EFFICACY OF THE ENNEKING STAGING SYSTEM IN RELATION TO TREATING BENIGN BONE TUMORS AND TUMOR-LIKE BONE LESIONS

To evaluate the efficacy of the Enneking staging system for determining the prognosis, planning surgical treatment and indicating adjuvant therapy for benign bone tumors (BBT) and tumor-like bone lesions (TBL).

A retrospective multicenter, descriptive, nonrandomized study was carried out on a representative sample comprising a large series of 165 patients with a total of 168 benign bone tumors and tumor-like bone lesions. The patient sample was typical, and matched the literature in all respects. All the patients were classified according to the Enneking staging system, and the initial staging of each lesion was correlated with its behavior after either conservative or surgical treatment, in order to determine the efficacy of the system. The treatment options and complications were described and analyzed.

The results from the treatment provided 95.2% agreement with the Enneking staging system, with a 95% confidence interval of between 90.8 and 97.9%. Of the 168 tumors treated, only eight (4.8%) could not be controlled in relation to the initial treatment indicated by the Enneking staging system. Tumors classified as active were the most prevalent, comprising 73.2% of the lesions. Tumor recurrence was significantly more frequent (p < 0.001) in the aggressive stage. All the patients staged as latent evolved to cure. The study suggested that surgery with wide margins, for aggressive lesions, could provide better lesion control, with a lower recurrence rate (p > 0.001). For latent and active lesions, the study demonstrated the efficacy of both expectant treatment and excision, with or without autogenous bone graft.

The results confirm that the Enneking staging system was very efficient in determining the prognosis, enabling surgical planning and indicating adjuvant therapy for treatment of BBT and TBL.