METHODS: We scrutinized the routine radiological exposure parameters during 58 clinical neuro-interventional procedures such as, exposure direction, magnification, frame rate, and distance between image receptor to patient's body and evaluate their effects on patient's dose using an anthropomorphic phantom. Radiation dose received by the occipital region, ears and eyes of the phantom were measured using MOSkin detectors.
RESULTS: DSA imaging technique is a major contributor to patient's dose (80.9%) even though they are used sparingly (5.3% of total frame number). The occipital region of the brain received high dose largely from the frontal tube constantly placed under couch (73.7% of the total KAP). When rotating the frontal tube away from under the couch, the radiation dose to the occipital reduced by 40%. The use of magnification modes could increase radiation dose by 94%. Changing the image receptor to the phantom surface distance from 10 to 40cm doubled the radiation dose received by the patient's skin at the occipital region.
CONCLUSION: Our findings provided important insights into the contribution of selected fluoroscopic exposure parameters and their impact on patient's dose during neuro-interventional radiology procedures. This study showed that the DSA imaging technique contributed to the highest patient's dose and judicial use of exposure parameters might assist interventional radiologists in effective skin and eye lens dose reduction for patients undergoing neuro-interventional procedures.
PATIENTS AND METHODS: Twenty patients presenting with haemorrhagic radiation proctitis and treated with formalin dab were prospectively analysed.
RESULTS: Twelve patients ceased to bleed following one session of formnalin dab. Six patients needed more than one session to effect haemostasis. Two of three patients with torrential bleeding failed to respond to formalin dab and required surgical excision of the rectum.
CONCLUSION: Formalin dab is a simple, effective and safe treatment modality in the management of chronic haemorrhagic radiation proctitis, and hence should be considered as the initial treatment modality for such a condition.
MATERIALS/METHODS: Multivariable models developed to predict atomised and generalised urinary symptoms, both acute and late, were considered for validation using a dataset representing 754 participants from the TROG 03.04-RADAR trial. Endpoints and features were harmonised to match the predictive models. The overall performance, calibration and discrimination were assessed.
RESULTS: 14 models from four publications were validated. The discrimination of the predictive models in an independent external validation cohort, measured using the area under the receiver operating characteristic (ROC) curve, ranged from 0.473 to 0.695, generally lower than in internal validation. 4 models had ROC >0.6. Shrinkage was required for all predictive models' coefficients ranging from -0.309 (prediction probability was inverse to observed proportion) to 0.823. Predictive models which include baseline symptoms as a feature produced the highest discrimination. Two models produced a predicted probability of 0 and 1 for all patients.
CONCLUSIONS: Predictive models vary in performance and transferability illustrating the need for improvements in model development and reporting. Several models showed reasonable potential but efforts should be increased to improve performance. Baseline symptoms should always be considered as potential features for predictive models.
Objective: In this study, bystander effects in MCF-7 breast cancer cells and hFOB 1.19 normal osteoblast cells irradiated with gamma emitting HDR Brachytherapy Ir-192 source were investigated.
Material and Methods: In this in-vitro study, bystander effect stimulation was conducted using medium transfer technique of irradiated cells to the non-irradiated bystander cells. Cell viability, reactive oxygen species (ROS) generation and colony forming assay was employed to evaluate the effect.
Results: Results indicate that the exposure to the medium irradiated MCF-7 induced significant bystander killing and decreased the survival fraction of bystander MCF-7 and hFOB from 1.19 to 81.70 % and 65.44 %, respectively. A significant decrease in survival fraction was observed for hFOB 1.19 bystander cells (p < 0.05). We found that the rate of hFOB 1.19 cell growth significantly decreases to 85.5% when added with media from irradiated cells. The ROS levels of bystander cells for both cell lines were observed to have an increase even after 4 h of treatment. Our results suggest the presence of bystander effects in unirradiated cells exposed to the irradiated medium.
Conclusion: These data provide evidence that irradiated MCF-7 breast cancer cells can induce bystander death in unirradiated MCF-7 and hFOB 1.19 bystander cells. Increase in cell death could also be mediated by the ROS generation during the irradiation with HDR brachytherapy.
PATIENTS AND METHODS: Forty patients diagnosed with head and neck cancer requiring radiation to the oropharyngeal mucosal area were divided in to two groups to receive either radiation alone or radiation plus topical application of pure natural honey. Patients were treated using a 6-MV linear accelerator at a dose rate of 2 Gy per day five times a week up to a dose of 60-70 Gy. In the study arm, patients were advised to take 20 ml of pure honey 15 min before, 15 min after and 6 h post-radiation therapy. Patients were evaluated every week for the development of radiation mucositis using the Radiation Therapy Oncology Group (RTOG) grading system.
MAIN RESULTS: There was significant reduction in the symptomatic grade 3/4 mucositis among honey-treated patients compared to controls; i.e. 20% versus 75% ( p 0.00058). The compliance of honey-treated group of patients was better than controls. Fifty-five percent of patients treated with topical honey showed no change or a positive gain in body weight compared to 25% in the control arm ( p 0.053), the majority of whom lost weight.
CONCLUSIONS: Topical application of natural honey is a simple and cost-effective treatment in radiation mucositis, which warrants further multi-centre randomised trials to validate our finding.
METHODS: Head and neck cancer patients were recruited from July 2016 till March 2017 at National Cancer Institute, Ministry of Health, Malaysia. All study participants continued their standard oncology surveillance. Treatment group participants additionally received Chinese herbal treatment. The assessments included unstimulated salivary flow rate (USFR), stimulated salivary flow rate (SSFR), and QoL questionnaire.
RESULTS: Of 42 recruited participants, 28 were in the treatment group and 14 were in the control group. Participants were mainly Chinese (71.4%), stage III cancer (40.5%), and had nasopharynx cancer (76.2%). The commonly used single herbs were Wu Mei, San Qi, and Tian Hua Fen. Sha Shen Mai Dong Tang, Liu Wei Di Huang Wan, and Gan Lu Yin were the frequently prescribed herbal formulas. The baseline characteristics, USFR, SSFR, and QoL between control and treatment groups were comparable (p > 0.05). USFR between control and treatment groups were similar throughout the 6-month study period. SSFR for the treatment group significantly improved from 0.15 ± 0.28 ml/min (baseline) to 0.32 ± 0.22 ml/min (p = 0.04; at the 3rd month) and subsequently achieved 0.46 ± 0.23 ml/min (p = 0.001; at the 6th month). The treatment group had better QoL in terms of speech (p = 0.005), eating (p = 0.02), and head and neck pain (p = 0.04) at the 6th month.
CONCLUSION: Herbal treatment may improve xerostomia and QoL in post-radiotherapy head and cancer patients.
MATERIALS AND METHODS: Original research studies associating genetic features and normal tissue complications following radiotherapy were identified from PubMed. The use of dosimetric data was determined by mining the statement of prescription dose, dose fractionation, target volume selection or arrangement and dose distribution. The consideration of the dosimetric data as covariates was based on the statement mentioned in the statistical analysis section. The significance of these covariates was extracted from the results section. Descriptive analyses were performed to determine their completeness and inclusion as covariates.
RESULTS: A total of 174 studies were found to satisfy the inclusion criteria. Studies published ≥2010 showed increased use of dose distribution information (p = 0.07). 33% of studies did not include any dose features in the analysis of gene-toxicity associations. Only 29% included dose distribution features as covariates and reported the results. 59% of studies which included dose distribution features found significant associations to toxicity.
CONCLUSION: A large proportion of studies on the correlation of genetic markers with radiotherapy-related side effects considered no dosimetric parameters. Significance of dose distribution features was found in more than half of the studies including these features, emphasizing their importance. Completeness of radiation-specific clinical data may have increased in recent years which may improve gene-toxicity association studies.