George Loria

Osteoid osteoma is a benign osteoblastic tumor characterized mostly by presence of one nidus, butvery infrequentlyniduses can be multiple. Radiofrequency ablation is a well-established treatment method for this disease. We report a case of a 19-year-old male patient with bifocal osteoid osteoma which was partially missed on the initial magnetic resonance imaging and treated successfully with two sessions of radiofrequency ablation. Following the second session of ablation, the pain resolved immediately and the patient remains pain-free for 6 months since the procedure. Our case report underlines the fact that although very rare, multifocal osteoid osteomas do exist and its niduses can be obscured during the magnetic resonance imaging due to the edema. It emphasizes the role of the initial computed tomography evaluation.

The incidence of Aneurismal Bone cyst has increased in worldwide. ABC-like lesions involving Giant (GCTOB) cells, fibrohistiocytic or tumor FD like components can confuse pitfalls of ABC and need to observe and defines. We investigated tissue resources from operative materials of total 28 cases of ABC, selected as primary ABC without any bone pathology (n=17) and ABC-like changes accompanying by Giant cell tumor (n=9) and Fibrous dysplasia (FD) (n=2). Female – 10, male – 18, mean age - 27. Cases were reported according clinical, radiological, histological, localization and recurrence features with special attention to immunohistochemistry (IHC) using different markers: P53, Bcl-2, P63, Ki-67, CD68, Cyclin D1. The results of these assessments were compared for the final histologic diagnosis. Results show that IHC has a positive value in dysplastic and cancerous stroma in GCTOB (P63, Cyclin D1); FD field does not show similar activity, demonstrating improved diagnostic accuracy.