Displaying publications 1 - 20 of 28 in total

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  1. Photon dose rate distribution inside and outside a brachytherapy room
    Aminordin Sabri AH, Mohamad Tajudin S, Abdul Aziz MZ, Furuta T
    Radiol Phys Technol, 2023 Mar;16(1):109-117.
    PMID: 36729272 DOI: 10.1007/s12194-023-00703-8
    In a brachytherapy room irradiated with an Iridium-192 (192Ir) source, the spatial distributions of photon dose rates were measured and calculated for the dose distribution both inside and outside the room. The spatial distributions were measured using a thermoluminescent dosimeter (LiF-100) on the surfaces of the concrete walls and barriers of the irradiation room. The calculations were performed using the particle and heavy ion transport code system (PHITS) by considering the detailed model of the brachytherapy room and the radiation source used in the measurements. The measured and calculated doses exhibited a similar distribution pattern within and outside the brachytherapy room. To reduce the edge effect at the entrance door, the addition of a 3-mm thick lead layer on the surface of the concrete wall on the left doorstop is recommended. For the 60Co source, with the existing walls and lead door thickness, the dose at the control console and in front of the entrance maze increased by a factor of approximately 60.
    Matched MeSH terms: Brachytherapy*
  2. Fulltext Experimental study on mixed convection heat transfer in a square duct with varying inclination angles
    G. Rajamohan, R. Narayanaswamy, P. Kumar
    Pertanika Journal of Science & Technology, 2015;23(1):141-151.
    MyJurnal
    This study analysed mixed convection heat transfer for thermally developing flow in a side heated square duct with varying inclination angles. The test section consists of one-side heated isothermal wall and three adiabatic walls. The inclination angle varied from 00C, and heat flux ranging from 252 W/m2C to 100o30o 858 to 1788 and the wall surface emissivity was considered to be 0.05 and 0.85. Flow visualizations were carried out to obtain the flow structure of natural convection and mixed convection for three inclination angles. The variation of surface temperature along the length of the test section was studied to calculate the convective Nusselt number. The result showed that the heat transfer enhancement and convective Nusselt number was significantly affected by the variations of inclination angle, flow velocity, Reynolds number, and the surface radiation. It was also observed that the increase in the inclination angle improved convection rate and hence significantly enhanced heat transfer. to 200, with hot wall temperature ranging from to 872 W/m2
    Matched MeSH terms: Brachytherapy
  3. Dosimetric characterisation of the optically-stimulated luminescence dosimeter in cobalt-60 high dose rate brachytherapy system
    Rejab M, Wong JHD, Jamalludin Z, Jong WL, Malik RA, Wan Ishak WZ, et al.
    Australas Phys Eng Sci Med, 2018 Jun;41(2):475-485.
    PMID: 29756166 DOI: 10.1007/s13246-018-0647-6
    This study investigates the characteristics and application of the optically-stimulated luminescence dosimeter (OSLD) in cobalt-60 high dose rate (HDR) brachytherapy, and compares the results with the dosage produced by the treatment planning system (TPS). The OSLD characteristics comprised linearity, reproducibility, angular dependence, depth dependence, signal depletion, bleaching rate and cumulative dose measurement. A phantom verification exercise was also conducted using the Farmer ionisation chamber and in vivo diodes. The OSLD signal indicated a supralinear response (R2 = 0.9998). It exhibited a depth-independent trend after a steep dose gradient region. The signal depletion per readout was negligible (0.02%), with expected deviation for angular dependence due to off-axis sensitive volume, ranging from 1 to 16%. The residual signal of the OSLDs after 1 day bleached was within 1.5%. The accumulated and bleached OSLD signals had a standard deviation of ± 0.78 and ± 0.18 Gy, respectively. The TPS was found to underestimate the measured doses with deviations of 5% in OSLD, 17% in the Farmer ionisation chamber, and 7 and 8% for bladder and rectal diode probes. Discrepancies can be due to the positional uncertainty in the high-dose gradient. This demonstrates a slight displacement of the organ at risk near the steep dose gradient region will result in a large dose uncertainty. This justifies the importance of in vivo measurements in cobalt-60 HDR brachytherapy.
    Matched MeSH terms: Brachytherapy*
  4. Characterization of MOSkin detector for in vivo dose verification during Cobalt-60 high dose-rate intracavitary brachytherapy
    Jamalludin Z, Jong WL, Abdul Malik R, Rosenfeld A, Ung NM
    Phys Med, 2019 Feb;58:1-7.
    PMID: 30824140 DOI: 10.1016/j.ejmp.2019.01.010
    In vivo dosimetry in high dose-rate (HDR) intracavitary brachytherapy (ICBT) is important for assessing the true dose received by surrounding organs at risk during treatment. It also serves as part of the treatment delivery quality assurance and verification program with the use of a suitable dosimeter. Such a dosimeter should be characterized under brachytherapy conditions before clinical application to ensure the accuracy of in vivo measurement. In this study, a MOSFET-based detector, MOSkin, was calibrated and characterized under HDR Cobalt-60 (Co-60) brachytherapy source. MOSkin possessed the major advantages of having small physical and dosimetric sizes of 4.8 × 10-6 mm3 with the ability to provide real-time measurements. Using solid water and polymethyl methacrylate (PMMA) phantom, the detectors' reproducibility, linearity, angular and distance dependency was tested for its suitability as an in vivo detector. Correction factors to account for differences in depth measurements were determined. The MOSkin detector showed a reliable response when tested under Co-60 brachytherapy range of doses with an excellent linearity of R2 = 0.9997 and acceptable reproducibility. A phantom verification study was also conducted to verify the differences between MOSkin responses and treatment planning (TPS) calculated doses. By taking into account several correction factors, deviations ranging between 0.01 and 0.4 Gy were found between MOSkin measured and TPS doses at measurement distance of 20-55 mm. The use of MOSkin as the dosimeter of choice for in vivo dosimetry under Co-60 brachytherapy condition is feasible.
    Matched MeSH terms: Brachytherapy*
  5. Fulltext Experience of radioactive needle implants in the Institute of Radiotherapy Hospital Kuala Lumpur
    Lim GC, Azhar MT
    Med J Malaysia, 1997 Mar;52(1):33-7.
    PMID: 10968051
    This retrospective study of radioactive needle implants at the Institute of Radiotherapy and Oncology, Kuala Lumpur Hospital serves as an audit of our practice as well as a demonstration of the usefulness of this technique of brachytherapy. A variety of tumour sites were implanted, of which over two-thirds involved the tongue and buccal mucosa. Although most of the implants were carried out with radical intent, one-tenth of these implants were performed for palliation. Radiotherapy techniques employed are described. The crude survival ranged from 1 month to 109 months while the disease free interval ranged from 0 months to 102 months.
    Matched MeSH terms: Brachytherapy*
  6. Correlation analysis of CT-based rectal planning dosimetric parameters with in vivo dosimetry of MOSkin and PTW 9112 detectors in Co-60 source HDR intracavitary cervix brachytherapy
    Jamalludin Z, Malik RA, Ung NM
    Phys Eng Sci Med, 2021 Sep;44(3):773-783.
    PMID: 34191272 DOI: 10.1007/s13246-021-01026-x
    Intracavitary cervical brachytherapy delivers high doses of radiation to the target tissue and a portion of these doses will also hit the rectal organs due to their close proximity. Rectal dose can be evaluated from dosimetric parameters in the treatment planning system (TPS) and in vivo (IV) dose measurement. This study analyzed the correlation between IV rectal dose with selected volume and point dose parameters from TPS. A total of 48 insertions were performed and IV dose was measured using the commercial PTW 9112 semiconductor diode probe. In 18 of 48 insertions, a single MOSkin detector was attached on the probe surface at 50 mm from the tip. Four rectal dosimetric parameters were retrospectively collected from TPS; (a) PTW 9112 diode maximum reported dose (RPmax) and MOSkin detector, (b) minimum dose to 2 cc (D2cc), (c) ICRU reference point (ICRUr), and (d) maximum dose from additional points (Rmax). The IV doses from both detectors were analyzed for correlation with these dosimetric parameters. This study found a significantly high correlation between IV measured dose from RPmax (r = 0.916) and MOSkin (r = 0.959) with TPS planned dose. The correlation between measured RPmax with both D2cc and Rmax revealed high correlation of r > 0.7, whereas moderate correlation (r = 0.525) was observed with ICRUr. There was no significant correlation between MOSkin IV measured dose with D2cc, ICRUr and Rmax. The non-significant correlation between parameters was ascribable to differences in both detector position within patients, and dosimetric volume and point location determined on TPS, rather than detector uncertainties.
    Matched MeSH terms: Brachytherapy*
  7. Monte Carlo skin dose simulation in intraoperative radiotherapy of breast cancer using spherical applicators
    Moradi F, Ung NM, Khandaker MU, Mahdiraji GA, Saad M, Abdul Malik R, et al.
    Phys Med Biol, 2017 Jul 28;62(16):6550-6566.
    PMID: 28708603 DOI: 10.1088/1361-6560/aa7fe6
    The relatively new treatment modality electronic intraoperative radiotherapy (IORT) is gaining popularity, irradiation being obtained within a surgically produced cavity being delivered via a low-energy x-ray source and spherical applicators, primarily for early stage breast cancer. Due to the spatially dramatic dose-rate fall off with radial distance from the source and effects related to changes in the beam quality of the low keV photon spectra, dosimetric account of the Intrabeam system is rather complex. Skin dose monitoring in IORT is important due to the high dose prescription per treatment fraction. In this study, modeling of the x-ray source and related applicators were performed using the Monte Carlo N-Particle transport code. The dosimetric characteristics of the model were validated against measured data obtained using an ionization chamber and EBT3 film as dosimeters. By using a simulated breast phantom, absorbed doses to the skin for different combinations of applicator size (1.5-5 cm) and treatment depth (0.5-3 cm) were calculated. Simulation results showed overdosing of the skin (>30% of prescribed dose) at a treatment depth of 0.5 cm using applicator sizes larger than 1.5 cm. Skin doses were significantly increased with applicator size, insofar as delivering 12 Gy (60% of the prescribed dose) to skin for the largest sized applicator (5 cm diameter) and treatment depth of 0.5 cm. It is concluded that the recommended 0.5-1 cm distance between the skin and applicator surface does not guarantee skin safety and skin dose is generally more significant in cases with the larger applicators.

    HIGHLIGHTS: • Intrabeam x-ray source and spherical applicators were simulated and skin dose was calculated. • Skin dose for constant skin to applicator distance strongly depends on applicator size. • Use of larger applicators generally results in higher skin dose. • The recommended 0.5-1 cm skin to applicator distance does not guarantee skin safety.

    Matched MeSH terms: Brachytherapy/instrumentation*; Brachytherapy/methods
  8. American Brachytherapy Society: Brachytherapy treatment recommendations for locally advanced cervix cancer for low-income and middle-income countries
    Suneja G, Brown D, Chang A, Erickson B, Fidarova E, Grover S, et al.
    Brachytherapy, 2017 Jan-Feb;16(1):85-94.
    PMID: 27919654 DOI: 10.1016/j.brachy.2016.10.007
    PURPOSE: Most cervix cancer cases occur in low-income and middle-income countries (LMIC), and outcomes are suboptimal, even for early stage disease. Brachytherapy plays a central role in the treatment paradigm, improving both local control and overall survival. The American Brachytherapy Society (ABS) aims to provide guidelines for brachytherapy delivery in resource-limited settings.

    METHODS AND MATERIALS: A panel of clinicians and physicists with expertise in brachytherapy administration in LMIC was convened. A survey was developed to identify practice patterns at the authors' institutions and was also extended to participants of the Cervix Cancer Research Network. The scientific literature was reviewed to identify consensus papers or review articles with a focus on treatment of locally advanced, unresected cervical cancer in LMIC.

    RESULTS: Of the 40 participants invited to respond to the survey, 32 responded (response rate 80%). Participants were practicing in 14 different countries including both high-income (China, Singapore, Taiwan, United Kingdom, and United States) and low-income or middle-income countries (Bangladesh, Botswana, Brazil, India, Malaysia, Pakistan, Philippines, Thailand, and Vietnam). Recommendations for modifications to existing ABS guidelines were reviewed by the panel members and are highlighted in this article.

    CONCLUSIONS: Recommendations for treatment of locally advanced, unresectable cervical cancer in LMIC are presented. The guidelines comment on staging, external beam radiotherapy, use of concurrent chemotherapy, overall treatment duration, use of anesthesia, applicator choice and placement verification, brachytherapy treatment planning including dose and prescription point, recommended reporting and documentation, physics support, and follow-up.
    Matched MeSH terms: Brachytherapy/methods*; Brachytherapy/standards
  9. Comparison of planned and measured rectal dose in-vivo during high dose rate Cobalt-60 brachytherapy of cervical cancer
    Zaman ZK, Ung NM, Malik RA, Ho GF, Phua VC, Jamalludin Z, et al.
    Phys Med, 2014 Dec;30(8):980-4.
    PMID: 25086486 DOI: 10.1016/j.ejmp.2014.07.002
    Cobalt-60 (Co-60) is a relatively new source for the application of high-dose rate (HDR) brachytherapy. Radiation dose to the rectum is often a limiting factor in achieving the full prescribed dose to the target during brachytherapy of cervical cancer. The aim of this study was to measure radiation doses to the rectum in-vivo during HDR Co-60 brachytherapy. A total of eleven HDR brachytherapy treatments of cervical cancer were recruited in this study. A series of diodes incorporated in a rectal probe was inserted into the patient's rectum during each brachytherapy procedure. Real-time measured rectal doses were compared to calculated doses by the treatment planning system (TPS). The differences between calculated and measured dose ranged from 8.5% to 41.2%. This corresponds to absolute dose differences ranging from 0.3 Gy to 1.5 Gy. A linear relationship was observed between calculated and measured doses with linear regression R(2) value of 0.88, indicating close association between the measured and calculated doses. In general, absorbed doses for the rectum as calculated by TPS were observed to be higher than the doses measured using the diode probe. In-vivo dosimetry is an important quality assurance method for HDR brachytherapy of cervical cancer. It provides information that can contribute to the reduction of errors and discrepancies in dose delivery. Our study has shown that in-vivo dosimetry is feasible and can be performed to estimate the dose to the rectum during HDR brachytherapy using Co-60.
    Matched MeSH terms: Brachytherapy/adverse effects; Brachytherapy/methods*
  10. Fulltext Brachytherapy of tongue carcinoma in a patient with difficult airway: anesthetic considerations
    Ghaffar ZA, Chong SE, Tan KL, Appalanaido GK, Musa MY, Hussin HB, et al.
    J Contemp Brachytherapy, 2018 Dec;10(6):573-576.
    PMID: 30662482 DOI: 10.5114/jcb.2018.79856
    The practice of brachytherapy in unresectable tongue carcinoma is gaining popularity. However, this procedure poses specific anesthetic challenges, particularly challenges of airway sharing and a higher rate of difficult airway. We report a 74-year-old chronic smoker, chronic alcoholic with history of stroke, who had undergone brachytherapy for tongue carcinoma. Apart from a huge tongue tumor, he had an epiglottic mass but refused elective tracheostomy. This had led to a few critical states throughout the process of treatment, including a metabolic crisis due to thiamine deficiency and difficult airway crisis. To our best knowledge, there have been no reported case on a patient with vocal cord mass undergoing tongue brachytherapy. We hope sharing of this experience may aid the management of similar patients in future.
    Matched MeSH terms: Brachytherapy
  11. Fulltext High dose rate intracavitary radiation therapy of carcinoma of the cervix using a linear source
    Azhar T, Kamada T, Lopez F, Harun R, Nor I, Lim A
    Med J Malaysia, 1991 Jun;46(2):123-8.
    PMID: 1839415
    One hundred patients with carcinoma of the cervix stages 1B to 4A were treated with intracavitary high dose rate radiation using a linear cobalt source. All cases have received external beam pelvic irradiation to 4500cGy mid plane in twenty fractions over four weeks. The results in terms of patient compliance and convenience were good while acute and late morbidities were comparable to standard Manchester technique of low dose rate intracavitary therapy as practised in the Institute of Radiotherapy and Oncology General Hospital Kuala Lumpur. The four year actuarial survival rate is 76% for stage II and 48% for stage III. All three stage IV patients died within 1 year. Four out of seven stage I patients are alive (minimum follow-up 18 months, longest 43 months). One died of systemic spread at 33 months while one is lost to follow up.
    Matched MeSH terms: Brachytherapy
  12. Cervix Cancer Research Network (CCRN): Improving Access to Cervix Cancer Trials on a Global Scale
    Gaffney D, Small B, Kitchener H, Young Ryu S, Viswanathan A, Trimble T, et al.
    Int. J. Gynecol. Cancer, 2016 11;26(9):1690-1693.
    PMID: 27779548
    Eighty-seven percent of cervix cancer occurs in less-developed regions of the world, and there is up to an 18-fold difference in mortality rate for cervix cancer depending on the region of the world. The Cervix Cancer Research Network (CCRN) was founded through the Gynecologic Cancer InterGroup with the aim of improving access to clinical trials in cervix cancer worldwide, and in so doing improving standards of care. The CCRN recently held its first international educational symposium in Bangkok. Sixty-two participants attended from 16 different countries including Pakistan, India, Bangladesh, Thailand, Malaysia, Singapore, Philippines, Taiwan, China, Vietnam, Korea, Japan, Columbia, Brazil, Canada, and the United States. The focus of this symposium was to evaluate progress, to promote new clinical trials for the CCRN, and to provide education regarding the role of brachytherapy in the treatment of cervical cancer.
    Matched MeSH terms: Brachytherapy
  13. Systematic investigation on the validity of partition model dosimetry for90Y radioembolization using Monte Carlo simulation
    Hashikin NAA, Yeong CH, Guatelli S, Abdullah BJJ, Ng KH, Malaroda A, et al.
    Phys Med Biol, 2017 Aug 22;62(18):7342-7356.
    PMID: 28686171 DOI: 10.1088/1361-6560/aa7e5b
    We aimed to investigate the validity of the partition model (PM) in estimating the absorbed doses to liver tumour ([Formula: see text]), normal liver tissue ([Formula: see text]) and lungs ([Formula: see text]), when cross-fire irradiations between these compartments are being considered. MIRD-5 phantom incorporated with various treatment parameters, i.e. tumour involvement (TI), tumour-to-normal liver uptake ratio (T/N) and lung shunting (LS), were simulated using the Geant4 Monte Carlo (MC) toolkit. 108track histories were generated for each combination of the three parameters to obtain the absorbed dose per activity uptake in each compartment ([Formula: see text], [Formula: see text], and [Formula: see text]). The administered activities, A were estimated using PM, so as to achieve either limiting doses to normal liver, [Formula: see text] or lungs, [Formula: see text] (70 or 30 Gy, respectively). Using these administered activities, the activity uptake in each compartment ([Formula: see text], [Formula: see text], and [Formula: see text]) was estimated and multiplied with the absorbed dose per activity uptake attained using the MC simulations, to obtain the actual dose received by each compartment. PM overestimated [Formula: see text] by 11.7% in all cases, due to the escaped particles from the lungs. [Formula: see text] and [Formula: see text] by MC were largely affected by T/N, which were not considered by PM due to cross-fire exclusion at the tumour-normal liver boundary. These have resulted in the overestimation of [Formula: see text] by up to 8% and underestimation of [Formula: see text] by as high as  -78%, by PM. When [Formula: see text] was estimated via PM, the MC simulations showed significantly higher [Formula: see text] for cases with higher T/N, and LS  ⩽  10%. All [Formula: see text] and [Formula: see text] by MC were overestimated by PM, thus [Formula: see text] were never exceeded. PM leads to inaccurate dose estimations due to the exclusion of cross-fire irradiation, i.e. between the tumour and normal liver tissue. Caution should be taken for cases with higher TI and T/N, and lower LS, as they contribute to major underestimation of [Formula: see text]. For [Formula: see text], a different correction factor for dose calculation may be used for improved accuracy.
    Matched MeSH terms: Brachytherapy/methods*
  14. Borosilicate glass 60Co high dose rate brachytherapy thermoluminescence dosimetry
    Nazeri AAZA, Sani SFA, Ung NM, Almugren KS, Alkallas FH, Bradley DA
    Appl Radiat Isot, 2021 Oct;176:109814.
    PMID: 34175543 DOI: 10.1016/j.apradiso.2021.109814
    Brachytherapy is commonly used in treatment of cervical, prostate, breast and skin cancers, also for oral cancers, typically via the application of sealed radioactive sources that are inserted within or alongside the area to be treated. A particular aim of the various brachytherapy techniques is to accurately transfer to the targeted tumour the largest possible dose, at the same time minimizing dose to the surrounding normal tissue, including organs at risk. The dose fall-off with distance from the sources is steep, the dose gradient representing a prime factor in determining the dose distribution, also representing a challenge to the conduct of measurements around sources. Amorphous borosilicate glass (B2O3) in the form of microscope cover slips is recognized to offer a practicable system for such thermoluminescence dosimetry (TLD), providing for high-spatial resolution (down to 
    Matched MeSH terms: Brachytherapy/methods*
  15. SIRveNIB: Selective Internal Radiation Therapy Versus Sorafenib in Asia-Pacific Patients With Hepatocellular Carcinoma
    Chow PKH, Gandhi M, Tan SB, Khin MW, Khasbazar A, Ong J, et al.
    J Clin Oncol, 2018 07 01;36(19):1913-1921.
    PMID: 29498924 DOI: 10.1200/JCO.2017.76.0892
    Purpose Selective internal radiation therapy or radioembolization (RE) shows efficacy in unresectable hepatocellular carcinoma (HCC) limited to the liver. This study compared the safety and efficacy of RE and sorafenib in patients with locally advanced HCC. Patients and Methods SIRveNIB (selective internal radiation therapy v sorafenib), an open-label, investigator-initiated, phase III trial, compared yttrium-90 (90Y) resin microspheres RE with sorafenib 800 mg/d in patients with locally advanced HCC in a two-tailed study designed for superiority/detriment. Patients were randomly assigned 1:1 and stratified by center and presence of portal vein thrombosis. Primary end point was overall survival (OS). Efficacy analyses were performed in the intention-to-treat population and safety analyses in the treated population. Results A total of 360 patients were randomly assigned (RE, 182; sorafenib, 178) from 11 countries in the Asia-Pacific region. In the RE and sorafenib groups, 28.6% and 9.0%, respectively, failed to receive assigned therapy without significant cross-over to either group. Median OS was 8.8 and 10.0 months with RE and sorafenib, respectively (hazard ratio, 1.1; 95% CI, 0.9 to 1.4; P = .36). A total of 1,468 treatment-emergent adverse events (AEs) were reported (RE, 437; sorafenib, 1,031). Significantly fewer patients in the RE than sorafenib group had grade ≥ 3 AEs (36 of 130 [27.7%]) v 82 of 162 [50.6%]; P < .001). The most common grade ≥ 3 AEs were ascites (five of 130 [3.8%] v four of 162 [2.5%] patients), abdominal pain (three [2.3%] v two [1.2%] patients), anemia (zero v four [2.5%] patients), and radiation hepatitis (two [1.5%] v zero [0%] patients). Fewer patients in the RE group (27 of 130 [20.8%]) than in the sorafenib group (57 of 162 [35.2%]) had serious AEs. Conclusion In patients with locally advanced HCC, OS did not differ significantly between RE and sorafenib. The improved toxicity profile of RE may inform treatment choice in selected patients.
    Matched MeSH terms: Brachytherapy
  16. Fulltext Bystander Effect Induced in Breast Cancer (MCF-7) and Human Osteoblast Cell Lines (hFOB 1.19) with HDR-Brachytherapy
    Zainudin Nh M, R A, W N R
    J Biomed Phys Eng, 2020 Jun;10(3):319-328.
    PMID: 32637376 DOI: 10.31661/jbpe.v0i0.1135
    Background: Radiation induced bystander effects (RIBEs) occurs in unirradiated cells exhibiting indirect biological effect as a consequence of signals from other irradiated cells in the population.

    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.

    Matched MeSH terms: Brachytherapy
  17. Fulltext Hole on the palate, saliva in the nose: what is your diagnosis?
    Irfan Mohamad, Shamina Sara Moses, Rose linda Abdul Rahman
    Archives of Orofacial Sciences, 2013;8(1):44-45.
    MyJurnal
    A 69-year-old lady was diagnosed to have mucoepidermoid carcinoma of hard palate 3 years ago. She completed 20 cycles of external beam radiotherapy and 5 cycles of mould brachytherapy and remained asymptomatic until she again presented to us with the recurrence of a painless mass at the hard palate. The hard mass appeared as an ulcerated dimple measuring 2 x 1 cm located at the junction of the hard and soft palate, more towards the right. Excision biopsy of the mass was done with a 1cm circumferential margin deep to the periosteum, with the resulting exposed bony defect covered with a rotational flap from the soft palate. During follow-up, the patient complained that the saliva came up into the nose whenever she swallowed. Oral examination (Figure 1) and flexible nasopharyngolaryngoscopy (FNPLS) (Figure 2) were performed. What is your diagnosis?
    Matched MeSH terms: Brachytherapy
  18. Fulltext Case Report-Staged brachytherapy achieving complete metabolic response in unresectable oligometastatic colorectal cancer to the liver
    Appalanaido GK, Bahajjaj SIBZ, Shukor SA, Ahmad MZ, Francis HCH
    Oxf Med Case Reports, 2021 Apr;2021(4):omab016.
    PMID: 33948189 DOI: 10.1093/omcr/omab016
    Liver is the most common site for metastasis from colorectal cancer (CRC). Non-surgical treatment options for oligometastatic CRC confined to the liver which represents an intermediate state in the metastatic cascade are fast expanding. Currently, several liver-directed local therapeutic options are available, such as hepatic arterial infusion (HAI) therapy, radio-frequency ablation (RFA), transarterial chemoembolization (TACE), stereotactic body radiotherapy and high dose rate brachytherapy (HDRBT). Many factors such as patient's fitness, liver function (LF), tumour size, location of the tumour in the liver and scheduling of systemic therapy need to be considered when selecting patients for surgery or local liver-directed therapy. This case report illustrates a successful local treatment with staged HDRBT for a large and unresectable, liver only oligometastatic disease from CRC. This patient underwent 4 cycles of chemotherapy (FOLFOX 4) followed by primary tumour resection and first stage of HDRBT to liver for a residual 14 cm tumour after the chemotherapy. After completing a further 4 cycles of chemotherapy with the same regimen, the tumour remained stable at 8 cm. She underwent a second stage of HDRBT to the same lesion and a repeat PET-CT scan done 8 weeks after the second HDRBT showed complete metabolic response. To our knowledge, this is the largest CRC metastatic liver lesion that has been successfully treated with HDRB.
    Matched MeSH terms: Brachytherapy
  19. Evaluation of rectal dose discrepancies between planned and in vivo dosimetry using MOSkin detector and PTW 9112 semiconductor probe during 60Co HDR CT-based intracavitary cervix brachytherapy
    Jamalludin Z, Jong WL, Malik RA, Rosenfeld AB, Ung NM
    Phys Med, 2020 Jan;69:52-60.
    PMID: 31830631 DOI: 10.1016/j.ejmp.2019.11.025
    PURPOSE: Dose to the rectum during brachytherapy treatment may differ from an approved treatment plan which can be quantified with in vivo dosimetry (IVD). This study compares the planned with in vivo doses measured with MOSkin and PTW 9112 rectal probe in patients undergoing CT based HDR cervical brachytherapy with Co-60 source.

    METHODS: Dose measurement of a standard pear-shaped plan carried out in phantom to verify the MOSkin dose measurement accuracy. With MOSkin attached to the third diode, RP3 of the PTW 9112, both detectors were inserted into patients' rectum. The RP3 and MOSkin measured doses in 18 sessions as well as the maximum measured doses from PTW 9112, RPmax in 48 sessions were compared to the planned doses.

    RESULTS: Percentage dose differences ΔD (%) in phantom study for two MOSkin found to be 2.22 ± 0.07% and 2.5 ± 0.07%. IVD of 18 sessions resulted in ΔD(%) of -16.3% to 14.9% with MOSkin and ΔD(%) of -35.7% to -2.1% with RP3. In 48 sessions, RPmax recorded ΔD(%) of -37.1% to 11.0%. MOSkin_measured doses were higher in 44.4% (8/18) sessions, while RP3_measured were lower than planned doses in all sessions. RPmax_measured were lower in 87.5% of applications (42/47).

    CONCLUSIONS: The delivered doses proven to deviate from planned doses due to unavoidable shift between imaging and treatment as measured with MOSkin and PTW 9112 detectors. The integration of MOSkin on commercial PTW 9112 surface found to be feasible for rectal dose IVD during cervical HDR ICBT.

    Matched MeSH terms: Brachytherapy/methods*
  20. Fulltext Synergetic Influence of Bismuth Oxide Nanoparticles, Cisplatin and Baicalein-Rich Fraction on Reactive Oxygen Species Generation and Radiosensitization Effects for Clinical Radiotherapy Beams
    Talik Sisin NN, Abdul Razak K, Zainal Abidin S, Che Mat NF, Abdullah R, Ab Rashid R, et al.
    Int J Nanomedicine, 2020;15:7805-7823.
    PMID: 33116502 DOI: 10.2147/IJN.S269214
    Purpose: This study aimed to quantify synergetic effects induced by bismuth oxide nanoparticles (BiONPs), cisplatin (Cis) and baicalein-rich fraction (BRF) natural-based agent on the reactive oxygen species (ROS) generation and radiosensitization effects under irradiation of clinical radiotherapy beams of photon, electron and HDR-brachytherapy. The combined therapeutic responses of each compound and clinical radiotherapy beam were evaluated on breast cancer and normal fibroblast cell line.

    Methods: In this study, individual BiONPs, Cis, and BRF, as well as combinations of BiONPs-Cis (BC), BiONPs-BRF (BB) and BiONPs-Cis-BRF (BCB) were treated to the cells before irradiation using HDR brachytherapy with 0.38 MeV iridium-192 source, 6 MV photon beam and 6 MeV electron beam. The individual or synergetic effects from the application of the treatment components during the radiotherapy were elucidated by quantifying the ROS generation and radiosensitization effects on MCF-7 and MDA-MB-231 breast cancer cell lines as well as NIH/3T3 normal cell line.

    Results: The ROS generated in the presence of Cis stimulated the most substantial amount of ROS compared to the BiONPs and BRF. Meanwhile, the combination of the components had induced the higher ROS levels for photon beam than the brachytherapy and electron beam. The highest ROS enhancement relative to the control is attributable to the presence of BC combination in MDA-MB-231 cells, in comparison to the BB and BCB combinations. The radiosensitization effects which were quantified using the sensitization enhancement ratio (SER) indicate the highest value by BC in MCF-7 cells, followed by BCB and BB treatment. The radiosensitization effects are found to be more prominent for brachytherapy in comparison to photon and electron beam.

    Conclusion: The BiONPs, Cis and BRF are the potential radiosensitizers that could improve the efficiency of radiotherapy to eradicate the cancer cells. The combination of these potent radiosensitizers might produce multiple effects when applied in radiotherapy. The BC combination is found to have the highest SER, followed by the BCB combination. This study is also the first to investigate the effect of BRF in combination with BiONPs (BB) and BC (BCB) treatments.

    Matched MeSH terms: Brachytherapy*
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