Topical oral cavity chemoprophylaxis using isotretinoin rinse: A 15-year experience

Objectives/Hypothesis: To determine the utility of isotretinoin oral rinses as a method of chemoprevention for recurrent oral cavity squamous cell carcinoma (SCC), carcinoma in situ, and dysplasia. Study Design: Retrospective cohort study. Methods: One hundred forty-three patients were initially enrolled in the study; however, 18 were excluded due to inability to tolerate therapy. The included patients were classified into four groups. Group 1 included patients with multiple early stage oral cavity lesions following initial resection. Group 2 included patients with SCC in situ after excision. Group 3 included patients with multifocal dysplasia following initial CO₂ laser ablation. Group 4 included patients with a history of treated oral cavity SCC with new leukoplakia lesions proven to be dysplastic. Fifty-three patients in the control group did not use post-treatment isotretinoin rinses due to various reasons, whereas 72 patients completed therapy. Minimum use of isotretinoin rinses was 12 months, and minimum follow-up was 24 months. During the follow-up period, all recurrences of carcinoma, in situ disease, and dysplasia were noted and compared with a Fisher test of fit. A Bonferroni correction was applied to increase accuracy and strength of comparison. Results: Using a Bonferroni correction, the significance threshold was 0.0125. By that cutoff, isotretinoin rinses were found to be associated with lower recurrence in groups 1 and 3 (P =.00014, P =.00002, respectively) but not in groups 2 and 4 (P =.4, P =.3846, respectively). Conclusions: Oral isotretinoin as chemoprophylaxis for patients treated for oral cavity squamous cell carcinoma, in situ disease, or dysplasia may be beneficial in decreasing recurrence rate. Level of Evidence: 4. Laryngoscope, 127:1595–1599, 2017.