Benign Bone-Forming Tumors

Benign bone-forming tumors comprise osteomas, osteoid osteomas, and osteoblastomas. Osteomas affect a wide age range and are usually discovered incidentally. They occur predominantly in the craniofacial skeleton and are classically composed of compact bone. Osteoid osteomas and osteoblastomas are painful lesions occurring in young patients. They are morphologically similar and characterized by FOS gene rearrangement and c-FOS expression at a protein level. Osteoid osteomas are usually smaller than 2 cm in maximum dimension with limited growth potential; osteoblastomas are larger than 2 cm and may be locally aggressive. Histologically both are composed of anastomosing trabeculae of woven bone.

Case of Spinal Osteoblastoma in Elderly: Is It Really a Young Patient's Disease?

BACKGROUND

Osteoblastoma is a benign bone-forming tumor, sometimes locally invasive, that may involve any bone. The highest incidence is between 20 and 30 years of age, and there are no cases described in the elderly.

METHODS

We report a case of an elderly patient with a lesion in the lumbar spine in which osteoblastoma diagnosis was made.

CONCLUSIONS

Osteoblastoma is a rare tumor older than 50 years of age, but it should be considered in the differential diagnosis of bone lesions of the spine in adulthood and in the elderly, to avoid a delay in the treatment.

Neurophysiological Monitoring in Radiofrequency Ablation of Spinal Osteoid Osteoma With a Progressive Time and Temperature Protocol in Children

STUDY DESIGN

Retrospective. Level IV Evidence.

OBJECTIVE

To assess the utility of intraoperative neurophysiological monitoring (IONM) to detect and eventually prevent impending neurovascular damage during computed tomography (CT)-guided radiofrequency ablation (RFA) of spinal osteoid osteoma (OO) in children.

SUMMARY AND BACKGROUND DATA

To our knowledge, this is the first case series of spinal OO in pediatric patients treated at a single center employing IONM during RFA.

METHODS

This is a retrospective study of seven consecutive patients (3 girls and 4 boys, mean age: 9 years 4 months) with imaging and clinical signs compatible with spinal OO who underwent CT-guided RFA, under general anesthesia, and IONM in a single center between 2011 and 2015. Before the RFA procedure, a CT-guided percutaneous biopsy of the nidus was performed in the same setting. RFA was divided into four cycles of increasing time and temperature and performed under IONM in every patient.

RESULTS

Two patients had lesions located in the thoracic spine and five patients had lumbar involvement. The RFA technical and clinical success was 85.7%. Six patients presented with reversible neurophysiological changes either during biopsy needle positioning or RFA cycles. In the remaining case, as IONM changes did not improve after several minutes of neuroprotective hypertension, the procedure was interrupted. Neither neurologic nor vascular complications were observed after RFA treatment. In only one biopsy sample, OO was confirmed by histopathologic studies.

CONCLUSION

CT-guided RFA is an accepted minimally invasive technique for the treatment of spinal OO in children. IONM may be a helpful tool that requires minimal additional time and provides feedback on the state of the spinal cord and nerves at risk during the procedure. We promote the use of IONM during these procedures to detect and possibly prevent impending neurologic damage.

LEVEL OF EVIDENCE

Level IV.

Computed tomography-guided percutaneous trephine removal of the nidus in osteoid osteoma patients: experience of a single center in Brazil

Objective

To report the results of computed tomography (CT)-guided percutaneous resection of the nidus in 18 cases of osteoid osteoma.

Materials and Methods

The medical records of 18 cases of osteoid osteoma in children, adolescents and young adults, who underwent CT-guided removal of the nidus between November, 2004 and March, 2009 were reviewed retrospectively for demographic data, lesion site, clinical outcome and complications after procedure.

Results

Clinical follow-up was available for all cases at a median of 29 months (range 6–60 months). No persistence of pre-procedural pain was noted on 17 patients. Only one patient experienced recurrence of symptoms 12 months after percutaneous resection, and was successfully retreated by the same technique, resulting in a secondary success rate of 18/18 (100%).

Conclusion

CT-guided removal or destruction of the nidus is a safe and effective alternative to surgical resection of the osteoid osteoma nidus.