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International Journal of Radiation... Jun 2024Few reports describe the risks of late ocular toxicities after radiation therapy (RT) for childhood cancers despite their effect on quality of life. The Pediatric Normal... (Review)
Review
PURPOSE
Few reports describe the risks of late ocular toxicities after radiation therapy (RT) for childhood cancers despite their effect on quality of life. The Pediatric Normal Tissue Effects in the Clinic (PENTEC) ocular task force aims to quantify the radiation dose dependence of select late ocular adverse effects. Here, we report results concerning retinopathy, optic neuropathy, and cataract in childhood cancer survivors who received cranial RT.
METHODS AND MATERIALS
A systematic literature search was performed using the PubMed, MEDLINE, and Cochrane Library databases for peer-reviewed studies published from 1980 to 2021 related to childhood cancer, RT, and ocular endpoints including dry eye, keratitis/corneal injury, conjunctival injury, cataract, retinopathy, and optic neuropathy. This initial search yielded abstracts for 2947 references, 269 of which were selected as potentially having useful outcomes and RT data. Data permitting, treatment and outcome data were used to generate normal tissue complication probability models.
RESULTS
We identified sufficient RT data to generate normal tissue complication probability models for 3 endpoints: retinopathy, optic neuropathy, and cataract formation. Based on limited data, the model for development of retinopathy suggests 5% and 50% risk of toxicity at 42 and 62 Gy, respectively. The model for development of optic neuropathy suggests 5% and 50% risk of toxicity at 57 and 64 Gy, respectively. More extensive data were available to evaluate the risk of cataract, separated into self-reported versus ophthalmologist-diagnosed cataract. The models suggest 5% and 50% risk of self-reported cataract at 12 and >40 Gy, respectively, and 50% risk of ophthalmologist-diagnosed cataract at 9 Gy (>5% long-term risk at 0 Gy in patients treated with chemotherapy only).
CONCLUSIONS
Radiation dose effects in the eye are inadequately studied in the pediatric population. Based on limited published data, this PENTEC comprehensive review establishes relationships between RT dose and subsequent risks of retinopathy, optic neuropathy, and cataract formation.
Topics: Humans; Cataract; Cancer Survivors; Retinal Diseases; Child; Optic Nerve Diseases; Radiation Injuries; Radiotherapy Dosage; Organs at Risk; Cranial Irradiation
PubMed: 37565958
DOI: 10.1016/j.ijrobp.2023.06.007 -
Radiotherapy and Oncology : Journal of... May 2024Stereotactic ablative radiation therapy (SBRT) is an emerging treatment option for primary renal cell carcinoma (RCC), particularly in patients who are unsuitable for... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Stereotactic ablative radiation therapy (SBRT) is an emerging treatment option for primary renal cell carcinoma (RCC), particularly in patients who are unsuitable for surgery. The aim of this review is to assess the effect of increasing the biologically equivalent dose (BED) via various radiation fractionation regimens on clinical outcomes.
METHODS
A literature search was conducted in PubMed (Medline), EMBASE, and the Cochrane Library for studies published up to October 2023. Studies reporting on patients with localized RCC receiving SBRT were included to determine its effectiveness on local control, progression-free survival, and overall survival. A random effects model was used to meta-regress clinical outcomes relative to the BED for each study and heterogeneity was assessed by I.
RESULTS
A total of 724 patients with RCC from 22 studies were included, with a mean age of 72.7 years (range: 44.0-81.0). Local control was excellent with an estimate of 99 % (95 %CI: 97-100 %, I = 19 %), 98 % (95 %CI: 96-99 %, I = 8 %), and 94 % (95 %CI: 90-97 %, I = 11 %) at one year, two years, and five years respectively. No definitive association between increasing BED and local control, progression-free survival and overall survival was observed. No publication bias was observed.
CONCLUSIONS
A significant dose response relationship between oncological outcomes and was not identified, and excellent local control outcomes were observed at the full range of doses. Until new evidence points otherwise, we support current recommendations against routine dose escalation beyond 25-26 Gy in one fraction or 42-48 Gy in three fractions, and to consider de-escalation or compromising target coverage if required to achieve safe organ at risk doses.
Topics: Humans; Carcinoma, Renal Cell; Dose Fractionation, Radiation; Dose-Response Relationship, Radiation; Kidney Neoplasms; Treatment Outcome
PubMed: 38462092
DOI: 10.1016/j.radonc.2024.110216 -
European Journal of Surgical Oncology :... Jan 2024(Chemo)radiation may be a required treatment in young women with pelvic malignancies. Irradiation may result in ovarian and uterine failure, compromising the fertility... (Review)
Review
Uterine transposition versus uterine ventrofixation before radiotherapy as a fertility sparing option in young women with pelvic malignancies: Systematic review of the literature and dose simulation.
BACKGROUND
(Chemo)radiation may be a required treatment in young women with pelvic malignancies. Irradiation may result in ovarian and uterine failure, compromising the fertility of those patients. While ovarian transposition is an established method to move the ovaries away from the irradiation field, similar surgical procedures regarding the uterus remain investigational. The aim of this study was to carry out a systematic review of the literature on uterine displacement techniques (ventrofixation/transposition) and to simulate the radiation dose received by the uterus in different heights place after the procedures.
METHODS
The systematic review was performed according PRISMA guidelines. PubMed, Scopus, Web of Science and EMBASE were queried to identify included study until March 2023. Retrospectively, a dosimetric study was also performed and Volumetric Modulated Arc Therapy (VMAT) radiotherapy treatment plans were calculated, to assess the dose received by the uterus according to hypothetical different displacement positions taking the case of irradiation for rectal or anal cancer as model.
RESULTS
A total of 187 studies were included, after the screening 9 studies were selected for synthesis. Data from the dose simulation revealed that the transposition approach was the most protective with a maximum dose of about 3 and 8 Gy for anal and rectal cancer respectively. None of the simulated ventrofixation positions received a Dmean surpassing 14 Gy.
CONCLUSION
According to the literature review and the simulation results of the present study we may conclude are feasible and safe as fertility sparing approach in young rectal/anal cancer patients.
Topics: Humans; Female; Pelvic Neoplasms; Retrospective Studies; Uterus; Organ Sparing Treatments; Radiotherapy, Intensity-Modulated; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted; Anus Neoplasms
PubMed: 37992415
DOI: 10.1016/j.ejso.2023.107270 -
Health Physics Mar 2024A comprehensive search was performed to examine the literature on diagnostic reference levels (DRL) for computed tomography (CT) and radiography examinations that are...
A comprehensive search was performed to examine the literature on diagnostic reference levels (DRL) for computed tomography (CT) and radiography examinations that are performed routinely in Jordan. EBSCO, Scopus, and Web of Science were used for the search. The acronym "DRL" and the additional phrase "dose reference levels" were used to search for articles in literature. Seven papers that reported DRL values for radiography and CT scans in Jordan were identified. One study reported DRLs for conventional radiography, two studies reported CT DRLs in pediatrics, and the remaining four studies provided DRL values for adult CT scans. The most popular techniques for determining the DRLs were the entrance surface dose, volume CT dose index (CTDIvol), and dose-length product (DLP) values. Variations in Jordanian DRL values were noted across both modalities. Lower radiation doses and less variation in DRL values may be achieved by educating and training radiographers to better understand dose reduction strategies. To limit dose variance and enable dosage comparison, CT DRLs must be standardized in accordance with the guidelines of the International Commission on Radiological Protection (ICRP).
Topics: Adult; Child; Humans; Jordan; Diagnostic Reference Levels; Tomography, X-Ray Computed; Radiation Protection
PubMed: 38252949
DOI: 10.1097/HP.0000000000001778 -
International Journal of Radiation... Jun 2024A Pediatric Normal Tissue Effects in the Clinic (PENTEC) analysis of published investigations of central nervous system (CNS) subsequent neoplasms (SNs), subsequent...
PURPOSE
A Pediatric Normal Tissue Effects in the Clinic (PENTEC) analysis of published investigations of central nervous system (CNS) subsequent neoplasms (SNs), subsequent sarcomas, and subsequent lung cancers in childhood cancer survivors who received radiation therapy (RT) was performed to estimate the effect of RT dose on the risk of SNs and the modification of this risk by host and treatment factors.
METHODS AND MATERIALS
A systematic literature review was performed to identify data published from 1975 to 2022 on SNs after prior RT in childhood cancer survivors. After abstract review, usable quantitative and qualitative data were extracted from 83 studies for CNS SNs, 118 for subsequent sarcomas, and 10 for lung SNs with 4 additional studies (3 for CNS SNs and 1 for lung SNs) later added. The incidences of SNs, RT dose, age, sex, primary cancer diagnosis, chemotherapy exposure, and latent time from primary diagnosis to SNs were extracted to assess the factors influencing risk for SNs. The excess relative ratio (ERR) for developing SNs as a function of dose was analyzed using inverse-variance weighted linear regression, and the ERR/Gy was estimated. Excess absolute risks were also calculated.
RESULTS
The ERR/Gy for subsequent meningiomas was estimated at 0.44 (95% CI, 0.19-0.68); for malignant CNS neoplasms, 0.15 (95% CI, 0.11-0.18); for sarcomas, 0.045 (95% CI, 0.023-0.067); and for lung cancer, 0.068 (95% CI, 0.03-0.11). Younger age at time of primary diagnosis was associated with higher risk of subsequent meningioma and sarcoma, whereas no significant effect was observed for age at exposure for risk of malignant CNS neoplasm, and insufficient data were available regarding age for lung cancer. Females had a higher risk of subsequent meningioma (odds ratio, 1.46; 95% CI, 1.22-1.76; P < .0001) relative to males, whereas no statistically significant sex difference was seen in risk of malignant CNS neoplasms, sarcoma SNs, or lung SNs. There was an association between chemotherapy receipt (specifically alkylating agents and anthracyclines) and subsequent sarcoma risk, whereas there was no clear association between specific chemotherapeutic agents and risk of CNS SNs and lung SNs.
CONCLUSIONS
This PENTEC systematic review shows a significant radiation dose-response relationship for CNS SNs, sarcomas, and lung SNs. Given the linear dose response, improved conformality around the target volume that limits the high dose volume might be a promising strategy for reducing the risk of SNs after RT. Other host- and treatment-related factors such as age and chemotherapy play a significant contributory role in the development of SNs and should be considered when estimating the risk of SNs after RT among childhood cancer survivors.
Topics: Humans; Child; Cancer Survivors; Neoplasms, Second Primary; Neoplasms, Radiation-Induced; Sarcoma; Lung Neoplasms; Female; Male; Central Nervous System Neoplasms; Adolescent; Child, Preschool; Meningioma; Radiotherapy Dosage; Infant; Age Factors; Young Adult
PubMed: 37777927
DOI: 10.1016/j.ijrobp.2023.07.025 -
International Journal of Radiation... Jun 2024The Pediatric Normal Tissue Effects in the Clinic (PENTEC) hearing loss (HL) task force reviewed investigations on cochlear radiation dose-response relationships and...
PURPOSE
The Pediatric Normal Tissue Effects in the Clinic (PENTEC) hearing loss (HL) task force reviewed investigations on cochlear radiation dose-response relationships and risk factors for developing HL. Evidence-based dose-response data are quantified to guide treatment planning.
METHODS AND MATERIALS
A systematic review of the literature was performed to correlate HL with cochlear dosimetry. HL was considered present if a threshold exceeded 20 dB at any frequency. Radiation dose, ototoxic chemotherapy exposure, hearing profile including frequency spectra, interval to HL, and age at radiation therapy (RT) were analyzed.
RESULTS
Literature was systematically reviewed from 1970 to 2021. This resulted in 739 abstracts; 19 met inclusion for meta-analysis, and 4 included data amenable to statistical modeling. These 4 studies included 457 cochleas at risk in patients treated with RT without chemotherapy, and 398 cochlea treated with chemotherapy. The incidence and severity of cochlear HL from RT exposure alone is related to dose and age. Risk of HL was <5% in cochlea receiving a mean dose ≤35 Gy but increased to 30% at 50 Gy. HL risk ranged from 25% to 40% in children under the age of 5 years at diagnosis, declining to 10% in older children for any radiation dose. Probability of similar severe HL occurred at doses 18.3 Gy higher for children <3 versus >3 years of age. High-frequency HL was most common, with average onset occurring 3.6 years (range, 0.4-13.2 years) after RT. Exposure to platinum-based chemotherapies added to the rates of HL at a given cochlear dose level, with 300 mg/m shifting the dose response by 7 Gy.
CONCLUSIONS
In children treated with RT alone, risk of HL was low for cochlear dose <35 Gy and rose when dose exceeded 35 Gy without clear RT dose dependence. High-frequency HL was most prevalent, but all frequencies were affected. Children younger than 5 years were at highest risk of developing HL, although independent effects of dose and age were not fully elucidated. Future reports with more granular data are needed to better delineate time to onset of HL and the effects of chemoradiotherapy.
Topics: Humans; Hearing Loss; Child; Cochlea; Cancer Survivors; Child, Preschool; Dose-Response Relationship, Radiation; Adolescent; Age Factors; Risk Factors; Infant; Radiotherapy; Radiotherapy Dosage; Organs at Risk
PubMed: 37855793
DOI: 10.1016/j.ijrobp.2023.08.016 -
AIDS and Behavior Jul 2024Vaccine hesitancy is one of the top 10 threats to global health, which affects the prevalence and fatality of vaccine-preventable diseases over the world. During the... (Meta-Analysis)
Meta-Analysis
Vaccine hesitancy is one of the top 10 threats to global health, which affects the prevalence and fatality of vaccine-preventable diseases over the world. During the COVID-19 pandemic, people living with HIV (PLWH) may have higher risks of infection, more serious complications, and worse prognosis without the protection of the COVID-19 vaccine. A systematic review and meta-analysis aiming to evaluate the prevalence of COVID-19 vaccine hesitancy among PLWH was conducted using PubMed, Embase, and Web of Science databases for studies published between January 1, 2020, and August 31, 2022. The pooled prevalence with a corresponding 95%CI of COVID-19 vaccine hesitancy among PLWH was reported. Subgroup analysis was conducted to explore variation in prevalence across different categories. 23 studies with a total of 19,922 PLWH were included in this study. The prevalence of COVID-19 vaccine hesitancy among PLWH was 34.0%, and the influencing factors included male, influenza vaccination experience, and a CD4 count of more than 200 cells/mm. Subgroup analysis did not identify significant causes of heterogeneity but showed that the prevalence of COVID-19 vaccine hesitancy among PLWH varies by study period, region, and race. Although all PLWH are recommended to receive the COVID-19 vaccine, a large proportion of them remain hesitant to be vaccinated. Therefore, governments and relevant institutions should take specific measures to encourage and promote vaccination to improve the coverage of the COVID-19 vaccine among PLWH.
Topics: Female; Humans; Male; COVID-19; COVID-19 Vaccines; HIV Infections; SARS-CoV-2; Vaccination; Vaccination Hesitancy
PubMed: 38625625
DOI: 10.1007/s10461-024-04344-9 -
Radiation Oncology (London, England) Jan 2024SBRT is an effective local treatment for patients with early-stage non-small cell lung cancer (NSCLC). This treatment is currently used in patients who have poor lung... (Review)
Review
SBRT is an effective local treatment for patients with early-stage non-small cell lung cancer (NSCLC). This treatment is currently used in patients who have poor lung function or who decline surgery. As SBRT usually has small PTV margins, reducing the beam-on-time (BOT) is beneficial for accurate dose delivery by minimising intrafraction motion as well as improved patient comfort. Removal of the linear accelerator flattening filter can provide a higher dose rate which results in a faster treatment. In addition, the choice of photon energy can also affect the dose distribution to the target and the organs-at-risk (OAR). In this systematic review, studies analysing the choice of various photon beam energies, with a flattening filter or flattening filter free (FFF), were compared for their overall dosimetric benefit in the SBRT treatment for early-stage NSCLC. It was found that FFF treatment delivers a comparatively more conformal dose distribution, as well as a better homogeneity index and conformity index, and typically reduces BOT by between 30 and 50%. The trade-off may be a minor increase in monitor units for FFF treatment found in some studies but not others. Target conformity and OAR sparing, particularly lung doses appear better with 6MV FFF, but 10MV FFF was marginally more advantageous for skin sparing and BOT reduction. The favourable beam modality for clinical use would depend on the individual case, for which tumour size and depth, radiotherapy technique, as well as fractionation scheme need to be taken into account.
Topics: Humans; Radiosurgery; Carcinoma, Non-Small-Cell Lung; Lung Neoplasms; Radiotherapy, Intensity-Modulated; Radiotherapy Planning, Computer-Assisted; Lung; Small Cell Lung Carcinoma; Radiotherapy Dosage
PubMed: 38167095
DOI: 10.1186/s13014-023-02392-4 -
Dento Maxillo Facial Radiology Apr 2024The aim of this systematic review was to verify the accuracy of linear measurements performed on low-dose CBCT protocols for implant planning, in comparison with those... (Meta-Analysis)
Meta-Analysis
OBJECTIVES
The aim of this systematic review was to verify the accuracy of linear measurements performed on low-dose CBCT protocols for implant planning, in comparison with those performed on standard and high-resolution CBCT protocols.
METHODS
The literature search included four databases (Pubmed, Web of Science, Embase, and Scopus). Two reviewers independently screened titles/abstracts and full texts according to eligibility criteria, extracted the data, and examined the methodological quality. Risk of bias assessment was performed using the Quality Assessment Tool For In Vitro Studies. Random-effects meta-analysis was used for pooling measurement error data.
RESULTS
The initial search yielded 4684 titles. In total, 13 studies were included in the systematic review, representing a total of 81 samples, while 9 studies were included in the meta-analysis. The risk of bias ranged from medium to low. The main results across the studies indicate a strong consistency in linear measurements performed on low-dose images in relation to the reference methods. The overall pooled planning measurement error from low-dose CBCT protocols was -0.24 mm (95% CI, -0.52 to 0.04) with a high level of heterogeneity, showing a tendency for underestimation of real values. Various studies found no significant differences in measurements across different protocols (eg, voxel sizes, mA settings, or dose levels), regions (incisor, premolar, molar) and types (height vs. width). Some studies, however, noted exceptions in measurements performed on the posterior mandible.
CONCLUSION
Low-dose CBCT protocols offer adequate precision and accuracy of linear measurements for implant planning. Nevertheless, diagnostic image quality needs must be taken into consideration when choosing a low-dose CBCT protocol.
Topics: Cone-Beam Computed Tomography; Humans; Radiation Dosage; Patient Care Planning; Dental Implantation, Endosseous; Dental Implants
PubMed: 38429951
DOI: 10.1093/dmfr/twae007