Osteoblastoma of the calvaria: report of two cases diagnosed with MRI and clinical review

[Osteoblastoma of the parietal bone of the cranial vault: about a case]

L´ostéoblastome est une tumeur osseuse primitive peu fréquente, sa localisation au niveau de la voûte du crâne est extrêmement rare. Nous rapportons un cas d´ostéoblastome de l´os pariétal droit chez une femme âgée de 46 ans ayant des antécédents de traumatisme crânien bénin. Elle a présenté de façon progressive une tuméfaction pariétale droite douloureuse non inflammatoire. Le scanner crânio-cérébral a montré une lésion osseuse hyperdense respectant la table interne de l´os pariétal droit. La patiente a bénéficié d´abord d´une biopsie puis d´une résection totale de la lésion osseuse avec une cranioplastie au ciment méthyl-méthacrylique. Les suites post-opératoires étaient simples. L´examen anatomo-pathologique a montré qu´il s´agissait d´un ostéoblastome sans signes de malignité. Nous discuterons, à travers notre premier cas d´ostéoblastome de la voûte du crâne et une revue de la littérature, sa présentation clinique, l´examen anatomo-pathologique, les aspects radiologiques, ainsi que la prise en charge de cette rare pathologie.

Aggressive Cranial Osteoblastoma of the Parietotemporo-Occipital Bone: A Case Report and Review of Literature with Special Emphasis on Recurrence/Residue

Osteoblastoma is a rare nonfibroblastic osteoid tissue-forming primary bony tumor usually arising in the medullary cavity/diploic space of any bone. The calvarium is an extremely rare site of its origin. Clinically, 2 types of osteoblastoma are noted: benign/conventional/typical and aggressive/high grade. Their imaging features are nondifferentiating and nonspecific, histopathologic features have a few subtle but nonspecific differences, and they have highly distinct clinical behavior. We report an extremely rare case of a patient with large aggressive cranial osteoblastoma, who developed massive inoperable multifocal recurrence 15 months after total en bloc resection with wide margins. A concise review of cases of aggressive osteoblastomas involving the cranium available in the English literature is also presented as an update.

What's that big thing on your head? Diagnosis of a large frontoparietal lesion on an Eastern Zhou skull from Henan, China

We carried out a differential diagnosis of a large frontoparietal lesion on a human skull from a Late Bronze Age archaeological site located on the Central Plain of China, dating to between 771 and 476 BC. The head of this individual was covered in cinnabar, a mercury-based pigment that later was used for medicinal purposes in China. The lesion was well-circumscribed and involved the outer and inner tables of the skull, slight diploë thickening, and coarsening of bone trabeculae with expansion of intertrabecular spaces. We show that the observed changes are most consistent with cavernous hemangioma of the skull, a benign vascular malformation that preferentially affects older adults. Hemangiomas are often neglected in the paleopathological literature because of their benign nature - they tend to be asymptomatic and do not affect quality of life to a significant degree. Nevertheless, they produce characteristic lesions that can be confused with several other conditions with unrelated etiologies, including congenital hemoglabinopathies, traumas, malignant or benign neoplasms, and Paget's disease. We outline the diagnostic criteria that distinguish cavernous hemangioma from other conditions affecting the skull.

Breast osteoblastoma and recurrence after resection: Demonstration by color Doppler ultrasound

Osteoblastoma is a rare benign primary bone tumor, which occurs in any part of the skeleton. Extraskeletal osteoblastoma is rather rare. We presented an extremely rare case of extraskeletal osteoblastoma located in the breast. The tumor recurred 7 months later after resection and transformed to aggressive osteoblastoma. The histopathological features, ultrasonic manifestations and ultrasonic differential diagnoses of the primary and recurrent tumors were discussed. The recommended treatment of the tumor is surgical excision. Due to its tendency of recurrence and potential malignant transformation, adequate resection and careful follow up is essential.

Imaging characteristics of occipital bone osteoblastoma

Osteoblastoma is a rare benign tumor of the calvarium. We present the case of a 20-year-old female with occipital osteoblastoma and discussion of imaging modalities of calvarial osteoblastoma. To our knowledge, this is the ninth reported case of occipital osteoblastoma. Imaging characterization of osteoblastoma may vary. Plain radiograph, CT, MRI, and CT angiography establish osteoblastoma characterization and vascular supply prior to surgical resection.

The rare aggressive osteoblastoma in a two year old child in an unusual localization

A rare bone tumor of 3rd metacarpal bone in a male child aged 2 years is being described. The patent presented with a gradually increasing, painful swelling over the dorsum of right hand which radiologically revealed an expansile, radioluscent mass, in 3rd metacarpal shaft with cortical destruction. The clinic-radiological differential diagnosis was aggressive cartilage tumor or an osteomyelitis. Histological examination of surgical biopsy material revealed randomly arranged woven bone lined by epithelioid osteoblast and after correlating the clinic-radiological features the diagnosis was an aggressive osteoblastoma. Appropriate diagnosis of such a rare tumor in an unusual location and age group facilitate adequate management by surgery alone without radiotherapy or chemotherapy.

An enlarged parietal foramen in the late archaic Xujiayao 11 neurocranium from Northern China, and rare anomalies among Pleistocene Homo

We report here a neurocranial abnormality previously undescribed in Pleistocene human fossils, an enlarged parietal foramen (EPF) in the early Late Pleistocene Xujiayao 11 parietal bones from the Xujiayao (Houjiayao) site, northern China. Xujiayao 11 is a pair of partial posteromedial parietal bones from an adult. It exhibits thick cranial vault bones, arachnoid granulations, a deviated posterior sagittal suture, and a unilateral (right) parietal lacuna with a posteriorly-directed and enlarged endocranial vascular sulcus. Differential diagnosis indicates that the perforation is a congenital defect, an enlarged parietal foramen, commonly associated with cerebral venous and cranial vault anomalies. It was not lethal given the individual’s age-at-death, but it may have been associated with secondary neurological deficiencies. The fossil constitutes the oldest evidence in human evolution of this very rare condition (a single enlarged parietal foramen). In combination with developmental and degenerative abnormalities in other Pleistocene human remains, it suggests demographic and survival patterns among Pleistocene Homo that led to an elevated frequency of conditions unknown or rare among recent humans.

Benign osteoblastoma of the ethmoid sinus

Osteoblastoma is categorized as a benign bone-forming tumor, which occurs rarely in the craniofacial region. We report a case of osteoblastoma developed in the nasal cavity and ethmoid sinus in a 14-year-old girl whose chief symptom was nasal obstruction and exophthalmos on the right side. CT revealed the lesion having the same density as bone and a ground-glass border, expanding to the nasal and paranasal cavities. Complete removal was accomplished under endoscopic view, although the tumor was removed piece by piece. Histologic inspection showed exuberant osteoid trabeculae and immature bone formation by osteoblasts with vascularized connective tissue. We diagnosed the tumor as osteoblastoma based on the clinical presentation and the size of the tumor. No recurrence was evident at the 1-year follow-up visit.

Antemortem trauma and survival in the late Middle Pleistocene human cranium from Maba, South China

Paleopathological assessment of the late Middle Pleistocene archaic human cranium from Maba, South China, has documented a right frontal squamous exocranially concave and ridged lesion with endocranial protrusion. Differential diagnosis indicates that it resulted from localized blunt force trauma, due to an accident or, more probably, interhuman aggression. As such it joins a small sample of pre-last glacial maximum Pleistocene human remains with probable evidence of humanly induced trauma. Its remodeled condition also indicates survival of a serious pathological condition, a circumstance that is increasingly documented for archaic and modern Homo through the Pleistocene.

Benign osteoblastoma of the sphenoid bone

Osteoblastoma is an uncommon benign bone tumor that accounts for 1% of all primary bone tumors. Well documented in the spine and long bones, it is rarely found in the skull, namely in the sphenoid bone, with only five cases reported in the literature. We report a case of an 11-year-old girl with a histologically confirmed benign osteoblastoma in an unusual location and an atypical aspect on the imaging studies.

Primary pediatric skull tumors

BACKGROUND/AIMS

To review the pathological distribution of pediatric primary skull tumors, and to determine the diagnostic value of lesion location, patient age and lesion size.

METHODS

A retrospective chart review identified 51 consecutive pediatric patients with 54 primary skull tumors, treated between 2005 and 2010.

RESULTS

The most common diagnoses were dermoid cysts (n = 34) and fibrous dysplasia (n = 5). While dermoid tumors could reside anywhere (sensitivity = 0.41), a midline lesion had a specificity of 0.9 and a positive predictive value of 0.88. All of the fibrous dysplasia lesions were laterally placed, with a negative predictive value (NPV) of 1. Patient age < or >5 years had a high sensitivity and NPV for dermoid cysts and fibrous dysplasia, respectively. Size appeared to be sensitive (0.91, 0.8), but not specific (0.6, 0.78), with good NPV (0.8, 0.97) when considering dermoid cysts (≤2 cm) or fibrous dysplasia (>2 cm), respectively.

CONCLUSION

Dermoid cysts followed by fibrous dysplasia are the most common primary skull tumors. Lesion location, patient age and lesion size give important clues as to the diagnosis. For the majority of cases, a clinical diagnosis based on CT is sufficient for presurgical evaluation.

Benign osteoblastoma located in the parietal bone

Benign osteoblastoma is an uncommon primary bone tumor, extremely rare in calvarium. We present a case of a 25-year-old female with an osteoblastoma of parietal bone which was totally resected. The authors discussed the clinical presentation, radiographic finding, differential diagnosis and management of the benign calvarial osteoblastoma with a review of the literature.

Imaging of the unusual pediatric 'blastomas'

‘Blastomas’ are tumors virtually unique to childhood. Controversy surrounds their nomenclature and there is no globally accepted classification. They are thought to arise from immature, primitive tissues that present persistent embryonal elements on histology, affect a younger pediatric population and are usually malignant. The ‘commoner’ blastomas (neuroblastoma, nephroblastoma, hepatoblastoma, medulloblastoma) account for approximately 25% of solid tumors in the pediatric age range. We present examples of the more unusual blastematous pediatric tumors (lipoblastoma, osteoblastoma, chondroblastoma, hemangioblastoma, gonadoblastoma, sialoblastoma, pleuropulmonary blastoma, pancreatoblastoma, pineoblastoma, and medullomyoblastoma) that were recorded in our institution. Although these rare types of blastomas individually account for <1% of pediatric malignancies, collectively they may be responsible for up to 5% of pediatric tumors in a given population of young children. Imaging is often non-specific but plays an important role in their identification, management and follow-up. Some characteristic imaging features at diagnosis, encountered in cases diagnosed and treated in our institution, are described and reviewed.

Primary Skull Lesions in the Pediatric Population: A 25-Year Experience

Context.—Primary skull lesions are rare in the pediatric population. The differential diagnosis of these lesions is broad and includes both congenital and acquired lesions. Previous studies of skull lesions in the pediatric population suggest that dermoid/epidermoid tumors are the most common childhood skull tumors.

Objective.—To review the clinicopathologic features of primary skull lesions identified within the pediatric population of an academic tertiary medical center.

Design.—A retrospective review of surgical pathology reports during a 25-year period identified 19 primary skull lesions occurring in the pediatric population. Lesions were excluded if they were of known soft tissue or intracranial origin with secondary calvarial involvement, or if they represented a metastasis from a known primary malignancy.

Results.—Nineteen primary skull lesions were identified in 11 male (58%) and 8 female (42%) patients, with a median age at diagnosis of 9.5 years. These lesions were usually benign and most commonly presented as a painless mass (n = 8). The lesions were located in the occipital bone (n = 7), frontal bone (n = 5), parietal bone (n = 2), and temporal bone (n = 1). Diagnoses included epidermoid/ dermoid cyst (n = 8), Langerhans cell histiocytosis (n = 6), intraosseous hemangioma (n = 2), osteoblastoma (n = 1), infantile myofibroma (n = 1), and fibroma (n = 1). Intracranial extension was identified in 1 case, and recurrence was found in only 2 cases.

Conclusions.—Epidermoid/dermoid cysts and Langerhans cell histiocytosis are the most commonly encountered skull lesions in the pediatric population at our institution. Intracranial extension of these lesions is rare, and recurrence is uncommon following complete surgical resection.

Benign osteoblastoma of the occipital bone: case report and literature review

We present a case of benign osteoblastoma of the occipital bone. Benign osteoblastoma is an uncommon primary bone tumor, which usually involves the vertebrae and the long bones. This tumor rarely develops in the calvaria, showing a preference for the temporal and frontal bones when it does. To the best of our knowledge, this case is only the eighth reported case of benign osteoblastoma confined to the occipital bone. A 20-year-old male presented with a mild tender mass lesion of the occipital area, just below the lambda. Plain X-ray films and CT scans demonstrated an osteolytic mass surrounded by the sclerotic rim within the diploic space. MRI proved to be effective for the evaluation of the intracranial and intraosseous extensions of the tumor. However, it was very difficult to formulate a differential diagnosis against other osteoblastic tumors, or osteoid osteoma, in view of its radiological appearance. The final diagnosis was obtained by careful consideration of the histopathological characteristics of the tumor combined with its clinical and radiological features. Although generally regarded as benign, a complete resection is preferred over conventional curettage as this can guard against possible recurrence and malignant transformation.

Benign fronto-orbital osteoblastoma arising from the orbital roof: case report and literature review

BACKGROUND

Osteoblastoma is an uncommon benign osteogenic neoplasm that rarely involves the orbit. Intracranial and intraorbital extension causing neurologic and ophthalmologic symptoms and signs is very unusual. We report the case of an osteoblastoma of the orbital cavity with ethmoidal and anterior cranial fossa extension presenting as unilateral proptosis. Manifestations and management of this rare fronto-orbital lesion are discussed, and the relevant literature is reviewed.

CASE DESCRIPTION

This 22-year-old man experienced a 3-month history of progressive left proptosis without neurologic symptoms. Computed tomography and magnetic resonance imaging scans demonstrated a bony mass involving the roof of the left orbit and extending laterally to the adjacent ethmoid cells and upward to the lower part of the homolateral frontal convexity without parenchymal abnormality. A presumptive diagnosis of osteoma was considered. A left fronto-orbital craniotomy was performed. At surgery, the tumor was well circumscribed by a sclerotic margin. It was granular with bony spicules, destroying the orbital roof and involving the orbital cavity, ethmoidal cells, and anterior cranial fossa. The lesion was totally removed, and the anterior cranial base reconstructed. The histologic features were typical of benign osteoblastoma. After a follow-up period of 12 months, the patient has remained well without evidence of recurrence.

CONCLUSION

Osteoblastoma should be considered in the differential diagnosis with other fronto-orbital bone-forming lesions. Although generally regarded as benign, a complete resection is recommended to prevent the possibility of postoperative recurrence and malignant transformation. Twelve previously reported cases were also reviewed.