International Journal of Radiation Research
Year:2017 | Volume:15 | Issue:1|Papers Count:15

Background: Boron neutron capture therapy (BNCT) is a radiotherapy that combines biological targe ng and high linear energy transfer. A poten al therapeu c approach for non-small cell lung cancer (NSCLC) is considered. However, dose in lung tumor is not homogeneous, and it will reduce the effect of BNCT treatment. In order to improve the dose distribu on of BNCT, the mul-field irradia on strategy and its effects need to be explored. Materials and Methods: Common NSCLC model was defined in Chinese hybrid reference phantom and the boron concentra on in skin and tumor varied from 6 to 18 ppm and from 30 to 65 ppm, respec vely. Monte Carlo method for dose distribu on calcula on was used. Accelerator-based neutron source called “ Neuboron source” was used and mul-field source irradia on plans were designed to op mize the dose distribu on. Results: Under onefield irradia on, it was not feasible to perform BNCT, because the skin dose is unlikely to meet its dose limit. Under two-and three-field irradia on, the uniformity of tumor dose was improved and the maximum dose to organs at risk (OARs) decreased. If boron concentra on in skin was between 6-18 ppm, BNCT was feasible with the boron concentra on in tumor reaching about 57-60 ppm for two-field irradia on and 41-45 ppm for three-field irradia on, respec vely. Conclusion: The mul-field irradia on plan could improve the dose distribu on and the feasibility of BNCT for NSCLC. Theore cal distribu ons of Boron-10 were obtained to meet the treatable requirement of BNCT, which could provide a reference for NSCLC using BNCT in future mul ple-field irradia on.

Background: Normal tissue toxicity continues to remain as a major challenge for radiation oncologists for delivering the total dose to the tumour cells in cancer patients. Cellular, molecular and plasma based early biomarkers to predict the overreactions and non-overreactions of normal tissue toxicity before the initiation of radiotherapy can be valuable for personalised treatment. The aim of the current study was to analyse the interrelationship between polymorphisms in Glutathione S-Transferases (GSTs) and Transforming Growth Factor-β 1 (TGF-ß 1), the plasma level/activity of these proteins with the development of chemo-radiotherapy induced oral mucositis and skin reaction in head and neck cancer (HNC) patients. Materials and Methods: We analysed polymorphisms in TGF-β 1 and GST by restriction digestion of the PCR amplified products and we also assessed circulating TGF-β 1 levels and GST activity by Enzyme Linked Immunosorbent Assay (ELISA). Results: The results indicate that pre-radiotherapy plasma TGF-β 1 levels and total GST activity has no correlation with radiation induced normal tissue skin reaction and oral mucositis in HNC patients. Conclusion: The selected polymorphisms in TGF-β 1 and GST had no influence on TGF-β 1 levels and total GST activity. Plasma TGF-β 1 and GST activity was not affected by the presence of selected polymorphisms and lacks significance in predicting skin reaction and oral mucositis prior to chemo-radiotherapy.

Background: Fa gue is a common side effect in cancer pa ents undergoing radia on therapy (RT). Radia on-induced fa gue affects the quality of life, but there is no defini ve treatment op on. In this study, the weight-loaded forced swim test was performed to assess the effect of coenzyme Q10 (CoQ10) on radia on-induced fa gue. Materials and Methods: A total of 60 rats were divided randomly and equally into four groups: No swim, No RT, RT + placebo, or RT + CoQ10. The No swim, No RT, and RT + placebo groups received 1 mL of soybean oil daily for 14 days. The RT + CoQ10 group received 100 mg/kg of CoQ10 in soybean oil at the same  mes. Both RT groups were irradiated with 10 Gy on the 14th day of treatment. The swim test with sinkers weighing 10% of body weight was performed 24 h later in all animals except the No swim group. Results: The level of blood urea nitrogen (BUN) was significantly lower in the No swim than the other groups. The BUN level of the No RT group was significantly decreased compared with the RT + placebo group, but it did not differ from the RT + CoQ10 group. Swimming  mes to complete exhaus on were significantly longer in the No RT and RT + CoQ10 groups compared to the RT + placebo group (99. 4, 105. 9, and 75. 7 s, respec vely) (P<0. 001). Conclusion: Supplementa on with CoQ10 can prevent the decrease in endurance capacity caused by radia on.

Background: This study evaluated the rela on between telomere length in lymph node (LN) and prognosis of esophageal squamous cell carcinoma (ESCC). Materials and Methods: LNs collected from 50 pa ents were assessed by pathological examina on and quan ta ve reverse transcrip on polymerase chain reac on (qRT-PCR), which was used for detec ng telomere length. The rela on between clinical factors and the number of lymph node metastasis (LNM) iden fied were analyzed by the χ 2 test. The comparison of the pa. ern of LNM iden fied by pathological examina on and detec on of telomere length was assessed by Wilcoxon signed-rank test. Overall survival was assessed using the Kaplan-Meier method, and Cox propor onal hazard regression analysis was used to evaluate the rela onship between survival and the number of LNM. Results: The best threshold values, which could define the posi ve metastasis by detec ng the telomere length, were 1. 50, using the cri cal value method of sta s c. Length of tumor, depth of tumor invasion and differen a on of tumor correlated closely with LNM were iden fied by detec ng telomere length. The rates of LNM iden fied by detec ng telomere length were 34. 4%, 22. 4%, 22. 9%, 5. 0% in 108, 107, 7, and 3 LN sta on, respec vely. The number of LNM iden fied by detec ng telomere length was more closely related to the prognosis of ESCC than that of pathological examina on (HR: 1. 23 VERSUS 1. 04). Conclusion: The change of telomere length in LN was closely related to the prognosis of ESCC. Delinea on of clinical target volume (CTV) may benefit from the detec on of telomere length in regional LN.

Background: To correct pa ent posi oning errors (setup errors) during prostate cancer treatment using EPID and fiducial gold markers, to improve the accuracy of the dose delivery in these pa ents. Materials and Methods: Fi"een pa ents with localized prostate carcinoma a"er implanta on of fiducial gold markers in their prostate gland underwent the five-field IMRT planning technique. The plan was prepared in accordance with ICRU 50 guidance (PTV to receive 95-107% dose). The so"ware program reconstructed the three-dimensional posi on of the markers from the different Beams Eye Views (BEV). The discrepancies of the seeds’ posi ons (prostate surrogate) between plan and daily images were calculated three dimensionally. Then, necessary correc ons were applied to match the prostate fiducial markers in the portal image with the BEV image in the planned one by moving the couch in the X, Y and Z direc ons. Results: Data from 15 pa ents and 469 frac ons of radiotherapy were analyzed in this study. Two sets of data were available from EPID so"ware before and a"er 3D set-up correc ons. The mean of the popula on displacement in Le" /Right (L/R), Anterior/Posterior (A/P) and Crania/Caudal (C/C) direc ons were 0. 5,-1. 0 and 2. 4mm before, and-0. 1,-0. 5 and 0. 9mm a"er correc ons, respec vely. The systema c and random errors for the measured popula ons in the three men oned direc ons were 2. 4, 2. 7 and 2mm and 6. 4, 5. 9 and 6. 1mm before correc ons, and 1. 1, 2. 4 and 1. 4mm and 3. 8, 3. 9 and 3. 6mm a"er correc ons, correspondingly. Conclusion: This study provides further evidence that using gold markers in the prostate improves dose delivery to the prostate. Also, it has been demonstrated that the EPID can be a powerful tool in the reduc on of treatment setup errors and the quality assurance and verifica on of complex treatments.

Background: A method to track liver tumor motion signals from fluoroscopic images without any implanted gold fiducial markers was proposed in this study to overcome the adverse effects on precise tumor irradiation caused by respiratory movement. Materials and Methods: The method was based on the following idea: (i) Before treatment, a series of fluoroscopic images corresponding to different breathing phases and tumor positions were acquired after patient set-up; (iii) The wavelet transform method and Canny edge detection algorithm were used to detect motion trajectory of the diaphragm; (iv) The motion curves of center of lipiodol in the images were obtained by mathematical morphology and median filtering algorithm. The method was evaluated using by five sequences of fluoroscopic images from TACE patients who received transcatheter arterial chemoembolization therapy. Results: The position of liver tumor was significantly affected by respiratory motion; the motion trajectories of the diaphragm and lipiodolagreed well with the manually marked locations in amplitude and period; the motion trajectories of the diaphragm and lipiodol almost had similar period and amplitude in one treatment fraction. The respiratory period and amplitude of the same patient in different fractions had no significant differences; however, the difference was obvious for different patients. The proposed lipiodol detection methods can effectively reflect the relevant rules of tumor location caused by respiratory movement. Conclusion: Direct tracking of liver tumor motion in fluoroscopic images is feasible. The automatic detection method can reflect the characteristics of respiratory and tumor motions, which can save much time and significantly improve measurement precision compared with manual measurement.

Background: The health effect of rapidly increasing everyday exposure of humans to radiofrequency radia on is a major global concern. Mobile phone jammers prevent the mobile phones from receiving signals from base sta ons by interfering with authorized mobile carriers’ services. In spite of the fact that mobile jammer use is illegal, they are occasionally used in offices, shrines, conference rooms and cinemas. The purpose of this study was to inves gate the biological effects of short term exposure of human sperm to radiofrequency radia on emi$ed from a commercial mobile phone jammer. Materials and Methods: Fresh semen samples were obtained by masturba on from 50 healthy donors who had referred with their wives to Infer lity Treatment Center at the Mother and Child Hospital, Shiraz University of Medical Sciences. Female problem was diagnosed as the reason for infer lity in these couples. The semen sample of each par cipant was divided into 4 aliquots. The first aliquot was subjected to swim-up and exposed to jammer radia on. The second aliquot was not subjected to swimup but was exposed to jammer radia on. The third and fourth aliquots were not exposed to jammer radia on but only the 3rd aliquot was subjected to swim-up. Results: Semen samples exposed to radiofrequency radia on showed a significant decrease in sperm mo lity and increase in DNA fragmenta on. Conclusion: Electromagne c radia on in radiofrequency range emi$ed from mobile phone jammers may lead to decreased mo lity and increased DNA fragmenta on in human semen. It can be concluded that mobile phone jamming might exert adverse reproduc ve health effects.

Background: Human activities such as mining enhance the radioactivity levels above normal background which can lead to an incremental increase in the radiation risk to the population. Materials and Methods: 20 tailing enriched soil samples collected around Maiganga coal mine, Gombe, Northeast Nigeria were assessed for their 226Ra, 232Th and 40K contents using HPGe gamma-ray detector. Results: The mean activity values of 11. 90± 3. 0, 17. 72± 3. 6 and 70. 44± 20. 4 Bq kg-1 were obtained for 226Ra, 232Th and 40K respectively. These values were below the world average values documented by UNSCEAR. The ratio of 232Th: 226Ra obtained was 1. 5, which showed that 232Th activity was higher than the activity of 226Ra while 40K recorded the highest activity concentration in the studied samples. Statistical analysis identified strong positive relationships among all radiological parameters and confirmed that 226Ra, 232Th and 40K were the major contributors to radiation dose. Radium equivalent activity (Raeq), absorbed gamma dose rate (DR), annual effective dose (AEDE), activity utilization index (AUI), external and internal hazard indices (Hex and Hin), gamma representative index (Iγ r), annual gonadal dose (AGDE) and excess lifetime cancer risk (ELCR) were calculated to quantify the radiation risk to the public from exposure to 226Ra, 232Th and 40K in the studied samples. The mean values of these hazard parameters were within the acceptable limits provided for human safety and environmental protection. Conclusion: The use of the tailing enriched soil samples of Maiganga coal mine for any purpose whatsoever does not therefore pose any immediate radiological risk to the coal workers or the general public.

Background: Radon is one of the most important radioactive elements which is released by natural decay of available uranium and radium in the ground. The presence of radon gas is common, wherever those faults are located there. Radon concentration of various drinking water resources of Bam villages; located near Bam fault; was measured. Materials and Methods: This cross-sectional study was conducted in the spring of 2014. Samples were collected from 27 water resources (wells and canals) as well as 5 water storage tanks of Bam villages of Kerman province. The radon concentrations were determined by RAD7 device. The annual absorbed dose was also calculated according to the measured radon levels. Results: The average of minimum radon concentration in water resources was 1. 2 BqL-1; which was related to a water tank in Baravat; and the average of its maximum amount was calculated as 9. 88 BqL-1 which was related to a private home well in Baghchamak village. The maximum annual effective dose for adults was 30. 82 μ SvY-1and the lowest was calculated as 3. 74 μ SvY-1. Conclusion: Based on the achieved results, radon concentration of drinking water resources is lower than permitted concentration of EPA and also WHO guidelines.

Background: In response to the need for diagnosis and treatment, medical radiation has been increasingly used worldwide. This study investigated the medical utilization of radiation-related diseases among radiological technologists (RTs) and factors that influence such diseases. Materials and Methods: Data were collected from the Taiwan National Health Insurance Research Database. A panel study was conducted with a sample of 3, 432 RTs obtained in 2007 and followed up until 2011. Logistic regression applying generalized estimating equations was used for investigating the relationship between RTs and radiation-related diseases. Results: Among the RTs, the annual medical utilization rate of hospitalization for radiation-related neoplasms was 1. 17‰-4. 43‰ , that for circulatory diseases was 4. 68‰-11. 50‰ , and the annual medical utilization rate of outpatient visits for cataracts was 2. 91‰-7. 38‰ . After sex, age, hospital accreditation level, and hospital ownership were controlled, the odds of hospitalization for neoplasms and circulatory diseases among the RTs were nonsignificantly higher than those of pharmacists, and the odds of outpatient visits for cataracts among the RTs were nonsignificantly lower than those of pharmacists. Conclusion: No sufficient evidence exists to substantiate the argument that the exposure of RTs to current doses of radiation could increase the risk of neoplasms, circulatory diseases, and cataracts. Considering the increased use of radiation treatment in current medical facilities, all speculation on occupational radiation-induced diseases must be further investigated and verified.

Background: Intraoral radiographs are believed to deliver low doses to pa ents, thus li le work has been done in this regards. Considering the increment in the number of pa ents repor ng for the examina on and the probability of delayed soma c effects for accumulated low doses of Xirradia  on, it is expedient to determine the doses to three cri cal organs eye, thyroid and paro d that are at risk during exposure. Materials and Methods: Thermoluminescent dosimeters was used to measure Entrance Surfaces Doses (ESDs) to the thyroid, eye and paro ds salivary gland of 40 adult pa ents undergoing intra-oral radiographic examina on at University College Hospital, (UCH) Ibadan, Oyo state. Results: Results indicated entrance surface doses (ESD) ranged between 0. 0447 mGy to 0. 3898 mGy to the thyroid, 0. 0742 mGy to 0. 3989 mGy to eye and 0. 0467 mGy to 0. 4164 mGy to the paro ds for the period of study. The mean ESD ± SD to the thyroid, paro ds and eyes for male were 0. 1798± 0. 081, 0. 2155± 0. 109 and 0. 2197± 0. 081 mGy with the female pa ents 0. 1957± 0. 084, 0. 2091± 0. 081 and 0. 2280± 0. 113 mGy respec vely. No sta s cally significant difference was found between these means. Conclusion: The doses obtained in this study were lower than the documented threshold that could cause significant damage in the various organs, not undermining stochas c effect of radia on. This study will assist in se: ng Diagnos c Reference Level (DRL) for intraoral radiographic imaging in Nigeria.

4-Methylimidazole (4-MEI) is a simple nitrogen-containing heterocyclic compound, and recently classified as group 2B by Interna onal Agency for Research on Cancer (IARC). Caramel coloring is widely applied food coloring in many food products including coffee, carbonated beverages, beer and wine. In present study, γ-irradia on was applied to Caramel Color III to reduce the level of 4-MEI without color changes. Caramel coloring III was ɣ-irradiated with 1, 3, 5, 10, 30, 50 and 100 kGy. Non-irradiated caramel coloring was served as a control. The level of 4-MEI and color were analyzed on all caramel coloring. The concentra on of 4-MEI in the non-irradiated caramel coloring was 714. 9 mg/kg. The level of 4-MEI in caramel coloring was significantly reduced from 3 kGy ɣ-irradiated caramel coloring (p<0. 05). A7er 100 kGy irradia on, the amount of 4-MEI in caramel color was at 658 mg/kg, which equates 7. 9% reduc on from non-irradiated sample. No color change was observed on irradiated and non-irradiated caramel coloring (p>0. 05). Therefore, γ-irradia on could be used as an alterna ve processing method to improve the quality of caramel coloring by reducing 4-MEI content without its color change.

60-year-old woman was treated for a brain metastasis. The pa ent received intensity-modulated radia on therapy (SIB-IMRT) dose of 30 Gy for the whole brain and 40 Gy delivered simultaneously to individual brain metastases in 10 frac ons. The present report inves gated the influence of applied novel prepared treatment plan, among others the frac ona on protocol on the electroencephalogram (EEG) record.

Background: The purpose of this study was to inves gate the various gantry angle and SSD dependencies of TLD and MOSFET dosimeters. Materials and Methods: LiF (Mg) TLD and MOSFET were used in this study. Dosimeter systems were calibrated and then irradiated at various gantry angle and SSD by applying 6 MV photon energy. Results: Based on the results, MOSFET changes were found to be in 2% range between ± 50º gantry angles and the rate of dose change was found to be increasing as gantry angle was at the extremes of graph. This increase was especially obvious in tail end of the asymmetric axes. Change in the gantry angle dependency of TLD was-2%  ll ± 60º gantry angle and-5% between 60º to 90º . Dependency of SSD was ± 1% for TLD and MOSFET. Conclusion: Results indicate that proper es of dosimeters must be well known by users for accurate determina on of the en re doses on the pa ent. These observa ons may lead to be4er treatment quality and preven on of probable dose errors.

Background: In radiation therapy, water is the phantom material of choice, both for reference and for relative dosimetry measurements. Solid phantoms, however, are more useful for routine measurements because they tend to be more robust and easier to set up than water phantoms. Materials and Methods: FLUKA input data cards have been arranged in sequential order. A simple cylindrical geometry with the axis along the z-direction was described in the input file. A beam of 1x105 gamma-rays was directed towards the materials in the z-direction. The results of photon transmission, I/I0, were obtained from output files for each of the material thicknesses using the USRBDX score card. The USRBIN score card was also included in the input file, and the energy deposited by 661. 6 keV photons into water and solid phantom materials has been obtained. Results: The values of linear attenuation coefficients calculated by FLUKA are closer to experimentally obtained ones. The values of the linear attenuation coefficients derived from XCOM are greater than those derived from the FLUKA transmission data. The values of dose absorbed in Perspex are smaller than those of other materials, which are closer to each other. Conclusion: RMI-457, plastic water and RW solid phantoms can be used for radiation dosimetry of photons in the energy range from 59. 5 to 1332. 5 keV. From the investigation of absorbed dose values versus thickness of absorber, Perspex is not a suitable equivalent to water for the tested energies.