Factors related to risk of recurrence and recurrence free survival in ameloblastoma of the Jaws: A single centre retrospective analysis

Abstract

Purpose: Ameloblastoma is a benign tumor originating from odontogenic epithelium with a global incidence of about 0.5 cases per million persons per year. The overall recurrence rate of ameloblastomas range from 55% -90%. In this retrospective study we have analyzed the factors associated with recurrence and recurrence free survival in ameloblastoma of the jaws.

Methods: Retrospective chart review of 10 years was done from records directory. All demographic data, data on diagnostic modalities, clinical presentations, radiology, management and histology were taken into consideration. Kaplan Meir estimator was used to evaluate recurrence rate and Cox regression analysis (univariate and multivariate) was used to evaluate the odds ratio to find out the possible factors influencing risk of recurrence and influence recurrence free survival. ROC curve (Receiver Operating Characteristic) was used to find out the optimal cut off point for size of the lesion in predicting recurrence. A p value of < 0.05 was considered statistically significant at 95% confidence interval.

Results: A total of 75 patients had recurrence with a median follow up of 65 months. The overall 5 year RFS was 19.5%. Conventional ameloblastomas, cortical/ soft tissue invasion, conservative treatment and tumor size ≥ 4 cm were independent predictors of recurrence.

Conclusion: Aggressive treatment is preferred for conventional ameloblastomas ≥ 4 cm with cortical/ soft tissue invasion.

Keywords: Ameloblastoma; Jaws; Recurrence; Recurrence free survival.