Delineation of the "Oropharyngeal Mucosa" and Limiting its Dose in Head and Neck Cancer Patients Spares the Oropharynx Without Compromising Target Coverage.

OBJECTIVES: Radiation-induced oropharyngeal injury is a dose-limiting toxicity in head and neck cancer patients. Delineation of the "oropharyngeal mucosa" and limiting its dose to spare the oropharynx was investigated. METHODS: In this retrospective study, computed tomography imaging from eight patients with previously untreated head and neck cancer was employed. An adaptive contouring brush within the planning software Monaco was used to create an air cavity within the oropharynx, and then the air cavity was expanded uniformly 2 mm to create the "oropharyngeal mucosa". Three plans were independently generated for each patient: Plan1: dose constraint was applied for the oropharynx; Plan2: dose constraints were applied for the oropharynx and the "oropharyngeal mucosa"; Plan3: dose constraint was applied for the "oropharyngeal mucosa". T-tests were used to compare the dosimetry variables. RESULTS: All plans had adequate target coverage and there were no statistical differences among plans. The mean dose, D30%, D45%, D50%, D85%, D90%, D95%, D100%, V25 Gy, V30 Gy, V35 Gy, V40 Gy, and V45 Gy of the oropharynx and "oropharyngeal mucosa" in Plan1 were significantly higher than those in Plan2 and Plan3. There were no significant differences between Plan2 and Plan3. There were no significant differences in the dosimetric parameters of any other organs at risk. CONCLUSION: Delineation of the "oropharyngeal mucosa" and limiting its dose should be an easy and effective method to spare the oropharynx.

Radiation-induced oropharyngeal injury is dose-limiting toxicity in head and neck cancer patients. Delineation of "oropharyngeal mucosa" and limiting its dose should be an easy and effective method to spare the oropharynx.

Blue light-emitting diode in healthy vaginal mucosa-a new therapeutic possibility.

A healthy female genital mucosa has an ecosystem that remains in balance through interactions between endogenous and exogenous factors. The light-emitting diode (LED) is a device that emits light at different wavelengths, with varying color and effects. Blue light in humans is most commonly used for antimicrobial purposes and has been already applied to treat facial acne and gastric bacteria. Although blue LED therapy in humans has been reported, its properties against vaginal infections have not yet been investigated. This study aims to test the safety and effects of 401 ± 5 nm blue LED on healthy vaginal mucosa. Phase I clinical trial involving 10 women between 18 and 45 years old with healthy vaginal mucosa. The participants were illuminated by 401 ± 5 nm blue LED for 30 min and anamnesis, oncotic cytology, and pH measurement were made again after 21/28 days of treatment. In the re-evaluation, adverse effects were investigated. The mean age was 27 ± 5.4 years and one of the women was excluded due to interruption of use of oral contraceptives. Oncotic cytology done before and after therapy showed that the composition of the microflora remained normal in all participants. Vaginal pH remained unchanged in eight of the women and had a reduction in one woman (5.0-4.0). No adverse effects were observed during or after illumination. 401 ± 5 nm blue LED did not generate any adverse effects or pathogenic changes in the microflora and vaginal pH. The effects of 401 ± 5 nm blue LED still need to be tested in vulvovaginal pathogens. Trial registration number: NCT03075046.

Effectiveness of Low-Level Laser Therapy with a 915 Nm Wavelength Diode Laser on the Healing of Intraoral Mucosal Wound: An Animal Study and a Double-Blind Randomized Clinical Trial.

Background and objectives: Diode laser has been the most popular low-level laser therapy (LLLT) technique in dentistry due to its good tissue penetration, lower financial costs, small size for portable application, and convenience to use. A series of recent studies with 940 nm or 980 nm lasers demonstrated that LLLT showed positive effects after third molar extraction or periodontal flap surgery. However, the effects of LLLT on intraoral mucosal wound healing after surgical incision have not yet been determined in human clinical study. Materials and Methods: The present study was performed to determine the efficacy and safety of 915 nm wavelength low-level laser therapy (LLLT) in mucosal wound healing. A total of 108 Sprague-Dawley rats were used. They were divided into three groups: Abrasive wound group, immediate LLLT once group, and daily LLLT group. As a clinical study, a total of 16 patients with split-mouth design subjected to bilateral mandibular third molar extraction were allocated into the LLLT group and placebo group. The process of LLLT was performed on postoperative days 0, 1, and 7, and parameters related to wound healing were analyzed on days 1, 7, and 14. Results: Repeated laser irradiation promoted mucosal wound healing of the rats. In the clinical study, although there were no significant statistical differences between the LLLT and placebo groups in all inflammatory parameters, the early stage mucosal healing tendency of wound dehiscence was higher in the LLLT group than in the placebo group clinically on postoperative day 1. Conclusions: The present results showed that 915 nm LLLT could be applied safely as an auxiliary therapy for mucosal wound healing.

Comparative study on the incision healing of the palatal mucosa by using Er:YAG laser or traditional scalpel in the SD rats.

The aim of this study was to compare the histology of wound healing following incisions with the scalpel or the Er:YAG laser in the palatal mucosa of SD rats. Two types of wounds were performed with the stainless steel scalpel or the Er:YAG laser in the palatal mucosa of SD rats, while the adjacent untreated palatal mucosa was chosen as control. Rats were sacrificed on day 1, day 3, day 7, and day 30 post-surgery. Biopsy samples from each wound were examined and the expression of IL-1ß and TGF-ß1 was determined by enzyme-linked immunosorbent assay (ELISA). The early postoperative incision of the scalpel group had obvious bleeding and swelling, while the laser wound mainly covered the surface of white pseudomembrane. The infiltration of neutrophils and lymphocytes in the stroma of the scalpel incision was more than that of the laser group. Compared to the laser group, 1 and 3 days after operation, the TGF-ß1 content of the scalpel group were significantly increased (P = 0.032 and 0.019). Seven days after operation, the TGF-ß1 content of two groups was decreased. TGF-ß1 expression of control group was obviously increased (P > 0.05); 1, 3, and 7 days after operation, the traditional scalpel amount of IL-1ß expression was significantly higher than that of control group (P = 0.000, 0.000, and 0.001). Postoperative day 1, IL-1ß expression of laser group and control group had no significant difference (P = 0.572). Three days after operation, IL-1ß expression of laser incision was increased and was significantly higher than that in control group (P = 0.032), however lower than the scalpel group (P = 0.03). Seven days after operation, the IL-1ß expression of two groups had no significant difference (P = 0.333); however, the IL-1ß expression of two groups were significantly higher than that of the control group (P = 0.02 and 0.001). Compared to the traditional scalpel, the incision of Er:YAG laser has smaller inflammation reaction, more pseudomembrane coverage, and minimal damage of the mucoperiosteal tissue.

Early effects of irradiation on laryngeal mucosa in a gastroesophageal reflux model: an experimental study.

OBJECTIVE: The aim of this study was to evaluate the early histopathological changes of gastroesophageal reflux and irradiation on laryngeal mucosa in rats. STUDY DESIGN: Animal study. SETTING: Experimental animal laboratory, tertiary referral center. SUBJECT AND METHOD: Twenty-four adult female Wistar Albino rats were grouped as: control (n = 6), reflux and irradiation (n = 10), and irradiation (n = 8). Rats were operated to create a reflux model 30 days before irradiation. Ionizing radiation was administered in a single fraction of a 20 Gy to the larynx. Laryngeal tissue samples were taken at the 4th day of irradiation and all specimens underwent histopathological examination. RESULTS: Edema and vascular dilation in lamina propria were higher in the reflux and irradiation, and irradiation groups than control group. Inflammation was higher in the reflux and irradiation group than the control group. Inflammation in squamous epithelium was higher in the reflux and irradiation and irradiation groups compared to the control group. Inflammation in the squamous epithelium of the irradiation group was higher than the reflux and irradiation group. In the respiratory tract epithelium, inflammation was higher in the reflux and irradiation group; additionally, a significant loss of cilia was present in the reflux and irradiation and irradiation groups while pseudostratification was higher in the reflux and irradiation group. CONCLUSION: Ionizing radiation-induced inflammation may increase on previously inflammated area due to gastroesophageal reflux. Therefore, it may be helpful to investigate and treat the reflux in laryngeal cancer patients that will receive ionizing radiation.

Asian expert recommendation on management of skin and mucosal effects of radiation, with or without the addition of cetuximab or chemotherapy, in treatment of head and neck squamous cell carcinoma.

With increasing numbers of patients with unresectable locoregionally advanced (LA) head and neck squamous cell carcinoma (HNSCC) receiving cetuximab/radiotherapy (RT), several guidelines on the early detection and management of skin-related toxicities have been developed. Considering the existing management guidelines for these treatment-induced conditions, clinical applicability and standardization of grading methods has remained a cause of concern globally, particularly in Asian countries. In this study, we attempted to collate the literature and clinical experience across Asian countries to compile a practical and implementable set of recommendations for Asian oncologists to manage skin- and mucosa-related toxicities arising from different types of radiation, with or without the addition of cetuximab or chemotherapy. In December 2013, an international panel of experts in the field of head and neck cancer management assembled for an Asia-Pacific head and neck cancer expert panel meeting in China. The compilation of discussion outcomes of this meeting and literature data ultimately led to the development of a set of recommendations for physicians with regards to the approach and management of dermatological conditions arising from RT, chemotherapy/RT and cetuximab/RT, and similarly for the approach and management of mucositis resulting from RT, with or without the addition of chemotherapy or cetuximab. These recommendations helped to adapt guidelines published in the literature or text books into bedside practice, and may also serve as a starting point for developing individual institutional side-effect management protocols with adequate training and education.

Microscopic and ultrastructural modifications of postmenopausal atrophic vaginal mucosa after fractional carbon dioxide laser treatment.

Vaginal atrophy occurring during menopause is closely related to the dramatic decrease in ovarian estrogens due to the loss of follicular activity. Particularly, significant changes occur in the structure of the vaginal mucosa, with consequent impairment of many physiological functions. In this study, carried out on bioptic vaginal mucosa samples from postmenopausal, nonestrogenized women, we present microscopic and ultrastructural modifications of vaginal mucosa following fractional carbon dioxide (CO2) laser treatment. We observed the restoration of the vaginal thick squamous stratified epithelium with a significant storage of glycogen in the epithelial cells and a high degree of glycogen-rich shedding cells at the epithelial surface. Moreover, in the connective tissue constituting the lamina propria, active fibroblasts synthesized new components of the extracellular matrix including collagen and ground substance (extrafibrillar matrix) molecules. Differently from atrophic mucosa, newly-formed papillae of connective tissue indented in the epithelium and typical blood capillaries penetrating inside the papillae, were also observed. Our morphological findings support the effectiveness of fractional CO2 laser application for the restoration of vaginal mucosa structure and related physiological trophism. These findings clearly coupled with striking clinical relief from symptoms suffered by the patients before treatment.

Severe retinopathy following radiation therapy with a moderate dose for orbital mucosa-associated lymphoid tissue lymphoma.

Mucosa-associated lymphoid tissue (MALT) lymphoma is a radiosensitive malignancy. We report on a case of severe retinopathy following radiation therapy with a moderate dose for orbital MALT lymphoma. A 69-year-old woman with orbital MALT lymphoma received definitive radiation therapy with a total dose of 36 Gy in 18 fractions. The patient showed complete response but had severe retinopathy along with marked deterioration in visual acuity at 2 years after irradiation. Although the patient underwent treatments for retinopathy, including laser photocoagulation and steroid injection, improvement of the visual acuity was modest. This case developed severe radiation-induced retinopathy after radiation therapy with the moderate dose of 36 Gy that is considered to be usually safe.

[Study on efficacy of liujunzi decoction combined with zuojin pills in treating acute radioactive duodenitis and their mechanism].

OBJECTIVE: To evaluate the therapeutic effect of Liujunzi decoction combined with Zuojin pills in treating the radioactive duodenitis and their mechanism, and compare with clinical routine acid suppressants combined with mucous membrane protective preparations to study the mechanism of their efficacy. METHOD: According to the study of Williams J P and characteristics of duodenitis, and by reference to the radiation enteritis modeling standard, we took the lead in establishing the mouse radioactive duodenal injury model. The model mice were randomly divided into the control group (n = 26), traditional Chinese medicine (TCM) group (n = 16) and the western medicine (oral administration with famotidine 0.5 mL + almagate suspension 0.3 mL per mouse, once a day) group (n = 16). After the standard administrating, such objective indexes as general condition, weight, changes in health score, pathology and expression of inflammatory factors were observed to evaluate the efficacy. RESULT: The radioactive duodenitis model of mice was successfully established with 12 Gy. Mice in the control group suffered from weight loss, anorexia, low fluid intake, loose stools, and occasionally mucous bloody stool, poor spirit, dim fur, lack of exercise and arch back. Mice in drug intervention groups were generally better than those in the pure irradiation group. The IL-6, IL-1beta, TNF-alpha mRNA expressions in spleen and mesenteric lymph node tissues in TCM and western medicine groups showed a declining trend compared with the control group. Their concentrations in peripheral blood serum also slightly changed. The TCM group revealed notable advantage in reducing inflammatory factors. The microscopic observation showed that a better mucosa repair in intervention groups than the pure irradiation group. The improved Chiu's scoring method showed a statistical significance in the difference between TCM and western medicine groups (P < 0.05). CONCLUSION: Liujunzi decoction combined with Zuojin pills could treat acute radiation enteritis, regulate organic immunity, and inhibit acute injury, promote local tissue repair, with the potential to resist such adverse effects as radiation intestinal fibrosis. The regulation of inflammatory factor release is one of efficacy generation mechanisms.

Nutritional supplementation with L-arginine prevents pelvic radiation-induced changes in morphology, density, and regulating factors of blood vessels in the wall of rat bladder.

PURPOSE: To determine whether L-arginine has protective effects against radiation-induced alterations in the morphology and regulatory factors of vesical blood vessels in rats. METHODS: Male rats aged 3-4 months were divided into groups of 10 animals each: (a) controls, consisting of non-treated animals; (b) radiated-only rats; and (c) radiated rats receiving L-arginine supplementation. Radiation was in one session of 10 Gy and was aimed at the pelvic-abdominal region. L-arginine was administered once a day (0.65 g/kg body weight), starting 7 days before radiation and continuing until killing on the 16th day after radiation. The density, relative area, and wall thickness of blood vessels were measured in the vesical lamina propria using histological methods, and the expression of vascular endothelial growth factor (VEGF) and fibroblast growth factors (FGF) in the bladder wall was assessed by RT-PCR. RESULTS: Compared with controls, radiation alone decreased the density and relative area of blood vessels by 32 % (p < 0.01) and 25 % (p < 0.05), respectively, and reduced the arterial wall thickness by 42 % (p < 0.004). VEGF and FGF mRNA levels after radiation were diminished by 67 % (p < 0.002) and 56 % (p < 0.04), respectively. The radiated animals supplemented with L-arginine were not significantly different from controls. CONCLUSIONS: Pelvic radiation leads to significant vesical modifications, as in the morphology of blood vessels and in VEGF and FGF expression. All these changes, however, were prevented by L-arginine treatment. These results emphasize, therefore, the potential use of this amino acid as a radioprotective drug.

Personalized Radiation Attenuating Materials for Gastrointestinal Mucosal Protection.

Cancer patients undergoing therapeutic radiation routinely develop injury of the adjacent gastrointestinal (GI) tract mucosa due to treatment. To reduce radiation dose to critical GI structures including the rectum and oral mucosa, 3D-printed GI radioprotective devices composed of high-Z materials are generated from patient CT scans. In a radiation proctitis rat model, a significant reduction in crypt injury is demonstrated with the device compared to without (p < 0.0087). Optimal device placement for radiation attenuation is further confirmed in a swine model. Dosimetric modeling in oral cavity cancer patients demonstrates a 30% radiation dose reduction to the normal buccal mucosa and a 15.2% dose reduction in the rectum for prostate cancer patients with the radioprotectant material in place compared to without. Finally, it is found that the rectal radioprotectant device is more cost-effective compared to a hydrogel rectal spacer. Taken together, these data suggest that personalized radioprotectant devices may be used to reduce GI tissue injury in cancer patients undergoing therapeutic radiation.

Role of reflux in tracheoesophageal fistula problems after laryngectomy.

OBJECTIVES: The purpose of this 2-year prospective nonrandomized study was to investigate the relationship between pathological supraesophageal reflux and the occurrence of speech fistula complications, especially severe fistula enlargement, in patients who underwent total laryngectomy and prosthetic voice restoration. METHODS: We objectively assessed the presence of reflux disease using 24-hour dual-probe pH monitoring in 60 laryngectomized patients, correlated the incidence of tracheoesophageal fistula complications with the severity of reflux, and assessed the risk of problems by determining the absolute number of reflux events at the level of the speech fistula, the reflux area index score, and the DeMeester score. RESULTS: All patients with fistula enlargement showed highly pathological results in the diagnostic tests for reflux disease. Depending on reflux severity, the relative risk of developing fistula complications was up to 10 times higher for these patients. CONCLUSIONS: We found a significant correlation between the occurrence of tracheoesophageal fistula complications and the severity of supraesophageal reflux. Potential chronic irritation of the esophageal and tracheal mucosa can possibly contribute to the development of these problems. If the presence of reflux disease has been confirmed by 24-hour dual-probe pH monitoring, patients with fistula complications should be treated with proton pump inhibitors.

Dose perturbation due to the polysulfone cap surrounding a Fletcher-Williamson colpostat.

We conducted a metrological evaluation of the dosimetric impact due to the polysulfone cap used with the Fletcher-Williamson (FW) colpostat for 192Ir high-dose rate and pulsed-dose rate intracavitary brachytherapy using Monte Carlo simulations. Polysulfone caps with diameter of 30 mm, 25 mm, 20 mm, and 16 mm (mini-ovoid) were simulated and the absorbed dose rate in the surrounding water was calculated and compared to the dose rate for a bare 192Ir source in water. The dose perturbation depended on the cap diameter, distance away from the cap surface, and angular position around the cap. The largest dose rate reductions were found to be in the direction of the tumor bed where the cap is thickest. The range of perturbation over all depths and cap diameters was +2.8% (dose enhancement) to -6.8% (dose reduction). The FW colpostat cap's material composition should be modified to reduce this dosimetric effect or brachytherapy treatment planning dose algorithms should be improved to account for this perturbation.

BMP Antagonists Secreted by Mesenchymal Stromal Cells Improve Colonic Organoid Formation: Application for the Treatment of Radiation-induced Injury.

Radiation therapy is crucial in the therapeutic arsenal to cure cancers; however, non-neoplastic tissues around an abdominopelvic tumor can be damaged by ionizing radiation. In particular, the radio-induced death of highly proliferative stem/progenitor cells of the colonic mucosa could induce severe ulcers. The importance of sequelae for patients with gastrointestinal complications after radiotherapy and the absence of satisfactory management has opened the field to the testing of innovative treatments. The aim of this study was to use adult epithelial cells from the colon, to reduce colonic injuries in an animal model reproducing radiation damage observed in patients. We demonstrated that transplanted in vitro-amplified epithelial cells from colonic organoids (ECO) of C57/Bl6 mice expressing green fluorescent protein implant, proliferate, and differentiate in irradiated mucosa and reduce ulcer size. To improve the therapeutic benefit of ECO-based treatment with clinical translatability, we performed co-injection of ECO with mesenchymal stromal cells (MSCs), cells involved in niche function and widely used in clinical trials. We observed in vivo an improvement of the therapeutic benefit and in vitro analysis highlighted that co-culture of MSCs with ECO increases the number, proliferation, and size of colonic organoids. We also demonstrated, using gene expression analysis and siRNA inhibition, the involvement of bone morphogenetic protein antagonists in MSC-induced organoid formation. This study provides evidence of the potential of ECO to limit late radiation effects on the colon and opens perspectives on combined strategies to improve their amplification abilities and therapeutic effects.

Assessment of a sheep animal model to optimise photodynamic therapy in the oesophagus.

BACKGROUND AND OBJECTIVES: Precursor lesions of oesophagus adenocarcinoma constitute a clinical dilemma. Photodynamic therapy (PDT) is an effective treatment for this indication, but it is difficult to optimise without an appropriate animal model. For this reason, we assessed the sheep model for PDT in the oesophagus with the photosensitiser meta-(tetra-hydroxyphenyl) chlorin (mTHPC). MATERIALS AND METHODS: Twelve sheep underwent intravenous mTHPC injection, blood sampling and fluorescence measurements. mTHPC's pharmacokinetics was measured in vivo and in plasma by fluorescence spectroscopy. Biopsies of sheep oesophagus were compared to corresponding human tissue, and the mTHPC's biodistribution was studied under fluorescence microscopy. Finally, the sheep oesophageal mucosa was irradiated, 4 days after mTHPC's injection. RESULTS: Histologically, the sheep and human oesophagus were closely comparable, with the exception of additional fatty tissue in the sheep oesophagus. mTHPC's pharmacokinetics in sheep and human plasmas were similar, with a maximum of concentration in the sheep 10 hours after i.v. injection. mTHPC's pharmacokinetics in vivo reached its maximum after 30-50 hours, then decreased to background levels, as in humans under similar conditions. Two days after injection, mTHPC was mainly distributed in the lamina propria, followed by a penetration into the epithelium. The sheep and human tissue sensitivity to mTHPC PDT was similar. CONCLUSION: In conclusion, this model showed many similarities with humans as to mTHPC's plasma and tissue pharmacokinetics, and for tissue PDT response, making it suitable to optimise oesophagus PDT.

IMRT-based treatment of unknown primary malignancy of the head and neck: Outcomes and improved toxicity with decreased mucosal dose and larynx sparing.

BACKGROUND: Radiation therapy for squamous cell cancer of the head and neck with unknown primary (head and neck CUP) has been associated with significant levels of swallowing toxicity. We examined the effect of changes in mucosal dose on development of laryngeal strictures and percutaneous endoscopic gastrostomy (PEG) dependence. METHODS: Retrospective analysis of 58 patients with head and neck CUP treated with intensity-modulated radiation therapy (IMRT) at the Dana Farber Cancer Institute from August 2004 through July 2013. RESULTS: There were no significant differences between any recurrences for groups treated to 56 versus ≥60 Gy to the mucosal surfaces. However, mucosal dose and chemotherapy type were associated with stricture on multivariable analysis; median PEG dependence was decreased for patients treated to 56 Gy. A larynx-sparing approach was associated with improved outcomes for strictures and PEG use. CONCLUSION: In this single institution study, a 56 Gy IMRT-based mucosal dose demonstrated significant improvements in swallowing toxicity. Additional benefit was seen with larynx-sparing IMRT.

[Brachytherapy at the Institut Gustave-Roussy: personalized vaginal mould applicator: technical modification and improvement]. / Curiethérapie à l'institut Gustave-Roussy: applicateur moulé vaginal personnalisé: modification et amélioration techniques.

Brachytherapy plays an important role in the treatment of patients with gynaecological cancers. At the Institut Gustave-Roussy, the technique of vaginal mould applicator has been used for decades. This technique allows a personalized tailored irradiation, integrating tumour shape, size and extension and vaginal anatomy. Vaginal expansion reduces the dose to the vaginal mucosa and to the organs at risk. We report a modification of the material used for vaginal mould manufacture. The advantages of the new material are a lighter weight, and transparency allowing a better accuracy in the placement of catheters for radioactive sources. This material is applicable for low dose-rate, pulse dose-rate and high dose-rate brachytherapy. Since 2001, more than 700 vaginal moulds have been manufactured with this new approach without any intolerance.

Postoperative adjuvant radiation therapy in the treatment of primary head and neck mucosal melanomas.

BACKGROUND/AIMS: The role of postoperative radiotherapy (PORT) in head and neck mucosal melanomas (HNMM) is not yet clearly defined. The aim of this study is to report the 21-year experience of the Brazilian National Cancer Institute in such treatment. METHODS: From January 1983 to December 2003, 31 patients with confirmed histological diagnosis of HNMM underwent treatment at the Brazilian National Cancer Institute. Of these, 20 received radical treatment with surgery alone (8 patients--group 1) or surgery and PORT (12 patients--group 2). RESULTS: Local control and the median time to local failure at 5 years were 75% and 14 months for group 1 and 83.5% and 40 months for group 2 (p = 0.06). The overall survival rates at 3 years were 37.5% for group 1 and 58% for group 2. At 5 years the survival rates were 25% for both groups (p = NS). When PORT was initiated within 60 days after surgery, there was a trend towards improvement in overall survival (p = 0.08). After univariate analysis, distant metastasis, location of primary disease and tobacco smoking were important prognostic factors. CONCLUSION: Early (<60 days) PORT for HNMM provides better local control with a longer disease-free survival.

Dosimetry calculations for internal electron sources using a Korean reference adult stylised phantom.

Absorbed fractions (AFs) and specific absorbed fractions (SAFs) for internally deposited electron were calculated using a Korean reference adult stylised phantom, where a total of 15 internal organ volumes and external body dimension were designed to match average Korean adult male. The walls of oesophagus, stomach, colon and urinary bladder were additionally divided into the mucosal layer and residual wall to accommodate dose calculation for weakly penetrating electron. The mucosal wall thicknesses were determined by the data reported in the International Commission on Radiological Protection Publication 89 and other literature resources and by direct measurements. The Monte Carlo transport code MCNPX (version 2.5.0) was employed to calculate the electron energy deposited. The SAFs and AFs for monoenergetic electrons with the energies ranging from 10 keV to 2 MeV were calculated. The results were compared with those of the revised Oak Ridge National Laboratory phantoms and showed considerable differences up to 150% in SAFs, whereas no substantial differences were observed in the AFs.

[Assessment of mucosal injury in stage T1-T2NOMO bladder cancer after radiation or intravesical chemotherapy].

The report reviews the experience gained with radio- and chemotherapy-related injuries suffered by bladder cancer patients. It corroborates the opinion of most European specialists that indications for radical cystectomy be extended with due considerations of up-to-date potential in anesthesiology, extensive care and pharmacology. Possible untoward side effects of radiation and intravesical chemotherapy as well as means of solution of the problem are discussed. It is urgent considering the constantly growing number of such patients, their age and associated somatic problems.