308P - Dental prophylaxis and 5-fluorouracil related oral mucositis in head and neck cancer patients: A population-based cohort study

Background

It is hard to prevent 5-fluorouracil (5-FU) related oral mucositis (OM). The aim of this study was to determine the association between dental prophylactic modalities and the risk of OM in HNC patients with 5-FU-related treatment.

Methods

During 2000 to 2008, 20,715 HNC (ICD-9-CM 140-149) patients with newly 5-FU-related chemotherapy were selected from the registry of LHID-CIP, and the date of 5-FU therapy initiation was defined as the index date. These HNC patients were stratified into three groups according to their cancer locations: oral cancers (ICD-9-CM 140-145), nasopharyngeal cancer (NPC, ICD-9-CM 147) and other cancers (ICD-9-CM 146, 148 and 149).The end date was defined as the date of OM diagnosis, withdrawal from the NHI program, or the 21^thday after the day of 5-FU therapy initiation, whichever came first. Patients with OM diagnosis (ICD-9 CM 528.00, 528.01, 528.2, and 528.9). The records of dental treatment was determined for each patient within 180 days prior to the index date, which included fluoride gel application, chlorhexidine mouth rinse, scaling, and major oral surgery. Based on the different dental prophylactic modalities, all HNC subjects were stratified into different groups. Odds ratios (OR) and 95% confidence intervals (CI) were determined by multiple logistic regression model.

Results

13,969 HNC participants, including 482 5-FU-related OM subjects and 13,487 controls were enrolled. Fluoride gel application and scaling were significantly related to OM development (p < 0.001). 2.25-fold increased risk of OM while scaling was performed within three weeks before 5-FU-related chemotherapy (95% CI = 1.81–2.81), and a 3.22-fold increased risk of OM while fluoride gel was applied during 5-FU-related treatment (95% CI = 1.46–7.13).

Conclusions

This study highlighted a remarkable association between dental prophylactic modalitiesand the risk of 5-FU-related OM in HNC population.Clinical practitioners have to be vigilant about the joint effect of scaling and fluoride gel application in the increased risk of OM. Optimal timing of scaling and appropriate fluoride gel application strategy are necessary in reducing the risk of 5-FU-related OM.

Clinical trial identification

Editorial acknowledgement

This study is supported in part by Taiwan Ministry of Health and Welfare Clinical Trial and Research Center of Excellence (MOHW105-TDU-B-212-133019), China Medical University Hospital, Academia Sinica Taiwan Biobank Stroke Biosignature Project (BM10501010037), NRPB Stroke Clinical Trial Consortium (MOST 105-2325-B-039-003), Chang Gung Memorial Hospital (CMRPG3I0151), Far Eastern Memorial Hospital (FEMH-2019-C-039), Tseng-Lien Lin Foundation, Taichung, Taiwan, Taiwan Brain Disease Foundation, Taipei, Taiwan, and Katsuzo and Kiyo Aoshima Memorial Funds, Japan.

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.