Case report 351: Aggressive osteoblastoma of the third lumbar vertebra

Osteoid osteoma of a cervical vertebral body

An osteoid osteoma in the anterior part of the body of the fourth cervical vertebra occurred in a 22-year-old female. The patient's main complaint was neck pain and occasional numbness of the extremities. The pain was relieved by analgesics. Plain radiography and a 99Tcm MDP bone scan showed a non-specific abnormality. CT suggested the pathological diagnosis with reasonable certainty. The unusual location of the lesion and the role of various diagnostic modalities are discussed and the literature reviewed.

Osteoblastoma: clinicopathologic study of 306 cases

The clinical, radiologic, and pathologic features of 306 osteoblastomas were analyzed. Seventy-five were Mayo Clinic cases and 231 were from consultation files. Males outnumbered females two to one. The age range was 6 months to 75 years (mean age, 20.4 years). The vertebral column including the sacrum was the most frequent site (32%). Pain was the usual complaint and neurologic findings were associated with vertebral tumors. Although most tumors were well circumscribed, cortical expansion and destruction were common radiographic findings (39%), and 12% had features suggestive of malignancy. Large, epithelioid osteoblasts were seen in 24% and were the predominant cellular element in 10%. A distinctive epithelioid multifocal pattern was recognized. Recurrence rates were 16% (Mayo Clinic cases) and 21% (consultation cases). Tumors involving the central neuraxis were associated with greater morbidity and mortality. Aggressive behavior is within the biologic spectrum of osteoblastomas, and histopathology alone does not appear to be a reliable predictor of aggressiveness. The most important differential diagnosis is osteosarcoma.

Aggressive osteoblastoma of the calcaneus

Aggressive osteoblastoma of the left calcaneus in 29-year-old Japanese woman is reported. Her initial symptom was heel pain while walking. This was a primary calcaneal tumor, initially diagnosed as a benign osteoblastoma. After a 5-year follow-up (from the initial curettage), there was local recurrence. The histologic findings of aggressive osteoblastoma were confirmed after right lower leg amputation. The recurrent tumor was mildly aggressive to the talocalcanean joint and the retrocalcaneal area, without distant metastasis. The characteristics of the primary and recurrent tumors were examined by the radiologic, histologic, and electron microscopic procedures. Although there are questions about aggressive osteoblastoma, the authors believe that there are osteoblastic tumors of borderline malignancy between benign osteoblastoma and low-grade osteosarcoma. The current case was an example compatible with an aggressive osteoblastoma with the proposed name of Dorfman classification Group 4.

Magnetic resonance imaging of vertebral osteoblastoma: a report of two cases

Two patients with vertebral osteoblastoma evaluated with computed tomography and magnetic resonance imaging are presented. A literature review revealed that cases of osteoblastoma originating within the vertebral body are exceedingly rare.

"Aggressive" osteoblastoma of the maxilla

A case of osteoblastoma in the maxilla of a 6-year-old boy is reported. The tumor was clinically characterized by locally aggressive behavior but histologically consisted of a relatively well-circumscribed mass of bone-producing epithelioid osteoblasts and occasional multinucleated osteoclasts characteristic of osteoblastoma. Radiographically the tumor appeared to penetrate the cortical plate. Because of the size of the lesion, its histologic features, and the clinical and radiographic impression of its being poorly confined, the diagnosis of "aggressive" osteoblastoma was rendered. The problem of differentiating between benign and aggressive forms of osteoblastoma is discussed.