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Aims: This study aims at assessing the volume changes that occur in the targets (gross tumor volume and planning target volume [PTV]) and the organs at risk in squamous cell carcinoma of the head and neck during radiotherapy and assessing the dose changes that occur as a result of them. Settings and Design: This was a prospective observational study in a tertiary care center after obtaining the appropriate scientific and ethics committee clearance. Subjects and Methods: Forty-five patients diagnosed with squamous cell carcinoma of the head and neck, who were treated with intensity-modulated radiotherapy in the time period from March 2018 to May 2019, were enrolled in the study. A planning computed tomography (CT) scan (CTplan) was done for all patients, followed by scans after 15 fractions (CT15) and after 25 fractions (CT25). The volume changes and the subsequent dose changes were assessed and recorded. Statistical Analysis Used: Data entry was done in MS Excel spreadsheet. The continuous variables were expressed as mean + standard deviation. The comparison of normally distributed continuous variables was done by paired t-test. Data analysis was done by SPSS (Statistical Package for the Social Sciences) version 16.0. P < 0.05 was considered statistically significant. A multivariate linear regression model was constructed to study the correlation between mean dose to the parotid glands and the other variables. All statistical modeling and analysis were done using SAS (Statistical Analysis Software) version 9.4. Results: Of the 45 patients, 25 were male and 20 were female. The majority of the patients had malignancies in the oral cavity (16) and hypopharynx (14). Most of them had Stage III/IV (AJCC v 8) disease (41). There were a 36% decrease in the PTV-high risk (PTV-HR) volume and a 6.05% decrease in the PTV-intermediate risk (PTV-IR) volume CT15. In CT25, the volume decrease in the PTV-HR and the PTV-IR was 47% and 9.06%, respectively. The parotid glands also underwent a reduction in their volume which has been quantified as 21.7% and 20.9% in the ipsilateral and contralateral parotids in CT15 and 36% and 33.6% in CT25, respectively. The D2 (dose received by 2% of the volume) and D98 (dose received by 98% of the volume) of the PTV-IR showed changes of +3.5% and –0.2% in CT15 and + 4.6% and –0.31% in CT25, respectively. The homogeneity index and conformity number of the PTV-IR changes by 0.03 and 0.08 in CT15 and by 0.04 and 0.12 in CT25, respectively. The mean dose to the ipsilateral parotid gland increased by 14% in CT15 and 19% in CT25. The mean dose to the contralateral parotid gland increased by 17% in CT15 and 25% in CT25. Conclusion: The dose to the parotid glands increases as a result of the changes that occur during the course of radiation. The changes are significant after 15 fractions of radiation. A replanning at this juncture might be considered to reduce the dose to the parotid glands
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Abstract Introduction To manage the complications of irradiation of head and neck tissue is a challenging issue for the otolaryngologist. Definitive treatment of these complications is still controversial. Recently, hyperbaric oxygen therapy is promising option for these complications. Objective In this study, we used biochemical and histopathological methods to investigate the efficacy of hyperbaric oxygen against the inflammatory effects of radiotherapy in blood and laryngeal tissues when radiotherapy and hyperbaric oxygen are administered on the same day. Methods Thirty-two Wistar Albino rats were divided into four groups. The control group was given no treatment, the hyperbaric oxygen group was given only hyperbaric oxygen therapy, the radiotherapy group was given only radiotherapy, and the radiotherapy plus hyperbaric oxygen group was given both treatments on the same day. Results Histopathological and biochemical evaluations of specimens were performed. Serum tumor necrosis factor-α, interleukin-1β, and tissue inflammation levels were significantly higher in the radiotherapy group than in the radiotherapy plus hyperbaric oxygen group, whereas interleukin-10 was higher in the radiotherapy plus hyperbaric oxygen group. Conclusion When radiotherapy and hyperbaric oxygen are administered on the same day, inflammatory cytokines and tissue inflammation can be reduced in an early period of radiation injury.
Resumo Introdução O manejo das complicações da irradiação do tecido da cabeça e pescoço é uma questão desafiadora para o otorrinolaringologista. O tratamento definitivo dessas complicações ainda é controverso. Recentemente, a oxigenoterapia hiperbárica tem sido uma opção promissora para essas complicações. Objetivo Nesse estudo foram usados métodos bioquímicos e histopatológicos para investigar a eficácia do oxigênio hiperbárico contra os efeitos inflamatórios da radioterapia no sangue e nos tecidos laríngeos, quando a radioterapia e oxigênio hiperbárico são administrados no mesmo dia. Métodos Trinta e dois ratos Wistar albinos foram divididos em quatro grupos. O grupo controle nao recebeu tratamento, o grupo de oxigenio hiperbarico recebeu apenas oxigenoterapia hiperbarica, o grupo de radioterapia recebeu apenas radioterapia e o grupo de radioterapia com oxigenio hiperbarico recebeu ambos os tratamentos no mesmo dia. Resultados Foram realizadas avaliaçoes histopatologicas e bioquimicas dos especimes. Os niveis sericos de fator de necrose tumoral-α, interleucina-1β e inflamaçao tecidual foram significativamente maiores no grupo de radioterapia do que no grupo de radioterapia mais oxigenio hiperbarico, enquanto que a interleucina-10 foi maior no grupo de radioterapia mais oxigenio hiperbarico. Conclusão Quando a radioterapia e o oxigênio hiperbárico são administrados no mesmo dia, as citocinas inflamatórias e a inflamação tecidual podem ser reduzidas no período inicial da radiação.