Ablation of osteoid osteomas with a percutaneously placed electrode: a new procedure

Osteoid osteoma is a benign, self-limited tumor of bone that usually requires surgical excision for relief of pain and to prevent long-term consequences. Radio-frequency electrodes have been successfully and safely used to ablate small areas of the central nervous system and to perform ablation elsewhere in the body. The authors have used this technique in four patients with proved or presumptive osteoid osteoma, completely relieving the symptoms in three.

Osteosarcoma resembling osteoblastoma and its heterotransplantation into nude mice

We describe a case of bone tumor in the left tenth rib that was diagnosed as a low-grade osteosarcoma resembling osteoblastoma. This diagnosis was supported by clinical, radiologic, and histologic findings. Specimens of this tumor were transplanted into nude mice, and the morphology of the transplanted tumors was examined. The transplanted tumors were similar histologically to the parent tumor. Ultrastructurally, the transplanted osteoblasts showed irregular, indented nuclei, dilated endoplasmic reticulum, and varying amounts of intercellular junctional complexes. Our transplantable tumor could be valuable as an experimental model for studies on this tumor type.

Osteoid osteoma: radiologic and pathologic correlation

Sixty-seven cases of osteoid osteoma were studied at the Hospital for Joint Diseases between 1980 and 1989. The lesions were categorized according to location: medullary, cortical, or subperiosteal and were further grouped as intracapsular and extracapsular. The histologic features of trabecular thickness, reactive bone formation, proportion of fibrovascular stroma, and ratio of osteoid and mineralized matrix were examined. The radiographic features were compared. The literature is reviewed. We include our experience with tetracycline labelling.

Osteoblastoma of the coccyx. A report of two cases

Osteoblastoma, defined as a benign bone tumor by Jaffe and Lichtenstein, together with osteoid osteoma and multifocal osteoblastoma, belongs to the osteoblastic tumors. Due to the variable features of this tumor, differential diagnosis comprises fibrous dysplasia, giant cell tumor, aneurysmal bone cyst and osteoid osteoma; histological analysis is the only way to obtain a definite answer about the tumor type. Occasionally differential diagnosis from aggressive osteoblastoma and osteosarcoma may be difficult. The history of symptoms is usually long and diagnosis may be difficult both clinically and histologically.

Malignant osteoblastoma versus osteosarcoma: a case report

A 33-year-old male developed a slow-growing mass at the anterior aspect of the left tibia for 8 months. The radiologic finding revealed a well-circumscribed osteolytic mass and appeared benign to most radiologists. The lesion was then excised locally. The histology revealed bizarre osteoblasts and osteoclast-like giant cells interspersing in the vascularized stroma and trabeculated osteoids; the periphery of the lesion showed sclerotic mature bones. Malignant osteoblastoma was, therefore, entertained and the patient was treated as such without aggressive surgery and chemotherapy. He has survived for 11 years. However, the diagnosis of malignant osteoblastoma was still a contradiction because of the presence of cartilage foci.

[The percutaneous removal of osteoid osteomas via CT-guided drilling]

Osteoid osteomas were removed by CT-guided core drill excision of the nidus in 4 patients. All osteoid osteomas were located in the lower extremity and included cortical lesions in the femur (n = 2), and the tibia (n = 1) and one spongious lesion in the navicular bone of the foot. Nidus diameter ranged from 2 to 3 mm. The patients were discharged after the procedure same day or next day depending on the kind of anaesthesia performed. Follow-up periods ranged from 6 to 56 months and revealed no signs of recidivation. CT-guided core-drill excision of the nidus seems to be a very promising alternative to surgical procedures because of its high cost-effectiveness and minimal invasiveness.

Osteoblastoma causing rigidity of the elbow. Case report

A 21-year-old man complained of pain and rigidity of the elbow with a flexion contracture of 100 degrees. A radiographic examination revealed an 1.5-cm osteolytic injury in the center of a sclerotic lesion in the distal humerus. The diagnosis of an osteoblastoma was later confirmed histologically. Once the tumor had been excised, the pain disappeared and functional mobility was reestablished.

Giant cell tumour of the petrous bone

Giant cell tumours (GCT) are rare in the skull bones. In the cranium the sphenoid bone is the most common site. The petrous bone is a very uncommon location for such tumours. The chance location of GCT at the base of the skull makes total surgery difficult and hazardous. A case of GCT of the petrous bone is presented. The clinical course in the patient and role of primary radiotherapy in GCT in such an unusual site is discussed.

Osteoblastoma: a case report and description of the access used to the retromaxillary area

A case of benign osteoblastoma in the retromaxillary region which presented as chronic left sided facial pain of 3 years' duration is reported. The surgical approach to a tumour in this site is difficult and potentially severely mutilating. A transfacial access is described.

Malignant transformation of an osteoblastoma of the skull: an exceptional occurrence. Case report

What is apparently the first reported case of spontaneous malignant transformation of a benign osteoblastoma of the skull is described. The initial lesion was completely removed surgically and showed the histological features typical of a benign osteoblastoma. No radiotherapy was performed. Eleven years later the patient developed an osteosarcoma of the skull. Review of the literature showed that malignant transformation of benign osteoblastomas is extremely rare and could take place spontaneously. However, the risk of this occurring seems higher after inadequate initial treatment (curettage or partial excision). Follow-up monitoring of patients with osteoblastoma of the cranial vault is suggested.

Benign osteoblastoma of the sphenoid bone

Benign osteoblastoma is a rare tumour of bone with a predilection for the spinal column and appendicular skeleton. The skull is an unusual site. We report a case in which the lesion affected the lesser wing of the sphenoid bone and extended from the middle cranial fossa to the orbital region. We discuss the distinguishing features of the tumour, reviewing the literature, and the treatment.

Atypical multiple benign osteoblastomas accompanied by simple bone cysts. A case report

A case of atypical benign osteoblastomas occurring at multiple sites in the maxilla and mandible of a 38-year-old woman, in association with simple bone cysts, is described. The tumors produced hazy or ground-glass-like semiradiolucent lesions with well-defined or poorly-defined margins on conventional radiographs. Histologically, the lesions were characterized by a proliferation of plump osteoblast-like cells forming trabeculae of osteoid and immature bone in a well-vascularized stroma. In addition, simple bone cysts associated with a radiolucent-radiopaque lesion consisting of lamellar bone and loose connective tissue were found next to one of the tumours. Possible pathogenesis of the tumours and cysts is discussed.

[Osteoblastoma of the maxillary sinus. A rare bone lesion?]

The present article reports on a rare case of an osteoblastoma in the maxilla. This tumor usually occurs predominantly in male patients under the age of 30, and is most frequently observed in the femur, tibia, and the vertebrae.

Juxta-articular osteoid osteoma

Osteoid osteomas that arise at the end of a long bone, within the insertion of the joint capsule (juxta-articular, intra-articular), may cause misleading clinical, radiographic, and histologic findings, resulting in unnecessary diagnostic tests and a delay in definitive treatment. To clarify optimum diagnostic procedures, we reviewed 20 cases of juxta-articular osteoid osteomas and found a mean delay from presentation to correct diagnosis of 24 months. Plain radiographs were either negative or showed only secondary changes. A periosteal reaction and proliferative synovitis with chronic inflammation was common, which could be misinterpreted as rheumatoid arthritis. Optimum diagnostic procedures were a bone scan followed by plain tomograms and an excisional biopsy of the nidus.

Benign osteoblastoma of the occipital bone

An uncommon case of benign osteoblastoma of the occipital bone is presented. Poor vascularity of the tumor, as confirmed by the CT scan, operative and histopathological findings, was in contrast to its characteristic high vascularity. Radical resection produced an excellent result.

Osteoid osteoma of the foot

Dr. Wu discusses a benign osteoblastic neoplasm that accounts for less than 3% of all excised tumors. He reviews the symptoms of a 17-year-old, with pathology localized to the third toe. Clinical, radiographic, and histologic characteristics are described.

[Osteoid osteoma of the trapezoid bone]

The present report describes a case of osteoid osteoma of the trapezoid. It'is an unusual localisation. Synovitis was the first clinical symptom. Tomograms allowed diagnosis and guided the treatment. Radical excision prevented recurrence.

Clinicoradiological diagnosis of benign osteoblastoma of the spine in children

Three cases of benign osteoblastoma of the spine in children are reported, diagnosed on the basis of clinicoradiological findings and confirmed at surgery and by histopathology. The authors feel that in all cases of painful scoliosis and painful torticollis, a careful search should be made for any suspicious area of sclerosis, especially in the posterior elements of the vertebrae, and all the positive or suspected cases should undergo nuclear bone scanning. All patients whose bone scan is positive should be subjected to computed tomography for differential diagnosis between osteoid osteoma and benign osteoblastoma.

Aggressive osteoblastoma of the temporal bone: a case report

Osteoblastoma is a rare tumor of bone which is usually present in the long bones and vertebrae. Occasionally, they present in the head and neck, and only very rarely will they have a locally aggressive clinical course. We report a case of the aggressive subtype of benign osteoblastoma and its histologic and radiologic presentation.