An underestimated pitfall of oral candidiasis in head and neck cancer patients undergoing radiotherapy: an observation study.

BACKGROUND: Oral candidiasis is a common problem associated with head and neck radiation therapy (RT) consequences being pain, burning sensation, taste change, and systemic infection. There are difficulties in differentiating between oral candidiasis and radiation induced oral mucositis. We conducted a prospective study to explore the incidence of clinical oral candidiasis and evaluate the accuracy of diagnosis among head and neck cancer (HNC) patients receiving RT or concurrent chemoradiotherapy (CCRT). METHODS: This study included 86 HNC patients who had no clinical signs or symptoms of oral candidiasis. Oral mucosa and tongue swabs were carried out and analyzed three times by fungal cultures at the following time points: (1) before RT, (2) at the time of clinically diagnosed candidiasis or during RT at between the 15th-17th fraction (whichever occurred first), and (3) at the end of RT. The accuracy of clinical oral candidiasis was explored and confirmed by fungal colonization techniques. The incidence and risk factors associated with fungal colonization before and throughout the treatment were analyzed. RESULTS: The overall incidence of clinical oral candidiasis was 53.5% throughout the course of RT. Confirmation of fungal colonization was found in 39.5%, 65.9%, and 57.7% of cases before RT, during RT, and end of RT, respectively. The accuracy of the diagnosis using only clinical presentation was demonstrated in 60%, 50%, and 52% before RT, during RT, and end of RT, respectively. Logistic regression analysis showed that age, CCRT, and using 2% viscous lidocaine solution were independent risk factors for fungal colonization. CONCLUSIONS: The results of this study demonstrated an underestimation of clinical oral candidiasis before and throughout the course of radiotherapy from using only clinical sign and symptoms. Crucial attention to detail and testing in the oral examination could improve decision making for detection of oral candidiasis in HNC patients receiving RT or CCRT.

Dosimetric comparison of TomoDirect, helical tomotherapy, and volumetric modulated arc therapy for postmastectomy treatment.

PURPOSE: To compare dose to the targets and organs at risk (OARs) in different situations for postmastectomy patients who require radiation to the chest wall with or without regional nodal irradiation when using three treatment techniques. METHODS AND MATERIALS: Thirty postmastectomy radiotherapy (PMRT) patients previously treated by helical tomotherapy (HT) at our institution were identified for the study. The treatment targets were classified in three situations which consisted of, the chest wall (CW) only, the chest wall plus supraclavicular lymph nodes (CW + SPC), and the chest wall plus supraclavicular and whole axillary lymph nodes irradiation (CW + SPC+AXLN). The volumetric modulated arc therapy (VMAT) plans and Tomodirect (TD) plans were created for each patient and compared with HT treatment plans which had been treated. The target coverage, dose homogeneity index (HI), conformity index (CI), and dose to OARs were analyzed. The quality scores were used to evaluate the appropriate technique for each situation from multiparameter results. RESULTS: The HT and VMAT plans showed the advantage of target coverage and OARs sparing for the chest wall with regional nodal irradiation with the higher plan quality scores when compared with TD plans. However, TD plans demonstrated superiority to contralateral breast sparing for the chest wall without regional nodal situation reaching the highest of planned quality scores. HT plans showed better HI, CI, and target coverage (P < 0.01) than TD and VMAT plans for all patient situations. Volumetric modulated arc therapy plans generated better contralateral breast and heart sparing at a lower dose than HT. CONCLUSION: The arc-based techniques, HT and VMAT plans, provided an advantage for complex targets in terms of target coverage and OARs sparing. However, the static beam TD plan was superior for contralateral organ sparing meanwhile achieving good target coverage for the chest wall without regional node situations.