How Does 5-Fluorouracil Fare as an Adjunct to Enucleation and Peripheral Ostectomy in the Treatment of Odontogenic Keratocysts at 1-year Follow-up?

Background Very few studies have been done to evaluate bone healing in odontogenic keratocysts (OKCs) after surgical treatment along with 5-fluorouracil (5-FU) application. Purpose To evaluate bone healing following treatment of OKC with enucleation, peripheral ostectomy, and 5-FU using cone beam computed tomography (CBCT) at 6 months and 1 year postoperatively. Secondary objectives were to evaluate recurrence after 6 months and 1 year and to evaluate complications. Study Design, Setting, and Sample Prospective observational study on 20 patients with biopsy-proven OKCs in a tertiary care government hospital was conducted. Predictor/Exposure/Independent Variables Age, gender, number of cysts, side involved, chief complaint, syndromic or not, cystic dimension in cm 3 , teeth involved, bone density in Hounsfield units (HU), teeth extracted, nerve involvement, and use of prophylactic intermaxillary fixation. Main Outcome Variables Primary outcome variables were size of cavity and bone formation in HU. Secondary variables were recurrence and incidence of postoperative complications. Covariates Demographic covariates included age, gender, side involved, and chief complaint. Radiographic covariates were the preoperative size of the lesion in cm 3 and the cortical breach evident on CBCT. Operative covariate was inferior alveolar nerve involvement. Analyses Wilcoxon signed rank test, P value < .001. Results In total, 20 patients were included. Four patients were lost to follow-up after 6 months. Mean age of patients was 32.3 ± 10.4 years with a male-to-female ratio of 3:2. Median (interquartile range, IQR) density of lesions on the unoperated side was 374.61(251.69-529.49) HU. Median (IQR) density values of lesions preoperatively, 6 months, and 1 year postoperatively ( N = 16) were 1.35(−39.21 to 24.68) HU, 169.31(72.61-290.26) HU, and 378.31(141.33-559.83) HU. Recurrence rate was 0%. Mean (visual analog scale, VAS) values on days 1 and 7 and 1 month postoperatively were 3.9 ± 1.8, 1.75 ± 1.68, and 0.4 ± 0.94. There was a 40% incidence of sensory disturbance at 1 month and 15% at 6 months and 1 year; 70% incidence of dehiscence, 25% infection, and 5% each for osteomyelitis and pathologic fracture. Conclusions and Relevance Bone density was comparable to that of unoperated normal bone at 1 year postoperatively. No recurrence was noted. Theoretical concerns for 5-FU, being an antimetabolite with possible negative effects on bone remodeling, make these study results relevant.