Cancer Treatment Today

Osteoid osteoma is a benign osteoblastic tumor. The literature suggests a history of resolving pain and healing of the lesions, but the course can be variable. The course of this disease is unpredictable and protracted, with intervals of resolution of pain that sometimes last 6-15 years. Initial treatment of osteoid osteoma remains non-operative, with medications consisting of aspirin or other NSAIDs. There is a variety of operative approaches. Surgical intervention is generally indicated for patients whose pain is unresponsive to medical therapy, patients who cannot tolerate prolonged use of NSAIDs, and those who are not amenable to activity restrictions.

Percutaneous radiofrequency coagulation or ablation of the nidus is performed by using an electrode placed in the lesion, coupled with a radiofrequency generator that produces local tissue destruction by converting radiofrequency into heat. Complete or nearly complete relief of pain often occurs within 3 days. Patients are sent home on same day of surgery, and they have no limitations in weight bearing, though aggressive athletics are restricted for 2-3 months. Patients may then return to normal activities immediately or within 24-48 hours after surgery. For this reason, it is currently the favored procedure for osteoblstic osteoma. Pain resolves immediately, and limping resolves within 24 hours. Furthermore, this procedure requires only a small osseous access to allow insertion of the electrode; therefore, no substantial structural weakening of the bone occurs. Primary cure rates are 83-94%.

The main disadvantages of this procedure are recurrence or persistence of the osteoid osteoma and the lack of histologic verification. Recurrent lesions can be managed with repeat percutaneous radiofrequency ablation, but lesions should be confirmed histologically by means of needle biopsy before ablation. Cure with a second ablation procedure is approximately 100% and recurrence is very rare. Lesions that are resistant to percutaneous radiofrequency ablation can easily be treated with open surgery. Another complication is local skin burns.

I had not been able to find guidelines that recommend RFA or comparative studies of surgery versus RFA. However, the literature appears to support RFA as the lass invasive and somewhat preferable option. For example a recent article (Montanez-Heredia et al) says: “CT-guided radiofrequency ablation of osteoid osteoma is neither invasive nor damaging. It has achieved a high rate of pain relief with a small morbidity rate in this series. It can be carried out on a one-day clinic basis. In cases in the lower extremity, immediate full-weight bearing is allowed following the procedure. Open surgery should be used only for cases in which the diagnosis is uncertain, or when the lesion is located near an important neurovascular structure and cannot be removed completely

Motamedi D, Learch TJ, Ishimitsu DN, Motamedi K, Katz MD, Brien EW, et al. Thermal ablation of osteoid osteoma: overview and step-by-step guide. Radiographics. Nov 2009;29(7):2127-41. [Medline].

Akhlaghpoor S, Aziz Ahari A, Ahmadi SA, Arjmand Shabestari A, Gohari Moghaddam K, Alinaghizadeh MR. Histological evaluation of drill fragments obtained during osteoid osteoma radiofrequency ablation. Skeletal Radiol. May 2010;39(5):451-5.

Volkmer D, Sichlau M, Rapp TB. The use of radiofrequency ablation in the treatment of musculoskeletal tumors. J Am Acad Orthop Surg. Dec 2009;17(12):737-43.

Rehnitz C, Sprengel SD, Lehner B, Ludwig K, Omlor G, Merle C, et al. CT-guided radiofrequency ablation of osteoid osteoma: correlation of clinical outcome and imaging features. Diagn Interv Radiol. Mar 8 2013

 Elvira MONTAÑEZ-HEREDIA, José SERRANO-MONTILLA, María Luisa MERINO-RUIZ,

Francisco AMORES-RAMÍREZ, José VILLALOBOS-MARTÍN Osteoid osteoma : CT-guided radiofrequency ablation Acta Orthop. Belg., 2009, 75, 75-80

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