fibro-osseous lesions of the jaws: a study of 127 Chinese patients and review of the literature

The aim of this study is to analyze all the cases of benign fibro-osseous lesions treated at School and Hospital of Stomatology, Wuhan University, to compare the results obtained in this study with those previously documented by other authors. The 127 cases diagnosed as a fibro-osseous lesion were retrieved, and information about these lesions was documented. In all, 127 cases of benign fibro-osseous lesions were surgically treated. Of these, 55 were cemento-ossifying fibroma, 43 ossifying fibroma, and 29 fibrous dysplasia. Cemento-ossifying fibromas mostly occur in men of the second decades, mostly in the mandible. Ossifying fibromas had almost equal sex predilection and age distribution peaked in the second decades, mostly in the mandible. Fibrous dysplasia also had equal sex predilection, and age distribution peaked in the second and third decades, with equal occurrence in both jaws. The tumors needed to have a regular follow-up after the surgery.     

Juxta-articular myxoma and intramuscular myxoma are two distinct entities

Juxta-articular myxoma is a rare myxoid tumor of soft tissue that bears a close histologic resemblance to intramuscular myxoma but is distinguished from the latter by its clinical setting and behavior. Activating missense mutations at the Arg 201 codon of the Gs alpha gene ultimately leading to increased levels of cyclic adenosine monophosphate have been implicated in McCune-Albright syndrome and sporadic fibrous dysplasia of bone. Recently, we have demonstrated that the same Gs alpha mutations occur in intramuscular myxomas associated with fibrous dysplasia of bone (Mazabraud's syndrome) as well as in sporadic intramuscular myxoma. The overlapping histologic appearances of juxta-articular myxoma and intramuscular myxoma prompted us to investigate whether there is a relationship between the two entities. We studied this possibility by looking for Gs alpha mutations in juxta-articular myxoma using polymerase chain reaction (PCR) to amplify appropriate genomic DNA fragments extracted from formalin-fixed, paraffin-embedded specimens of five juxta-articular myxomas, followed by single-strand conformation polymorphism analysis. Using these techniques, no aberrant bands were detected in any of the five juxta-articular myxomas, indicating that they lack Gs alpha mutations. Moreover, DNA sequencing of the PCR products of two JAMs showed no abnormalities. We conclude that juxta-articular myxomas, in contrast to intramuscular myxomas, do not involve Arg 201 mutations of the Gs alpha gene, indicating that they represent distinct entities with different underlying molecular mechanisms.     

非颌骨骨化性纤维瘤(附10例病理活检及X线资料)

非颔骨的骨化性纤维瘤极为少见。我们教研室自1975年至1982年七年间的59395例活检例中仅见10例。关于本组肿瘤的病理学及X线的特点,国外报道不多,国内仅见个别专题报道,现将我们的10例报道如下。材料和方法10例患者均为我校附属一院骨科住院     

Activating Gs alpha mutation at the Arg201 codon in liposclerosing myxofibrous tumor

Liposclerosing myxofibrous tumor (LSMFT) is a benign fibro-osseous lesion that is characterized by mixture of histologic elements including lipoma, fibroxanthoma, myxoma, ischemic ossification, and fibrous dysplasia (FD)-like features. These tissue components are seen in the original reports of FD; however, the relationship between LSMFT and FD is not clear. Point mutation of the alpha subunit of G protein (Gs alpha), which increases cyclic adenosine monophosphate formation, has been recognized as the cause of McCune-Albright syndrome as well as polyostotic and monostotic FD of bone. Gs alpha mutation at the Arg201 codon in 2 patients of LSMFT was demonstrated in the present study. Although direct sequencing analysis using the fresh-frozen materials could not detect the mutation, the polymerase chain reaction fragmentation length polymorphism (PCR-RFLP) disclosed the missense point mutation Gs alpha at the Arg201 codon in 2 cases involving LSMFT. This result strongly suggests that a subset of LSMFT is a variant form of FD.