A novel method to evaluate salivary flow rates of head and neck cancer patients after radiotherapy: a pilot study

Antibiotic therapy for the prevention of osteoradionecrosis following tooth extraction in head-and-neck cancer patients postradiotherapy: An 11-year retrospective study

Introduction:

One of the most important complications of radiotherapy (RT) for head-and-neck cancer (HNC) is osteoradionecrosis (ORN) of the jaws, which mostly arises from tooth extractions. The ORN treatment still represents a great challenge; therefore, the prevention is of paramount importance. Thus, the present study aimed to evaluate retrospectively a perioperative systemic antibiotic therapy protocol for the prevention of ORN following tooth extraction in head-and-neck patients post-3D conformal RT.

Materials and Methods:

A retrospective medical record review was performed considering HNC patients submitted to RT in the period between 2008 and 2019. They necessarily received oral antibiotic therapy with Clindamycin 300 mg every 8 h for 10 days, with the first dose 3 days before the tooth extraction.

Results:

Forty-nine patients met the study criteria, with a total of 107 teeth extracted. Regarding the 47 patients who did not develop ORN, 103 tooth extractions were identified (96.3%). Only two patients developed ORN at two adjacent teeth sites (3.7%).

Conclusion:

The proposed perioperative systemic antibiotic therapy protocol seems to be efficient to prevent ORN following tooth extraction in postirradiated HNC patients.

Unstimulated salivary flow and oral streptococci in pediatric patients with hematological tumors: A longitudinal study

AIMS

To evaluate the unstimulated salivary flow (USF) and salivary colonization of total Streptococcus spp. (TS) and mutans-group (MS) in pediatric patients with hematological tumors. Correlations of salivary and microbiological changes with chemotherapy and patient-related factors were also verified.

METHODS AND RESULTS

Eligible children (n = 31) were evaluated before (control) and after (2, 5, and 10-weeks) the chemotherapy protocol was applied. Saliva samples were collected by the traditional spitting method to determine the USF (ml/min). Salivary TS and MS were determined by colony-forming units (CFU ) counts in a selective medium. The caries experience was evaluated by DMFT/dmft indexes. Data were submitted to Student's t-test, one-way ANOVA, and correlation tests (α = 0.05). The USF rate at baseline was 0.89 (±0.73) ml/min with up to 20% reduction during the follow-up and did not differ statistically during chemotherapy (p  > .05). Chemotherapy did not modify the salivary TS load (p > .05), but induced a dysbiotic shift with higher MS counts (∼ 5 fold-increase) at 10-weeks (p < .05). There is a correlation of USF with age (r = .390) and SM load with caries experience (r_s  = -.540) at 5-weeks.

CONCLUSION

Chemotherapy may promote a specific increase of mutans-group streptococci without changing the Streptococcus spp. load and unstimulated saliva flow. Correlation reinforced the need for further enlightenment about the chemotherapy mechanisms in the salivary and microbiological parameters.

Exploring the Interplay Between Radiotherapy Dose and Physiological Changes in the Swallowing Mechanism in Patients Undergoing (Chemo)radiotherapy for Oropharynx Cancer

This study explored associative relationships between radiotherapy dose volumes delivered to the dysphagia aspiration risk structures (DARS) and swallowing physiological disturbance at 3 months post treatment in a homogenous cohort of patients who received (chemo)radiotherapy ((C)RT) for oropharyngeal head and neck cancer (HNC). Participants(n = 53) were a subgroup of patients previously recruited as part of a prospective randomised trial, and had undergone physiological swallowing assessment using videofluroscopic swallowing study (VFSS) at 3 months post (C)RT. The extended oral cavity (EOC), supraglottic larynx (SGL), glottic larynx (GL), cricopharyngeal inlet (CI), and pharyngeal constrictor muscles (PCM) were contoured as per international consensus guidelines and dose volume histograms (DVHs) were generated for each structure. Each DVH was analysed to reveal mean, maximum and partial radiotherapy doses of V₄₀, V₅₀ and V₆₀ for each structure. Physiological swallowing function on VFSS was rated using the Modified Barium Swallow Impairment Profile (MBSImP). A binary logistic regression model was used to establish associative relationships between radiotherapy dose to the DARS and physiological changes within the swallowing mechanism. Structures that received the largest volumes of radiotherapy dose were the PCM and SGL. Significant relationships were found between the proportion of the EOC, SGL, GL and PCMs that received radiotherapy doses > 40 Gy, > 50 Gy and > 60 Gy and the likelihood of a moderate-severe physiological swallowing impairment (on the MBSImP). Whilst the current study was exploratory in nature, these preliminary findings provide novel evidence to suggest structure-specific associative relationships between radiotherapy dose and impacts to corresponding swallow physiology in patients with oropharyngeal HNC.

Does laser photobiomodulation prevent hyposalivation in patients undergoing head and neck radiotherapy? A systematic review and meta-analysis of controlled trials

INTRODUCTION

Head and neck radiotherapy can cause hypofunction of the salivary glands. Many studies report that laser photobiomodulation (PBM) is able to minimize radiation-induced hyposalivation, yet there is no consensus about its effects.

OBJECTIVE

To carry out a meta-analysis of controlled clinical trials that used PBM to prevent radiation-induced hyposalivation.

METHODS

A systematic search was performed through Embase, Medline/PubMed, Cochrane, EBSCO, Scopus, LILACS and Web of Science databases. The strategy included comparisons of the effect of PBM with placebo/clinical follow-up on unstimulated and/or stimulated salivary flow in patients undergoing head and neck radiotherapy.

RESULTS

Six clinical trials were included, five of which were used for meta-analysis. Evidence was observed between the use of PBM and increased unstimulated salivary flow (MD 0.20 mL/min, 95 % Cl 0.10-0.30, I² = 96 %, p < 0.00001) and in stimulated salivary flow (MD 0.27 mL/min, 95 % CI 0.08-0.46, I² = 95 %, p < 0.00001).

CONCLUSION

PBM appears to minimize radiation-induced hyposalivation.

Impact of radiotherapy on mandibular bone: A retrospective study of digital panoramic radiographs

Purpose

The purpose of this study was to investigate the impact of radiotherapy on mandibular bone tissue in head and neck cancer patients through an analysis of pixel intensity and fractal dimension values on digital panoramic radiographs.

Materials and Methods

Thirty patients with radiographic records from before and after 3-dimensional (3D) conformational radiotherapy were selected. A single examiner carried out digital analyses of pixel intensity values and fractal dimensions, with the areas of interest unilaterally located in the right angle medullary region of the mandible below the mandibular canal and posterior to the molar region.

Results

Statistically significant decreases were observed in the mean pixel intensity (P=0.0368) and fractal dimension (P=0.0495) values after radiotherapy.

Conclusion

The results suggest that 3D conformational radiotherapy for head and neck cancer negatively affected the trabecular microarchitecture and mandibular bone mass.