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Radiotherapy and Oncology : Journal of... Feb 2022This is an evidence-based guideline for prostate brachytherapy. Throughout levels of evidence quoted are those from the Oxford Centre for Evidence based Medicine...
This is an evidence-based guideline for prostate brachytherapy. Throughout levels of evidence quoted are those from the Oxford Centre for Evidence based Medicine (https://www.cebm.ox.ac.uk/resources/levels-of-evidence/oxford-centre-for-evidence-based-medicine-levels-of-evidence-march-2009). Prostate interstitial brachytherapy using either permanent or temporary implantation is an established and evolving treatment technique for non-metastatic prostate cancer. Permanent brachytherapy uses Low Dose Rate (LDR) sources, most commonly I-125, emitting photon radiation over months. Temporary brachytherapy involves first placing catheters within the prostate and, on confirmation of accurate positioning, temporarily introducing the radioactive source, generally High Dose Rate (HDR) radioactive sources of Ir-192 or less commonly Co-60. Pulsed dose rate (PDR) brachytherapy has also been used for prostate cancer [1] but few centres have adopted this approach. Previous GEC ESTRO recommendations have considered LDR and HDR separately [2-4] but as there is considerable overlap, this paper provides updated guidance for both treatment techniques. Prostate brachytherapy allows safe radiation dose escalation beyond that achieved using external beam radiotherapy alone as it has greater conformity around the prostate, sparing surrounding rectum, bladder, and penile bulb. In addition there are fewer issues with changes in prostate position during treatment delivery. Systematic review and randomised trials using both techniques as boost treatments demonstrate improved PSA control when compared to external beam radiotherapy alone [5-7].
Topics: Brachytherapy; Humans; Iodine Radioisotopes; Male; Prostate; Prostatic Neoplasms; Radiotherapy Dosage
PubMed: 34999134
DOI: 10.1016/j.radonc.2021.12.047 -
Fertility and Sterility Feb 2020To provide evidence-based recommendations to practicing physicians and others regarding the effectiveness and safety of therapies for unexplained infertility.
OBJECTIVE
To provide evidence-based recommendations to practicing physicians and others regarding the effectiveness and safety of therapies for unexplained infertility.
METHODS
ASRM conducted a literature search, which included systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 1968 through 2019. The ASRM Practice Committee and a task force of experts used available evidence and informal consensus to develop evidence-based guideline recommendations.
MAIN OUTCOME MEASURE(S)
Outcomes of interest included: live-birth rate, clinical pregnancy rate, implantation rate, fertilization rate, multiple pregnancy rate, dose of treatment, rate of ovarian hyperstimulation, abortion rate, and ectopic pregnancy rate.
RESULT(S)
The literature search identified 88 relevant studies to inform the evidence base for this guideline.
RECOMMENDATION(S)
Evidence-based recommendations were developed for the following treatments for couples with unexplained infertility: natural cycle with intrauterine insemination (IUI); clomiphene citrate with intercourse; aromatase inhibitors with intercourse; gonadotropins with intercourse; clomiphene citrate with IUI; aromatase inhibitors with IUI; combination of clomiphene citrate or letrozole and gonadotropins (low dose and conventional dose) with IUI; low-dose gonadotropins with IUI; conventional-dose gonadotropins with IUI; timing of IUI; and in vitro fertilization and treatment paradigms.
CONCLUSION(S)
The treatment of unexplained infertility is by necessity empiric. For most couples, the best initial therapy is a course (typically 3 or 4 cycles) of ovarian stimulation with oral medications and intrauterine insemination (OS-IUI) followed by in vitro fertilization for those unsuccessful with OS-IUI treatments.
Topics: Aromatase Inhibitors; Clomiphene; Evidence-Based Practice; Female; Fertilization in Vitro; Gonadotropins; Humans; Infertility, Female; Insemination, Artificial; Pregnancy; Randomized Controlled Trials as Topic
PubMed: 32106976
DOI: 10.1016/j.fertnstert.2019.10.014 -
Translational Andrology and Urology Jun 2018Low dose rate (LDR) prostate brachytherapy is an evidence based radiation technique with excellent oncologic outcomes. By utilizing direct image guidance for radioactive... (Review)
Review
Low dose rate (LDR) prostate brachytherapy is an evidence based radiation technique with excellent oncologic outcomes. By utilizing direct image guidance for radioactive source placement, LDR brachytherapy provides superior radiation dose escalation and conformality compared to external beam radiation therapy (EBRT). With this level of precision, late grade 3 or 4 genitourinary or gastrointestinal toxicity rates are typically between 1% and 4%. Furthermore, when performed as a same day surgical procedure, this technique provides a cost effective and convenient strategy. A large body of literature with robust follow-up has led multiple expert consensus groups to endorse the use of LDR brachytherapy as an appropriate management option for all risk groups of non-metastatic prostate cancer. LDR brachytherapy is often effective when delivered as a monotherapy, although for some patients with intermediate or high-risk disease, optimal outcome are achieved in combination with supplemental EBRT and/or androgen deprivation therapy (ADT). In addition to reviewing technical aspects and reported clinical outcomes of LDR prostate brachytherapy, this article will focus on the considerations related to appropriate patient selection and other aspects of its use in the treatment of prostate cancer.
PubMed: 30050795
DOI: 10.21037/tau.2017.12.15 -
Radiation and Environmental Biophysics Nov 2022Despite decades of research to understand the biological effects of ionising radiation, there is still much uncertainty over the role of dose rate. Motivated by a... (Review)
Review
Despite decades of research to understand the biological effects of ionising radiation, there is still much uncertainty over the role of dose rate. Motivated by a virtual workshop on the "Effects of spatial and temporal variation in dose delivery" organised in November 2020 by the Multidisciplinary Low Dose Initiative (MELODI), here, we review studies to date exploring dose rate effects, highlighting significant findings, recent advances and to provide perspective and recommendations for requirements and direction of future work. A comprehensive range of studies is considered, including molecular, cellular, animal, and human studies, with a focus on low linear-energy-transfer radiation exposure. Limits and advantages of each type of study are discussed, and a focus is made on future research needs.
Topics: Animals; Humans; Radiation Protection; Radiation Dosage; Radiation Injuries; Radiation Exposure; Radiation, Ionizing; Radiobiology
PubMed: 36241855
DOI: 10.1007/s00411-022-00996-0 -
Frontiers in Oncology 2021The three-dimensional iridium-192 (Ir) high-dose-rate (HDR) brachytherapy manifests itself as a high-precision, hypofractionated, dose-escalating, minimally invasive... (Review)
Review
The three-dimensional iridium-192 (Ir) high-dose-rate (HDR) brachytherapy manifests itself as a high-precision, hypofractionated, dose-escalating, minimally invasive method in the armamentarium of contemporary radiation oncology clinical applications. In this study, the physical aspects of the Ir radionuclide are presented. Its dosimetric application in HDR brachytherapy for different anatomical sites (prostate, gynecological malignancies, liver, and intrathoracic tumors) as well as the corresponding dosimetric comparison with the stereotactic body radiation therapy (SBRT) techniques based on a representative selection of dosimetric publications is reviewed and illustrated.
PubMed: 34858815
DOI: 10.3389/fonc.2021.728452 -
Frontiers in Oncology 2022
PubMed: 35356219
DOI: 10.3389/fonc.2022.877165 -
Frontiers in Oncology 2021High-dose-rate brachytherapy by remote afterloading is now performed under three-dimensional image guidance by CT or MRI. Three-dimensional image-guided brachytherapy in... (Review)
Review
High-dose-rate brachytherapy by remote afterloading is now performed under three-dimensional image guidance by CT or MRI. Three-dimensional image-guided brachytherapy in cervical cancer disclosed that the traditional intracavitary brachytherapy by Manchester method cannot deliver an adequate dose to the large tumor with resulting local recurrence. To improve the local control rate, combined interstitial and intracavitary (hybrid) brachytherapy can increase the dose to the large parametrial involvement without increasing the dose to the rectum and bladder. Whether hybrid brachytherapy can be performed safely on a multi-institutional basis remains to be studied. From 2015, phase I/II study of hybrid brachytherapy was launched in Japan, and it was revealed that hybrid brachytherapy can be performed safely and with a high quality of radiation dose distribution in a multi-institutional study. In Japan, the number of patients undergoing hybrid brachytherapy in cervical cancer is rapidly rising. Education and clinical trial are very important to establish hybrid brachytherapy in the management of cervical cancer.
PubMed: 35096614
DOI: 10.3389/fonc.2021.809825 -
Cancers Dec 2021For more than two decades, stereotactic radiosurgery has been considered a cornerstone treatment for patients with limited brain metastases. Historically, radiosurgery... (Review)
Review
For more than two decades, stereotactic radiosurgery has been considered a cornerstone treatment for patients with limited brain metastases. Historically, radiosurgery in a single fraction has been the standard of care but recent technical advances have also enabled the delivery of hypofractionated stereotactic radiotherapy for dedicated situations. Only few studies have investigated the efficacy and toxicity profile of different hypofractionated schedules but, to date, the ideal dose and fractionation schedule still remains unknown. Moreover, the linear-quadratic model is being debated regarding high dose per fraction. Recent studies shown the radiation schedule is a critical factor in the immunomodulatory responses. The aim of this literature review was to discuss the dose-effect relation in brain metastases treated by stereotactic radiosurgery accounting for fractionation and technical considerations. Efficacy and toxicity data were analyzed in the light of recent published data. Only retrospective and heterogeneous data were available. We attempted to present the relevant data with caution. A BED10 of 40 to 50 Gy seems associated with a 12-month local control rate >70%. A BED10 of 50 to 60 Gy seems to achieve a 12-month local control rate at least of 80% at 12 months. In the brain metastases radiosurgery series, for single-fraction schedule, a V12 Gy < 5 to 10 cc was associated to 7.1-22.5% radionecrosis rate. For three-fractions schedule, V18 Gy < 26-30 cc, V21 Gy < 21 cc and V23 Gy < 5-7 cc were associated with about 0-14% radionecrosis rate. For five-fractions schedule, V30 Gy < 10-30 cc, V 28.8 Gy < 3-7 cc and V25 Gy < 16 cc were associated with about 2-14% symptomatic radionecrosis rate. There are still no prospective trials comparing radiosurgery to fractionated stereotactic irradiation.
PubMed: 34885193
DOI: 10.3390/cancers13236086 -
Scientific Reports Apr 2022Reproductive sterility is the basis of the sterile insect technique (SIT) and essential for its success in the field. Numerous factors that influence dose-response in...
Reproductive sterility is the basis of the sterile insect technique (SIT) and essential for its success in the field. Numerous factors that influence dose-response in insects have been identified. However, historically the radiation dose administered has been considered a constant. Efforts aiming to standardize protocols for mosquito irradiation found that, despite carefully controlling many variable factors, there was still an unknown element responsible for differences in expected sterility levels of insects irradiated with the same dose and handling protocols. Thus, together with previous inconclusive investigations, the question arose whether dose really equals dose in terms of biological response, no matter the rate at which the dose is administered. Interestingly, the dose rate effects studied in human nuclear medicine indicated that dose rate could alter dose-response in mammalian cells. Here, we conducted experiments to better understand the interaction of dose and dose rate to assess the effects in irradiated mosquitoes. Our findings suggest that not only does dose rate alter irradiation-induced effects, but that the interaction is not linear and may change with dose. We speculate that the recombination of reactive oxygen species (ROS) in treatments with moderate to high dose rates might minimize indirect radiation-induced effects in mosquitoes and decrease sterility levels, unless dose along with its direct effects is increased. Together with further studies to identify an optimum match of dose and dose rate, these results could assist in the development of improved methods for the production of high-quality sterile mosquitoes to enhance the efficiency of SIT programs.
Topics: Animals; Humans; Infertility; Insecta; Mammals; Pupa; Radiation Dosage
PubMed: 35422488
DOI: 10.1038/s41598-022-10027-z -
Cancer Reports (Hoboken, N.J.) Jan 2022High-dose-rate brachytherapy (HDR BRT) has been enjoying rapid acceptance as a treatment modality offered to selected prostate cancer patients devoid of risk group,... (Review)
Review
BACKGROUND
High-dose-rate brachytherapy (HDR BRT) has been enjoying rapid acceptance as a treatment modality offered to selected prostate cancer patients devoid of risk group, employed either in monotherapy setting or combined with external beam radiation therapy (EBRT) and is currently one of the most active clinical research areas.
RECENT FINDINGS
This review encompasses all the current evidence to support the use of HDR BRT in various clinical scenario and shines light to the HDR BRT rationale, as an ultimately conformal dose delivery method enabling safe dose escalation to the prostate.
CONCLUSION
Valid long-term data, both in regard to the oncologic outcomes and toxicity profile, support the current clinical indication spectrum of HDR BRT. At the same time, this serves as solid, rigid ground for emerging therapeutic applications, allowing the technique to remain in the spotlight alongside stereotactic radiosurgery.
Topics: Brachytherapy; Dose Fractionation, Radiation; Humans; Male; Prostatic Neoplasms
PubMed: 34164950
DOI: 10.1002/cnr2.1450