Purpose: Hydrogen (H₂) gas inhalation might alleviate acute radiotherapy toxicities by scavenging free radicals produced by ionizing radiation and anti-inflammatory properties. This study aimed to investigate the feasibility and safety of H₂ gas inhalation during concurrent chemoradiotherapy (CCRT) in patients with locally advanced head and neck cancer (LAHNC). Patients and Methods: We designed a pilot prospective study combining CCRT with aerosol inhalation of H₂ gas. Each patient was scheduled to receive daily intensity-modulated radiotherapy (IMRT) in 33 fractions on a weekday and six cycles of weekly chemotherapy. All patients inhaled H₂ gas through a cannula or mask 1 hour per day, 1– 2 hours before IMRT. The primary endpoint was the feasibility of H₂ inhalation. Eighty percent of the patients who completed at least 20 applications of H₂ gas inhalation were considered feasible. The secondary endpoints were safety profiles during H₂ gas inhalation (vital signs and symptoms related to H₂ gas inhalation) and acute toxicities during CCRT. Results: We enrolled 10 patients with LAHNC between July 2023 and December 2023. All patients received 33 fractions of H₂ gas inhalation on the same day as the IMRT. Vital signs during and at the end of H₂ gas inhalation were stable in all patients. None of the 10 patients had hypertension or hypotension during any of the 33 inhalations. No adverse events related to H₂ gas inhalation, such as cough, nasal bleeding, dizziness, headache, nausea, or vomiting, were reported. Grade 3 leukopenia was found in two patients (20%) during the 5th week of CCRT. Grade 2 radiation dermatitis and pharyngitis were found in three patients (30%). Conclusion: H₂ gas inhalation combined with CCRT is feasible and safe for patients with LAHNC.

Background: This study evaluated the efficacy of fluconazole prophylaxis in reducing radiation‐induced oral mucositis (RIOM) and Candida carriage in head and neck cancer (HNC) patients undergoing concurrent chemoradiotherapy (CCRT).Methods: A prospective, double‐blinded, randomized controlled trial was conducted with 78 HNC patients receiving either fluconazole (100 mg daily) or placebo during CCRT. The primary outcome was the incidence of grade 2 or higher RIOM. Secondary outcomes included positive Candida cultures and colony‐forming units (CFUs). Mixed‐effects ordinal logistic regression and logistic regression were used for analysis.Results: Fluconazole significantly reduced the incidence of grade 2 or higher RIOM at week 7 (p = 0.039), positive Candida carriage at week 4 (p = 0.024) and week 7 (p = 0.029), and median CFUs at week 7 (p = 0.050).Conclusions: Fluconazole significantly reduces RIOM severity and Candida colonization in HNC patients undergoing CCRT, suggesting its efficacy as a prophylactic treatment.

Background: Kimura’s disease is a rare inflammatory disease that usually appears in head and neck region. We reported natural history of the disease and treatment outcome of radiotherapy (RT) in Chiang Mai University Hospital. Methods: A retrospective review was performed for all Kimura’s disease patients treated with radiotherapy at our center between 2002 and 2017. Results: A total of 20 patients with Kimura’s disease were reviewed. There were 14 men and 6 women. All patients presented with the mass in head and neck region. Eleven patients were treated with a definitive intent with RT, 9 patients were treated with RT after recurrence from other modalities. All patients were treated with local external beam RT with 2 Gy per fraction to a median total dose of 30 Gy (range 30–40). The median follow-up time was 4 years (range 1–16.5 years). One patient died from HIV opportunistic infection after 1.5 year of radiation with complete response of Kimura’s disease. Most of the patients responded to radiotherapy and controlled the disease at the time of analysis. Two patients had multiple recurrences at new areas outside radiotherapy field. Skin toxicity grade 1 was the most common late side effect which was found in 8 (44%) patients. We did not find severe late toxicity or second malignancy in this patient cohort. Conclusion: Good local control of Kimura’s disease can be achieved, with a radiation dose of 30–40 Gy, with insignificant late toxicities. We suggest that radiotherapy should be one of the treatments of choice for Kimura’s disease both in primary or recurrence setting.

Purpose: The dosimetry of scalp dose was prospectively studied and correlated with alopecia following conventional cranial irradiation in primary brain tumors patients. Materials and methods: Patients with primary brain tumors who required conventional radiotherapy were enrolled. A hairline marker was applied to the patient’s scalp to identify the entire scalp region. The maximal dose to 2% volume of interest (D2) for the entire scalp region were obtained. The radiation dosages at the localized hair-loss areas were evaluated during the final week of RT (transient alopecia) and six months after completing RT (permanent alopecia). Kruskal-Wallis tests were used to compare the dosimetric parameter values with statistical significance set as p < 0.05. Results: Forty-eight patients were included in the analysis. The prescribed radiation doses ranged from 50.4 to 60.0 Gy. Thirty-two patients experienced alopecia (27 transient and 5 permanent). The median D2 values adjusted for the entire scalp were higher in the alopecia group (38.40 Gy for transient alopecia and 47.84 Gy for permanent alopecia vs 11.90 Gy for no alopecia, p < 0.001). The D2 value was determined as a predictive parameter for alopecia. The threshold values for transient and permanent alopecia over the entire scalp were 22.15 Gy and 36.81 Gy, respectively. At the localized hair-loss areas, the D2 values for transient and permanent alopecia were higher at 44.82 Gy and 50.00 Gy, respectively. The radiation intensity at the localized hair-loss areas was also related to the severity of alopecia, with D2 values of 35.14 Gy and 46.39 Gy for clinically assigned grade 1 and grade 2 transient alopecia, respectively, with the D2 value being even higher for permanent alopecia. Conclusions: The D2 parameter value could be used to predict the type and severity of alopecia.