P496 Effect of fluconazole prophylaxis in prevention of local fungal infections in patients of head and neck cancers receiving chemo-radiotherapy

POSTER SESSION 3, SEPTEMBER 23, 2022, 12:30 PM - 1:30 PM: OBJECTIVES: To ascertain, in head and neck cancer patients receiving chemo-radiotherapy, the efficacy of fluconazole prophylaxis in 1. Reducing the incidence of oropharyngeal fungal infections 2. Reducing the incidence of severe i.e., grade 3 and 4 oropharyngeal mucositis METHODS: A total of 66 cases of Stage III or IV squamous cell carcinoma of the oral cavity or oropharynx who were candidates for radical chemo-radiotherapy (CCRT) were randomly assigned between arm A (study arm) and arm B (control arm) using computer-generated algorithms. Both arms received conventionally fractionated radiation (66-70 Gy) with concurrent weekly intravenous cisplatin (40 mg/m(2)) along with standard measures of oropharyngeal hygiene. In addition, arm A received Tab Fluconazole 100 mg/d administered per oral after lunch from initiation to the completion of radiotherapy, while arm B received Tab Fluconazole 100 mg/d, if fungal infections appeared, for a period of 7-14 days. Weekly clinical examination for oro-pharyngeal candidiasis was done. Throat swabs for microbiological assessment of fungal colonization were done before treatment (zero week), during second and sixth week of CCRT, and 4 weeks after the completion of CCRT, and if any clinical suspicion of fungal infection was present. RESULTS: Proportion of patients who developed fungal infection during treatment was significantly lower in group A—6/33 patients as compared with group B—27/33 patients (18.18% vs. 69.70% respectively, P-value < .0001). Candida albicans was detected in 7 patients (31.82%) while non-albicans Candida was detected in 15 patients (68.18%). Candida parapsilosis, C. tropicalis, C. krusei, and C. glabrata were detected. A total of 3 infected patients (75%) in group A were resistant to fluconazole but showed sensitivity to voriconazole, posaconazole, and caspofungin B. While in group B, 3/18 infected patients (16.66%) showed resistance to fluconazole and these were sensitive to voriconazole, amphotericin B, posaconazole, and caspofungin B. Mean week of onset of fungal infection in group A was 5.5 weeks which was significantly higher as compared with group B of 4.48 weeks (P-value = .029). Proportion of patients who developed grades 3/4 mucositis was significantly lower in group A as compared with group B of 54.55% vs. 81.82% respectively (P-value = .017). Median week of onset of grade 3/4 mucositis in group A was 5.5 weeks which was significantly higher as compared with group B of 5 weeks. (P-value = .029). Proportion of patients with treatment completion was significantly higher in group A as compared with group B—84.85% vs. 60.61% respectively (P-value = .027). Mean number of days needed for treatment completion in group B was 57.55 days which was significantly greater as compared with group A of 50.68 days (P-value =. 033). Median treatment gap in group B was 10 days which was significantly higher as compared with group A of 4 days (P-value = .003). See Figures below. CONCLUSION: Tab fluconazole 100 mg prophylaxis in head and neck cancer patients receiving chemo-radiation is: 1. An effective way to reduce fungal infections, ideal prophylaxis beginning at the fourth week. 2. An effective way to reduce the severity of radiation-induced oral mucositis—thereby translating into reduced morbidity, treatment interruptions, and overall treatment time, which have been shown to impact prognosis favorably.