[Fibrous craniofacial dysplasia]

A case report of fibrous dysplasia affecting only the craniofacial right side, in a 56-year-old woman, seen in our outpatients Department suffering from fronto-orbital headache and subjective hypoacusis of the right side, besides a syndrome of dizziness of 6 years development.

Cranio-facial fibrous dysplasia in a 38-year-old African woman: a case history

A 38-year-old woman sought treatment with cranio-facial dysplasia involving the cranium, maxilla and the mandible. Her chief complaint was a mandibular swelling, which had appeared about 2 years previously, had gradually enlarged, and was associated with spontaneous pain. X-ray film examination revealed a ground-glass opacity with blurred demarcation and a 99 Tc medronate bone scan disclosed an increase in tracer uptake in the cranium, maxilla and mandible. The rest of the skeleton was not affected. Histological examination of the lesions revealed solid proliferation of spindle-shaped cells associated with islands of osteid and bone trabecullae with Chinese letter pattern and numerous multinucleated giant cells consistent with fibrous dysplasia. The continued osteoblastic activity of involved bones, coupled with the medical condition of the patient, restricted the management of the patient to largely supportive and palliative care.

A simple bone cyst containing secretory cells in its lining membrane in a patient with polyostotic fibrous dysplasia

An 11-year-old boy, severely affected with polyostotic fibrous dysplasia, showed radiographically rapid expansion of a cystic lesion in his right humerus. At biopsy, there was an extraordinarily thin shell of bone and a cavity encapsulated by a hypertrophic fibrous membrane and filled with yellow serous fluid. Histologically, in addition to typical features of fibrous dysplasia, the fibrous capsule membrane was composed of proliferated mesenchymal cells characteristic of the affected bone. Ultrastructurally, many secretory granules were observed in numerous cytoplasmic vacuoles in the capsular cells as well as in the cultured cells isolated from the evacuated fluid.

Illustrative disorders of ectopic skeletal morphogenesis: a childhood parallax for studies in gravitational and space biology

Heterotopic ossification is a key feature of at least three distinct genetic disorders of osteogenesis in humans: fibrodysplasia ossificans progressiva, progressive osseous heteroplasia, and Albright's hereditary osteodystrophy. All three conditions are genetic disorders of childhood, but the pathobiology of osteogenic induction, the histopathology of osteogenesis, the anatomic distribution of heterotopic lesions, and the developmental patterns of disease progression differ among the three conditions. The phenotypic distinction of these disorders is critically important in counselling patients and families as well as in advancing research to define the molecular pathophysiology of heterotopic osteogenesis in these disabling genetic disorders. Genetic disorders of tissue modeling and morphogenesis provide an important parallax to disturbances of tissue re-modeling that are of paramount importance to gravitational and space biologists as humans begin to explore and live in environments beyond the planet on which they evolved. Disorders of osteogenesis are of particular concern to space biologists due to the dramatic changes in skeletal biology in altered gravitational fields.

A case of pituitary adenoma associated with McCune-Albright syndrome

A 11-year-old boy presented with right temporal hemianopsia and was evaluated of a possible pituitary adenoma. At the age of six, he underwent surgery for facial deformities due to fibrous dysplasia. On admission, he had acromegalic features, was 170 cm tall, weighing 66 kg. The left side of his face was slightly deformed, and a café-au-lait spot was found on his right face. Endocrinologic examination revealed elevated basal level of serum GH (103.6 ng/ml, normal < 3 ng/ml) and PRL (259.1 ng/ml, normal < 30 ng/ml). Other endocrine functions were normal. CT showed hyperostosis of the right frontal, occipital, sphenoidal and maxillary bones. Magnetic resonance imaging (MRI) revealed a pituitary macroadenoma with intraadenomatous cyst. On the basis of physical, endocrinologic and neuroradiologic examination, our diagnosis was pituitary adenoma with McCune-Albright syndrome. Surgery was performed by subfrontal approach. By light microscopy, the pituitary tumor represented a typical acidophilic adenoma. Immunoreactivity for GH and PRL were evident in most of the adenoma cells. Double immunostaining for GH and PRL demonstrated the co-existence of the two hormones in a few adenoma cells. However the majority of cells expressed only one hormone. After surgery the right temporal hemianopsia improved. Postsurgical endocrinologic examination revealed reduction in basal serum GH and PRL levels. Administration of bromocriptine decreased blood PRL levels but it had a limited action on GH hypersecretion.

The histopathology of fibrous dysplasia of bone in patients with activating mutations of the Gs alpha gene: site-specific patterns and recurrent histological hallmarks

Gs alpha mutations and histopathology have been analysed in a series of 13 patients with fibrous dysplasia (FD) of bone, including 12 patients with the McCune-Albright syndrome (MAS) and one patient with monostotic FD. Activating mutations (either R201C or R201H) of the gene encoding the alpha subunit of the stimulatory G protein, Gs, were detected in all cases, including the case of monostotic FD, using a variety of techniques [reverse transcription-polymerase chain reaction (RT-PCR) with allele-specific primers, allele-specific oligonucleotide hybridization, and DNA sequencing]. A spectrum of bone lesions associated with such mutations was identified and it was possible to recognize three primary, but distinct, histological patterns, defined here as Chinese writing type, sclerotic/Pagetoid type, and sclerotic/hypercellular type, which are characteristically associated with the axial/appendicular skeleton, cranial bones, or gnathic bones, respectively. Features of FD histopathology were characterized by confocal fluorescence microscopy, which allowed the definition of osteogenic cell shape changes and 'Sharpey fibre bone' as common denominators of all histological subtypes. Defining characteristics of the different subtypes, two of which diverge from standard descriptions of FD and have never been characterized before, were dependent on the amount and structure of bone tissue within the FD lesion. These data emphasize the non-random (site-specific) variability of FD histopathology in patients carrying activating mutations of the Gs alpha gene and provide additional evidence for the occurrence of Gs alpha mutations in cases of FD other than typical MAS.

Polyostotic fibrous dysplasia associated with intramuscular myxomas: Mazabraud's syndrome

Mazabraud's syndrome, though uncommon, is reported increasingly frequently. It represents an entity readily recognisable radiologically on MR imaging. Awareness of the syndrome, particularly when the myxoma is solitary, can prevent misdiagnosis of intramuscular myxomas (especially when large) as malignant mesenchymal tumors containing myxoid tissue. We review the 34 cases previously reported in the literature and include a recent case from our center.

Reproduction of human fibrous dysplasia of bone in immunocompromised mice by transplanted mosaics of normal and Gsalpha-mutated skeletal progenitor cells

We have isolated progenitor cells from the stromal system of the fibrous dysplastic marrow of patients with McCune-Albright Syndrome. Analysis of the Gsalpha gene from individual colonies provided direct evidence for the presence of two different genotypes within single fibrous dysplastic lesions: marrow stromal cells containing two normal Gsalpha alleles, and those containing one normal allele and an allele with an activating mutation. Transplantation of clonal populations of normal cells into the subcutis of immunocompromised mice resulted in normal ossicle formation. In contrast, transplantation of clonal populations of mutant cells always led to the loss of transplanted cells from the transplantation site and no ossicle formation. However, transplantation of a mixture of normal and mutant cells reproduced an abnormal ectopic ossicle recapitulating human fibrous dysplasia and providing an in vivo cellular model of this disease. These results provide experimental evidence for the necessity of both normal and mutant cells in the development of McCune-Albright Syndrome fibrous dysplastic lesions in bone.

McCune-Albright syndrome progressing with severe fibrous dysplasia

We present the case of an 11-year-old girl with McCune-Albright syndrome associated with severe fibrous dysplasia. In addition to bone lesions, she has apparent manifestations of precocious puberty. In examination, a mass at the mentum spreading to mandibular corpus bilaterally was seen. This mass has affected the mandibular teeth. It was nearly 20 x 20 x 15 cm in size and had local necrotic regions on it. The lower lip was expanded too much by the mass. Another mass filled the left maxillary sinus, expanding the left zygomatic region outwardly and closing the left nasal fossa completely. A rectangular skull shape was related to the involvement of cranial bones. After stainless steel, custom-made mandibular prosthesis was prepared, the patient underwent surgery. A partial mandibulectomy was performed, and resulting mandibular bone defect was reconstructed by steel prosthesis. Craniofacial involvement occurs in 100% of disseminated cases. In the dental literature, mandibular involvement was found in 20% of cases. However, in studied literature, we did not find a dramatic mandibular lesion as severe as that presented here.

Fibrous dysplasia of bone in the McCune-Albright syndrome: abnormalities in bone formation

In addition to café-au-lait pigmentation patterns and hyperendocrinopathies, fibrous dysplasia of bone is a major finding in the McCune-Albright syndrome. Activating missense mutations of the Gs alpha gene leading to overactivity of adenylyl cyclase have been identified in patients with McCune-Albright syndrome, but the mechanism leading to the specific development of fibrous dysplasia in bone has not been elucidated. By means of specific peptide antisera and reverse transcriptase polymerase chain reaction in situ hybridization, we show that expression of Gs alpha and its mRNA is critically up-regulated during maturation of precursor osteogenic cells to normal osteoblast cells and that this pattern of expression is retained in fibrous dysplasia. A functional characterization of fibrous dysplastic tissues revealed that the fibrotic areas consist, in fact, of an excess of cells with phenotypic features of pre-osteogenic cells, whereas the lesional bone formed de novo within fibrotic areas represents the biosynthetic output of mature but abnormal osteoblasts. These cells are noted for peculiar changes in cell shape and interaction with matrix, which were mimicked in vitro by the effects of excess exogenous cAMP on human osteogenic cells. Osteoblasts involved with the de novo deposition of lesional bone in fibrous dysplasia produce a bone matrix enriched in certain anti-adhesion molecules (versican and osteonectin), and poor in the pro-adhesive molecules osteopontin and bone sialoprotein, which is in contrast to the high levels of these two proteins found in normal de novo bone. Our data indicate the need to reinterpret fibrous dysplasia of bone as a disease of cells in the osteogenic lineage, related to the effects of excess cAMP on bone cell function. They further suggest that a critical, physiological, maturation-related regulation of Gs alpha levels makes cells in the osteogenic lineage a natural target for the effects of mutations in the Gs alpha gene and may provide a clue as to why bone itself is affected in this somatic, mutation-dependent disease.

[A case of facial fibrous dysplasia in brothers]

Fibrous dysplasia is a benign bone tumor. The cranio-facial localization concern 20% of fibrous dysplasia. A congenital etiology is evoked by all the authors. Our observations ask for the real etiology of this affection: Congenital? Familial? The diagnosis is done by anatomo-pathology, and surgery is the treatment for severe cases. Relapses are frequent.

[Oral pathology in children. Part III. Abnormalities of the jaw bones]

Diseases of the jaw bones in children can be monostotic or polyostotic. Examples are fibrous dysplasia and Langerhans cell granulomatosis. Sarcomas of the jaw bones are rare, but do occur with some preference in children. The dentist should be aware of the clinical and even more so of the rather typical radiologic changes in such diseases.

Increased proliferation of osteoblastic cells expressing the activating Gs alpha mutation in monostotic and polyostotic fibrous dysplasia

We studied the osteoblastic abnormalities resulting from activating mutation of the Gs alpha gene in two patients with McCune-Albright syndrome and one patient with monostotic fibrous dysplasia. Histomorphometric analysis of dysplastic lesions showed a low number of differentiated osteoblasts along the bone surface and numerous immature alkaline phosphatase-positive mesenchymal cells actively depositing a woven bone matrix. Osteoblastic cells isolated from dysplastic bone lesions expressed a missense mutation in the Gs alpha gene in position 201 and showed increased intracellular basal cyclic adenosine 3',5'-monophosphate levels compared with normal cells isolated from a noninvolved area in the same patient. Cell proliferation evaluated by DNA synthesis was two-fold to threefold greater in osteoblastic cells expressing the mutation compared with normal cells from the same patient and was greater in cells isolated from more severe than less severe fibrotic lesions. In contrast, the synthesis of osteocalcin, a marker of mature osteoblasts, was lower in osteoblastic cells expressing the Gs alpha mutation compared with normal cells from the same patient and was lower in cells isolated from severe compared with less severe fibrotic lesions, indicating that the increased growth in mutated osteoblastic cells was associated with reduced cell differentiation. The results show that activating mutation of Gs alpha in osteoblastic cells leads to constitutive activation of adenylate cyclase, increased cell proliferation, and inappropriate cell differentiation, resulting in overproduction of a disorganized fibrotic bone matrix in polyostotic and monostotic fibrous dysplasia.

Fibrous dysplasia of bone: case report with autopsy study 80 years after the original clinical recognition of the bone lesions

We present a report of the histological features of the bone lesions in a case of polyostotic fibrous dysplasia studied at autopsy in a patient aged 88 years. While much of the fibrous tissue of the lesions contained the trabeculae of non-lamellar bone that are a feature of fibrous dysplasia in young patients, other parts of the lesions showed evidence of osteoclastic remodelling of bone trabeculae, and even of the replacement of some of these structures by mature lamellar bone.

Maxillary malignant mesenchymoma and massive fibrous dysplasia

This is the first report (to our knowledge) that describes a patient with massive polyostotic fibrous dysplasia involving the calvaria and facial skeleton that subsequently underwent transformation to a malignant mesenchymoma with elements of chondrosarcoma, osteosarcoma, and rhabdomyosarcoma arising in the maxilla. Malignant transformation occurred in the absence of prior radiation exposure, osteomyelitis, or known bony infarction. A review of the literature did not reveal any similar cases of massive fibrous dysplasia of the maxilla degenerating to multiple simultaneous malignant histotypes.

Bilateral osteofibrous dysplasia: a report of two cases and review of the literature

Images

Spontaneous malignant transformation of fibrous dysplasia

OBJECTIVE

To evaluate the clinical and radiological findings in diagnosing spontaneous malignant transformation of fibrous dysplasia.

METHODS

Fifteen cases of sarcomatous transformation proved by operation and pathological examinations were found in a group of 356 patients with fibrous dysplasia, and their radiological manifestations were retrospectively studied. The 15 cases included 8 osteosarcomas, 5 fibrosarcomas and 2 chondrosarcomas. All the 15 patients were known to have long-standing fibrous dysplasia, but no radiation therapy was ever received. Eleven patients had polyostotic fibrous dysplasia and 4 had monostotic type.

RESULTS

Malignant transformation most frequently occurs in the cystic expansive lesion of the long tubular bone. Pains, swelling and late appearance of a bony mass are the main clinical manifestations. The early radiological features of sarcomatous transformation in fibrous dysplasia are moth-eaten or cystic areas of osteolysis located in the involved bone. The cortical destruction and gradual formation of a soft tissue mass that contains tumor-bone are highly suspicious of osteosarcomatous transformation, while ring-like and spotty calcification in the tumor matrix is indicative of chondrosarcoma. Fibrosarcoma usually shows simple osteolytic destruction.

CONCLUSIONS

According to the clinical radiological findings, patients of sarcomatous transformation can be detected in the early stage. These radiological findings may be used as a clue for differentiating various kinds of sarcomatous transformation.

Fibrous dysplasia of the spine, costae and hemipelvis with sarcomatous transformation

We describe a patient with polyostotic fibrous dysplasia and secondary malignant fibrous histiocytoma in a spinal lesion.

Fibro-osseous lesions of the head and neck

In recent years the term "fibro-osseous lesions" has gained wide acceptance as a general designation for certain pathological processes of the craniofacial bones. These lesions comprise a challenging group of pathologic conditions that cause difficulty in classification and treatment. Common to all of these pathologic entities is the replacement of normal bone architecture by a benign fibrous tissue composed of fibroblasts and collagen and which contains varying amounts of mineralized material. Categorization of the fibro-osseous lesions is dependent upon correlation of the patient's history, clinical findings, radiographic criteria, and histopathologic determination. This article discusses two of the most commonly confused benign fibro-osseous lesions: fibrous dysplasia and ossifying fibroma.

[Primary cutaneous osteoma in hereditary Albright osteodystrophy]

Cutaneous osteomas occur rarely; they represent the formation of bone in the skin. Primary and secondary forms of ossification can be distinguished. We describe the primary form of ossification in a child with Albright's hereditary osteodystrophy.

Polyostotic fibrous dysplasia. A long-term follow up of 8 patients

Eight patients who had polyostotic fibrous dysplasia were followed up for more than 10 years. One had the Albright syndrome. Two of 3 proximal femoral lesions which were treated before puberty by either curettage and bone grafting or by osteotomy, developed progressive deformity during the growth period. One of 2 proximal femoral lesions treated by curettage and bone grafting after the age of 18 also developed a deformity. Two tibial lesions operated on at the age of one and 30 years remained stable. The histological findings showed more active lesions in young patients compared with adults.

Familial Albright's hereditary osteodystrophy with hypoparathyroidism: normal structural Gs alpha gene

Albright's hereditary osteodystrophy (AHO) is a characteristic skeletal phenotype, including short stature, obesity, round face, and brachydactyly. AHO appears in patients with pseudohypoparathyroidism (PHP) who have resistance to PTH and in their eumetabolic family members who have pseudopseudohypoparathyroidism (PPHP). The differential diagnosis of AHO in families without PHP includes brachydactyly E, whose existence as a distinct entity has been questioned. We studied a patient with familial AHO who presented with hypocalcemia. To our surprise, PTH levels were low, and the response to PTH administration was normal. This is the first case of familial AHO with hypoparathyroidism. The proband's family included 22 affected subjects spanning 3 generations, who had variable degrees of AHO manifestations, with an autosomal dominant inheritance trait. The metacarpophalangeal pattern profile was typical of that of PHP-PPHP. As deficient activity and inactivating mutations of Gs alpha were described in PHP as well as in PPHP, we measured the biological activity of Gs in family members, which was normal. To exclude subtle abnormalities in the Gs alpha gene, we sequenced the entire coding region of Gs alpha in the propositus, which was normal. We conclude that hypocalcemia should be adequately evaluated even in the presence of familial AHO, and that familial AHO can occur with a normal coding structural Gs alpha gene. Identification of the molecular defect in familial AHO without PHP will shed light on the pathogenesis of AHO in general.

Coexisting polyostotic fibrous dysplasia and Paget's disease

The following case report describes a patient who is known to have both fibrous dysplasia and Paget's disease, and traces his history over more than 50 years. The similarities and differences between the two conditions and their relative importance at the various stages of the history are discussed.

Cutaneous fibrous dysplasia: an incomplete form of the McCune-Albright syndrome

A number of genetic disorders have been described in limited form. We report a patient with precocious puberty, large irregularly shaped café-au-lait spots since birth and a diffuse scalp alopecia showing the cutaneous changes of fibrous dysplasia. Histologically, the hair follicles were replaced by convolutions of fibrous tissue. This is to our knowledge the first patient reported with an apparently localized cutaneous form of this syndrome, a pattern predicted by the recently described somatic mutation of the Gs alpha gene. This is the second patient reported to our knowledge with the cutaneous McCune-Albright syndrome and scalp alopecia, and the first with diffuse scalp alopecia, the latter being the presenting sign. We believe that the differential diagnosis of both localized and diffuse alopecia should include the McCune-Albright syndrome.

[Craniomaxillofacial fibrous dysplasias]

Thirty cranio-maxillofacial fibrous dysplasia patients were treated. There were 21 patients with monostotic and 9 patients with multiple lesions both jaws and bones of the skull. Most of the patients were under forty years of age. The lesions caused facial asymmetry in all patients, in two of them was visual disturbances and orbital dystopia, in one patient was hearing loss. The lesions were evaluated histologically that enabled appropriate diagnosis. The principles of surgical treatment were based on the zones of involvement. Treatment was aimed at correcting functional problems and achieving facial aesthetics. Conservative facial aesthetics. Conservative shaving was made in two patients. Radical excision of the dysplastic bone was made in lower parts of the face. In cases of the mandible and maxilla has been made reconstruction with free bone transplants. Tumors of the base of the skull were excised less radically and reconstruction has been made with alloplastic implants. No recurrence or invasion of the fibrous dysplasia into the grafted bone was seen.

Brachydactyly and mental retardation: an Albright hereditary osteodystrophy-like syndrome localized to 2q37

We report five patients with a combination of brachymetaphalangia and mental retardation, similar to that observed in Albright hereditary osteodystrophy (AHO). Four patients had cytogenetically visible de novo deletions of chromosome 2q37. The fifth patient was cytogenetically normal and had normal bioactivity of the alpha subunit of Gs (Gs alpha), the protein that is defective in AHO. In this patient, we have used a combination of highly polymorphic molecular markers and FISH to demonstrate a microdeletion at 2q37. The common region of deletion overlap involves the most telomeric 2q marker, D2S125, and extends proximally for a maximum distance of 17.6 cM. We suggest this represents a consistent phenotype associated with some deletions at 2q37 and that genes important for skeletal and neurodevelopment lie within this region. Screening for deletions at this locus should be considered in individuals with brachymetaphalangia and mental retardation. Furthermore, 2q37 represents a candidate region for type E brachydactyly.

Albright's syndrome: review of the literature and case report

Albright's syndrome is characterized by the presence of polyostotic fibrous dysplasia, endocrinopathies and brown spots on the skin. In the present article the authors describe a case occurring in a 20-year-old female patient, who is currently being followed radiographically after a mandibular bone biopsy.

An activating Gs alpha mutation is present in fibrous dysplasia of bone in the McCune-Albright syndrome

McCune-Albright syndrome (MAS) is a sporadic disease characterized by polyostotic fibrous dysplasia, café-au-lait spots, and multiple endocrinopathies. The etiology of fibrous dysplasia is unknown. Activating mutations of codon 201 in the gene encoding the alpha-subunit of Gs, the G-protein that stimulates adenylyl cyclase, have been found in all affected MAS tissues that have been studied. Initial attempts to amplify DNA from decalcified paraffin-embedded bone specimens from MAS patients were unsuccessful. Therefore, we analyzed DNA from frozen surgical bone specimens from five MAS patients using polymerase chain reaction and allele-specific oligonucleotide hybridization. Most of the cells in four specimens of dysplastic bone contained a heterozygous mutation encoding substitution of Arg201 of Gs alpha with His, but the mutation was barely detectable in peripheral blood specimens from the patients. Only a small amount of mutant allele was detected in a specimen of normal cortical bone from the fifth patient, although this patient had a high proportion of mutation in other, affected tissues. The mosaic distribution of mutant alleles is consistent with an embryological somatic cell mutation of the Gs alpha gene in MAS. The presence of an activating mutation of Gs alpha in osteoblastic progenitor cells may cause them to exhibit increased proliferation and abnormal differentiation, thereby producing the lesions of fibrous dysplasia.

[Clinical variants of McCune-Albright-Braitsev syndrome in girls]

The authors analyze published data on clinical variants and hormonal parameters in patients with this syndrome and present their own observations of children with this condition. Besides early sexual maturation, they describe the clinical picture of Cushing's syndrome, thyroid nodular hyperplasia. The said disorders do not depend on the tropic effect of the hypothalamohypophyseal system. A hypothesis is put forward about primary activation of adenylate cyclase system in the origin of the disease.

An unusual presentation of McCune-Albright syndrome confirmed by an activating mutation of the Gs alpha-subunit from a bone lesion

The McCune-Albright syndrome (MAS) is characterized clinically by polyostotic fibrous dysplasia, café-au-lait skin lesions, sexual precocity, and various other endocrinopathies. Recent investigations suggest an etiological role for embryonic somatic missense mutations that predict the substitution of a His or Cys for Arg at amino acid 201 of the Gs alpha-subunit (Gs alpha). Identification of these mutations in affected tissues is a sensitive assay that may help define a more complete clinical spectrum of the MAS. We investigated a woman who developed fibrous dysplasia 24 yr after premature menstruation. To determine if this was an unusual MAS variant, DNA and RNA were analyzed from affected and unaffected tissues. From samples of affected rib and normal rib DNA was extracted, amplified by polymerase chain reaction, subcloned, and sequenced. RNA was extracted from affected bone, reverse transcribed, amplified by polymerase chain reaction, subcloned, and sequenced. DNA sequence predicting a His for Arg substitution at Gs alpha amino acid 201 was found in 47% of the recombinant plasmids from DNA of affected bone and 17% of the plasmids from DNA of unaffected bone; a significant (P < 0.05) difference in frequency. The His201 substitution was found in 42% of the recombinant plasmids from RNA of affected bone. We conclude that this clinical variant is qualitatively indistinguishable from presentations of the complete MAS.

Melanotic macules following Blaschko's lines in McCune-Albright syndrome

Hyperpigmented macules are a characteristic feature of neurofibromatosis and the McCune-Albright syndrome. Whereas neurofibromatosis 1 has an autosomal dominant mode of inheritance, it has been suggested that McCune-Albright syndrome is the result of a lethal gene surviving by mosaicism. Recent molecular studies have supported this concept by providing evidence of a somatic mutation of the gene encoding the G protein. We report two patients with McCune-Albright syndrome whose melanotic macules show a clear relation to the lines of Blaschko. The lines of Blaschko are thought to represent the dorso-ventral outgrowth of two different cell populations during embryogenesis, thus reflecting genetic mosaicism. A survey of published photographs of patients with McCune-Albright syndrome in the literature revealed additional cases with macules following Blaschko's lines. In other cases, the configuration of the macules was reminiscent of the flag-like rectangular pattern of pigmentation found in human chimaeras. A very early somatic mutation may have similar effects on the pigmentation pattern as a chimaeric state, which is the result of the double fertilization of an ovum. Café-au-lait spots in 10 of our own patients with neurofibromatosis 1 could not be associated with either Blaschko's lines or the rectangular pattern of pigmentation in chimaeras. We conclude that, in contrast with the café-au-lait spots in autosomal dominant neurofibromatosis 1, the configuration pattern of melanotic macules in McCune-Albright syndrome in many cases characteristically reflects the mosaic state of the organism.

Polyostotic coexisting fibrous dysplasia and aneurysmal bone cyst of the chest wall

A case of a 39-year-old woman with a palpable mass in the right hemithorax is presented. The mass had been growing during the last 16 years. Radiographs and computed tomography showed two lesions in the right thoracic wall: the greater was in the anterior and lateral portion of the 7th rib, the minor lesion in the 6th rib costovertebral joint. Both lesions were surgically removed. Histological examination demonstrated the association of fibrous dysplasia and aneurysmal bone cyst in the two lesions. The coexistence of these two lesions supports the theory that aneurysmal bone cyst may represent a secondary change due to haemodynamic alterations of the vascular bed caused by fibrous dysplasia.

Metabolic changes in osteoclasts isolated from children with fibrous dysplasia

Children with fibrous dysplasia have specific areas of local bony overgrowth. The in vitro metabolism of osteoclasts obtained from involved disease areas of two patients with idiopathic monostotic fibrous dysplasia and one patient with polyostotic fibrous dysplasia were compared with osteoclasts isolated from noninvolved bone in the same individuals and normal controls. The osteoclasts from the involved regions formed similar resorption lacunae compared with osteoclasts isolated from both normal and noninvolved bone. Calcium release into the media, a function of cell-mediated resorption, was decreased in involved osteoclasts compared with osteoclasts derived from normal or noninvolved bone (p < 0.05). Osteoclasts from regions of in vivo abnormal growth exhibited normal mineral metabolism in vitro.

Sonography of multinodular thyroid gland in children and adolescents

Multinodular disease of the thyroid gland is uncommon in children and adolescents, and has received little attention in the recent literature. This article reviews the clinical, sonographic, and pathologic findings in 16 children with multinodular disease of the thyroid gland, and draws attention to the high incidence of other associated clinical findings. This condition was associated with a triad including renal and digital anomalies in three patients, with McCune-Albright syndrome in two patients, with Hashimoto's thyroiditis in three patients, and with thyroid carcinoma in four patients. Three of five patients with a history of previous radiation therapy had thyroid carcinoma. Sonography is a proven valuable imaging modality for the study of thyroid disease in children and has contributed to our understanding of multinodular disease of the thyroid gland in this age group.

Acromegaly, multinodular goiter and silent polyostotic fibrous dysplasia. A variant of the McCune-Albright syndrome

A 36-year-old woman is reported with a possible variant of the McCune-Albright syndrome. The triad was incomplete because of the absence of skin pigmentation and since the sexual precocity was not evident. The presence of a pituitary mass and the secretory dynamics of growth hormone and prolactin were suggestive of a mammosomatotroph cell adenoma. A toxic multinodular goiter was also associated, but unique was the spontaneous normalization of the thyroid function. Unusual was the silent evolution of the polyostotic fibrous dysplasia, which was only fortuitously discovered during magnetic resonance imaging of the pituitary region. Treatment of the acromegaly with the long-acting somatostatin analogue octreotide resulted in an important inhibition of the GH secretion and in a reduction of the volume of the pituitary adenoma.