scholarly journals RTHP-40. EFFECT OF RIND-BASED DOSIMETRIC TECHNIQUES FOR SCALP DOSE REDUCTION IN BRAIN IRRADIATION

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi218-vi218
Author(s):  
Diana No ◽  
Diana Julie ◽  
Jonathan Knisely
Keyword(s):  
Tumor Volume ◽  
Standard Treatment ◽  
Dose Calculation ◽  
Skin Surface ◽  
Dose Fractionation ◽  
Brain Irradiation ◽  
Unwanted Side Effect ◽  
Dose Limits ◽  
Radiation Induced

Abstract OBJECTIVE Radiation-induced alopecia is an unwanted side effect causing permanent cosmetic distress if hair regrowth does not occur. Rind-based techniques can effectively control dosimetric spread. We evaluated this technique to reduce scalp dose and alopecia while maintaining tumor coverage. METHODS Ten consecutive brain tumor plans were retrospectively evaluated. All planning tumor volume (PTV) margins were ≤ 15.0mm from the skin surface. Departmental guidelines for fractionation were followed, with minimum 95% PTV coverage receiving 100% dose. Fractionation variation was accounted for with biologically effective dose calculation (alpha/beta=2). Rind structures encompassed 5mm depth from scalp surface; upper dose limits were customized to minimum values without PTV coverage compromise. Standard comparative plans using identical criteria, without rind structures, were calculated. Scalp dose evaluation was defined for tissue from skin to 5mm depth. Paired T-tests were used for comparative evaluation. RESULTS Median age: 58 (range 27–85); 70% female (n=7). Histologies included gliomas (n=7) and meningiomas (n=3). Median PTV distance to skin surface: 13.5mm (range 8.0–15.0). Median PTV minimum and mean dose for rind-based plans: 88.63% (range 73.14–95.2) and 104.39% (range 102.07–107.38) of prescription and 90.90% (range 68.64–98.21) and 103.02% (range 101.91–107.04) for standard plans, respectively. Statistically significant reduction in scalp maximum and mean dose of 19.65% (p=2.72E-06) and 0.48% (p=0.007), respectively, was seen with rind-based planning. Scalp volume receiving 1000cGy-equivalent increased 6.7cc using rind-based techniques, although insignificant (p=0.33). Volume receiving 1500cGy-equivalent was significantly reduced 3.88cc (p=0.03) using rind-based techniques. With median 28.5 day follow-up, of 5 patients treated using rind-based techniques, 40% (n=2) exhibited acute alopecia compared to 100% of those treated with standard plans. CONCLUSION Rind-based dosimetric techniques exhibit significant reduction of scalp dose in brain irradiation. 60% of patients treated using this technique experienced no alopecia, versus 0% receiving standard treatment. Further investigation is warranted to better evaluate correlation.

scholarly journals RADI-39. EFFECT OF RIND-BASED DOSIMETRIC TECHNIQUES FOR SCALP DOSE REDUCTION IN BRAIN IRRADIATION

2019 ◽  
Vol 1 (Supplement_1) ◽  
pp. i29-i29
Author(s):  
Diana No ◽  
Diana Julie ◽  
Jonathan Knisely
Keyword(s):  
Tumor Volume ◽  
Standard Treatment ◽  
Dose Calculation ◽  
Skin Surface ◽  
Dose Fractionation ◽  
Brain Irradiation ◽  
Unwanted Side Effect ◽  
Dose Limits ◽  
Radiation Induced

Abstract OBJECTIVE: Radiation-induced alopecia is an unwanted side effect causing permanent cosmetic distress if hair regrowth does not occur. Rind-based techniques can effectively control dosimetric spread. We evaluated this technique to reduce scalp dose and alopecia while maintaining tumor coverage. METHODS: Ten consecutive brain tumor plans were retrospectively evaluated. All planning tumor volume (PTV) margins were ≤ 15.0mm from the skin surface. Departmental guidelines for fractionation were followed, with minimum 95% PTV coverage receiving 100% dose. Fractionation variation was accounted for with biologically effective dose calculation (alpha/beta=2). Rind structures encompassed 5mm depth from scalp surface; upper dose limits were customized to minimum values without PTV coverage compromise. Standard comparative plans using identical criteria, without rind structures, were calculated. Scalp dose evaluation was defined for tissue from skin to 5mm depth. Paired T-tests were used for comparative evaluation. RESULTS: Median age: 58 (range 27–85); 70% female (n=7). Histologies included gliomas (n=7) and meningiomas (n=3). Median PTV distance to skin surface: 13.5mm (range 8.0–15.0). Median PTV minimum and mean dose for rind-based plans: 88.63% (range 73.14–95.2) and 104.39% (range 102.07–107.38) of prescription and 90.90% (range 68.64–98.21) and 103.02% (range 101.91–107.04) for standard plans, respectively. Statistically significant reduction in scalp maximum and mean dose of 19.65% (p=2.72E-06) and 0.48% (p=0.007), respectively, was seen with rind-based planning. Scalp volume receiving 1000cGy-equivalent increased 6.7cc using rind-based techniques, although insignificant (p=0.33). Volume receiving 1500cGy-equivalent was significantly reduced 3.88cc (p=0.03) using rind-based techniques. With median 28.5 day follow-up, of 5 patients treated using rind-based techniques, 40% (n=2) exhibited acute alopecia compared to 100% of those treated with standard plans. CONCLUSION: Rind-based dosimetric techniques exhibit significant reduction of scalp dose in brain irradiation. 60% of patients treated using this technique experienced no alopecia, versus 0% receiving standard treatment. Further investigation is warranted to better evaluate correlation.

Gamma knife surgery for vestibular schwannoma: 10-year experience of 195 cases

2005 ◽  
Vol 102 (Special_Supplement) ◽  
pp. 87-97 ◽  
Author(s):  
Wen-Yuh Chung ◽  
Kang-Du Liu ◽  
Cheng-Ying Shiau ◽  
Hsiu-Mei Wu ◽  
Ling-Wei Wang ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Gamma Knife ◽  
Vestibular Schwannoma ◽  
Tumor Volume ◽  
Radiation Effect ◽  
Gamma Knife Surgery ◽  
Homogeneous Distribution ◽  
Content Type ◽  
Fine Print

Object. The authors conducted a study to determine the optimal radiation dose for vestibular schwannoma (VS) and to examine the histopathology in cases of treatment failure for better understanding of the effects of irradiation. Methods. A retrospective study was performed of 195 patients with VS; there were 113 female and 82 male patients whose mean age was 51 years (range 11–82 years). Seventy-two patients (37%) had undergone partial or total excision of their tumor prior to gamma knife surgery (GKS). The mean tumor volume was 4.1 cm3 (range 0.04–23.1 cm3). Multiisocenter dose planning placed a prescription dose of 11 to 18.2 Gy on the 50 to 94% isodose located at the tumor margin. Clinical and magnetic resonance (MR) imaging follow-up evaluations were performed every 6 months. A loss of central enhancement was demonstrated on MR imaging in 69.5% of the patients. At the latest MR imaging assessment decreased or stable tumor volume was demonstrated in 93.6% of the patients. During a median follow-up period of 31 months resection was avoided in 96.8% of cases. Uncontrolled tumor swelling was noted in five patients at 3.5, 17, 24, 33, and 62 months after GKS, respectively. Twelve of 20 patients retained serviceable hearing. Two patients experienced a temporary facial palsy. Two patients developed a new trigeminal neuralgia. There was no treatment-related death. Histopathological examination of specimens in three cases (one at 62 months after GKS) revealed a long-lasting radiation effect on vessels inside the tumor. Conclusions. Radiosurgery had a long-term radiation effect on VSs for up to 5 years. A margin 12-Gy dose with homogeneous distribution is effective in preventing tumor progression, while posing no serious threat to normal cranial nerve function.

scholarly journals Biologically effective dose correlates with linear tumor volume changes after upfront single-fraction stereotactic radiosurgery for vestibular schwannomas

2021 ◽  
Author(s):  
Constantin Tuleasca ◽  
Mohamed Faouzi ◽  
Philippe Maeder ◽  
Raphael Maire ◽  
Jonathan Knisely ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Effective Dose ◽  
Stereotactic Radiosurgery ◽  
Tumor Volume ◽  
Vestibular Schwannomas ◽  
Benign Tumors ◽  
Biologically Effective Dose ◽  
Volume Changes ◽  
Single Fraction

AbstractVestibular schwannomas (VSs) are benign, slow-growing tumors. Management options include observation, surgery, and radiation. In this retrospective trial, we aimed at evaluating whether biologically effective dose (BED) plays a role in tumor volume changes after single-fraction first intention stereotactic radiosurgery (SRS) for VS. We compiled a single-institution experience (n = 159, Lausanne University Hospital, Switzerland). The indication for SRS was decided after multidisciplinary discussion. Only cases with minimum 3 years follow-up were included. The Koos grading, a reliable method for tumor classification was used. Radiosurgery was performed using Gamma Knife (GK) and a uniform marginal prescription dose of 12 Gy. Mean BED was 66.3 Gy (standard deviation 3.8, range 54.1–73.9). The mean follow-up period was 5.1 years (standard deviation 1.7, range 3–9.2). The primary outcome was changes in 3D volumes after SRS as function of BED and of integral dose received by the VS. Random-effect linear regression model showed that tumor volume significantly and linearly decreased over time with higher BED (p < 0.0001). Changes in tumor volume were also significantly associated with age, sex, number of isocenters, gradient index, and Koos grade. However, the effect of BED on tumor volume change was moderated by time after SRS and Koos grade. Lower integral doses received by the VSs were inversely correlated with BED in relationship with tumor volume changes (p < 0.0001). Six (3.4%) patients needed further intervention. For patients having uniformly received the same marginal dose prescription, higher BED linearly and significantly correlated with tumor volume changes after SRS for VSs. BED could represent a potential new treatment paradigm for patients with benign tumors, such as VSs, for attaining a desired radiobiological effect. This could further increase the efficacy and decrease the toxicity of SRS not only in benign tumors but also in other SRS indications.

scholarly journals Natural history and treatment options of radiation-induced brain cavernomas: a systematic review

2021 ◽  
Author(s):  
Gildas Patet ◽  
Andrea Bartoli ◽  
Torstein R. Meling
Keyword(s):  
Systematic Review ◽  
Natural History ◽  
Radiation Treatment ◽  
Neurological Deficits ◽  
Cochrane Library ◽  
Average Dose ◽  
Cavernous Malformations ◽  
Radiation Induced ◽  
The Mean

AbstractRadiation-induced cavernous malformations (RICMs) are delayed complications of brain irradiation during childhood. Its natural history is largely unknown and its incidence may be underestimated as RCIMS tend to develop several years following radiation. No clear consensus exists regarding the long-term follow-up or treatment. A systematic review of Embase, Cochrane Library, PubMed, Google Scholar, and Web of Science databases, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, was performed. Based on our inclusion/exclusion criteria, 12 articles were included, totaling 113 children with RICMs, 86 were treated conservatively, and 27 with microsurgery. We were unable to precisely define the incidence and natural history from this data. The mean age at radiation treatment was 7.3 years, with a slight male predominance (54%) and an average dose of 50.0 Gy. The mean time to detection of RICM was 9.2 years after radiation. RICM often developed at distance from the primary lesion, more specifically frontal (35%) and temporal lobe (34%). On average, 2.6 RICMs were discovered per child. Sixty-seven percent were asymptomatic. Twenty-one percent presented signs of hemorrhage. Clinical outcome was favorable in all children except in 2. Follow-up data were lacking in most of the studies. RICM is most often asymptomatic but probably an underestimated complication of cerebral irradiation in the pediatric population. Based on the radiological development of RICMs, many authors suggest a follow-up of at least 15 years. Studies suggest observation for asymptomatic lesions, while surgery is reserved for symptomatic growth, hemorrhage, or focal neurological deficits.

scholarly journals RONC-19. TWO CASES OF RE-IRRADIATION FOR LATE RECURRENT OR RADIATION-INDUCED TUMOR AFTER RADIATION THERAPY FOR PEDIATRIC BRAIN TUMORS

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii459-iii459
Author(s):  
Takashi Mori ◽  
Shigeru Yamaguchi ◽  
Rikiya Onimaru ◽  
Takayuki Hashimoto ◽  
Hidefumi Aoyama
Keyword(s):  
Radiation Therapy ◽  
Brain Tumors ◽  
Tumor Resection ◽  
Intensity Modulated Radiation Therapy ◽  
Late Recurrence ◽  
Pediatric Brain Tumors ◽  
Suprasellar Region ◽  
Radiation Induced ◽  
Pediatric Brain

Abstract BACKGROUND As the outcome of pediatric brain tumors improves, late recurrence and radiation-induced tumor cases are more likely to occur, and the number of cases requiring re-irradiation is expected to increase. Here we report two cases performed intracranial re-irradiation after radiotherapy for pediatric brain tumors. CASE 1: 21-year-old male. He was diagnosed with craniopharyngioma at eight years old and underwent a tumor resection. At 10 years old, the local recurrence of suprasellar region was treated with 50.4 Gy/28 fr of stereotactic radiotherapy (SRT). After that, other recurrent lesions appeared in the left cerebellopontine angle, and he received surgery three times. The tumor was gross totally resected and re-irradiation with 40 Gy/20 fr of SRT was performed. We have found no recurrence or late effects during the one year follow-up. CASE 2: 15-year-old female. At three years old, she received 18 Gy/10 fr of craniospinal irradiation and 36 Gy/20 fr of boost to the posterior fossa as postoperative irradiation for anaplastic ependymoma and cured. However, a anaplastic meningioma appeared on the left side of the skull base at the age of 15, and 50 Gy/25 fr of postoperative intensity-modulated radiation therapy was performed. Two years later, another meningioma developed in the right cerebellar tent, and 54 Gy/27 fr of SRT was performed. Thirty-three months after re-irradiation, MRI showed a slight increase of the lesion, but no late toxicities are observed. CONCLUSION The follow-up periods are short, however intracranial re-irradiation after radiotherapy for pediatric brain tumors were feasible and effective.

A review on radiation induced nausea and vomiting: “Current management strategies and prominence of radio sensitizers”

2021 ◽  
pp. 107815522110115
Author(s):  
Meenu Vijayan ◽  
Sherin Joseph ◽  
Emmanuel James ◽  
Debnarayan Dutta
Keyword(s):  
Radiation Therapy ◽  
Cell Damage ◽  
Genetic Material ◽  
High Energy ◽  
Concurrent Chemotherapy ◽  
Nausea And Vomiting ◽  
Dose Fractionation ◽  
Psychological State ◽  
Related Factors ◽  
Radiation Induced

Radiations dissipated are high energy waves used mostly as treatment intervention in controlling the unwanted multiplication of cell. About 60%–65% of cancer treatment requires radiation therapy and 40%–80% of radiation therapy causes RINV which are true troublemakers. Radiation therapy (RT) is targeted therapy mostly used to treat early stages of tumour and prevent their reoccurrence. They mainly destroy the genetic material (DNA) of cancerous cells to avoid their unwanted growth and division. The RINV affects the management and quality of life of patients which further reduces the patient outcome. RINV depends on RT related factors (dose, fractionation, irradiation volume, RT techniques) and patient related factors like (gender, health conditions, age, concurrent chemotherapy, psychological state, and tumour stage). RT is an active area of research and there is only limited progress in tackling the RINV crisis. Advanced technological methods are adopted that led to better understanding of total lethal doses. Radiation therapy also affects the immunity system that leads to radiation induced immune responses and inflammation. Radio sensitizers are used to sensitize the tumour cells to radiations that further prevent the normal cell damage from radiation exposure. There is a need for future studies and researches to re-evaluate the data available from previous trials in RINV to make better effective antiemetic regimen. The article focuses on radiation therapy induced nausea and vomiting along with their mechanism of action and treatment strategies in order to have a remarkable patient care.

scholarly journals Cumulative incidence and risk factors for radiation induced leukoencephalopathy in high grade glioma long term survivors

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Robert Terziev ◽  
Dimitri Psimaras ◽  
Yannick Marie ◽  
Loic Feuvret ◽  
Giulia Berzero ◽  
...  
Keyword(s):  
Risk Factors ◽  
Cumulative Incidence ◽  
High Grade Glioma ◽  
High Grade ◽  
Nucleotide Polymorphisms ◽  
Increased Risk ◽  
Radiation Induced ◽  
Long Term Survivors

AbstractThe incidence and risk factors associated with radiation-induced leukoencephalopathy (RIL) in long-term survivors of high-grade glioma (HGG) are still poorly investigated. We performed a retrospective research in our institutional database for patients with supratentorial HGG treated with focal radiotherapy, having a progression-free overall survival > 30 months and available germline DNA. We reviewed MRI scans for signs of leukoencephalopathy on T2/FLAIR sequences, and medical records for information on cerebrovascular risk factors and neurological symptoms. We investigated a panel of candidate single nucleotide polymorphisms (SNPs) to assess genetic risk. Eighty-one HGG patients (18 grade IV and 63 grade III, 50M/31F) were included in the study. The median age at the time of radiotherapy was 48 years old (range 18–69). The median follow-up after the completion of radiotherapy was 79 months. A total of 44 patients (44/81, 54.3%) developed RIL during follow-up. Twenty-nine of the 44 patients developed consistent symptoms such as subcortical dementia (n = 28), gait disturbances (n = 12), and urinary incontinence (n = 9). The cumulative incidence of RIL was 21% at 12 months, 42% at 36 months, and 48% at 60 months. Age > 60 years, smoking, and the germline SNP rs2120825 (PPARg locus) were associated with an increased risk of RIL. Our study identified potential risk factors for the development of RIL (age, smoking, and the germline SNP rs2120825) and established the rationale for testing PPARg agonists in the prevention and management of late-delayed radiation-induced neurotoxicity.

scholarly journals Short diameter may be a useful simple indicator of the tumor response in skull base meningiomas after conventionally fractionated stereotactic radiotherapy

2021 ◽  
Author(s):  
Keiichi Takehana ◽  
Daisuke Nakamura ◽  
Alshaymaa Abdelghaffar ◽  
Megumi Uto ◽  
Tomohiro Katagiri ◽  
...  
Keyword(s):  
Skull Base ◽  
Stereotactic Radiotherapy ◽  
Tumor Volume ◽  
Tumor Response ◽  
Fractionated Stereotactic Radiotherapy ◽  
Skull Base Meningioma ◽  
Skull Base Meningiomas ◽  
Simple Indicator ◽  
Conventionally Fractionated

Abstract Objectives The purpose of this study was to assess the radiological change patterns in skull base meningiomas after conventionally fractionated stereotactic radiotherapy (CFSRT) to determine a simple and valid method to assess the tumor response. Materials and methods Forty-one patients with a benign skull base meningioma treated by CFSRT from March 2007 to August 2015 were retrospectively evaluated. We measured tumor volume (TV), long-axis diameter (LD), and short-axis diameter (SD) on both pre-treatment images and follow-up images of 1, 3, and 5 years after CFSRT, respectively. The paired t test was used to detect differences in the LD and SD change rates. Spearman’s correlation coefficients were calculated to evaluate relationships between the TV and the diameters changes. Results The number of available follow-up MRIs that was performed at 1, 3, and 5 years after the CFSRT was 41 (100%), 34 (83%), and 23 (56%), respectively. The change rates of SD were significantly higher than those of LD at every time point and more strongly correlated with the change rates of tumor volume at 3 and 5 years after CFSRT. Conclusions SD may be useful as a simple indicator of the tumor response for skull base meningioma after CFSRT. Key Points • The change rate in short-axis diameter is a useful and simple indicator of the response of skull base meningioma to conventionally fractionated stereotactic radiotherapy. • Conventionally fractionated stereotactic radiotherapy for skull base meningioma achieved excellent 5-year local control.

scholarly journals Impact of [18F]FDG-PET and [18F]FLT-PET-Parameters in Patients with Suspected Relapse of Irradiated Lung Cancer

Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 279
Author(s):  
Tine N. Christensen ◽  
Seppo W. Langer ◽  
Gitte Persson ◽  
Klaus Richter Larsen ◽  
Annemarie G. Amtoft ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Overall Survival ◽  
Fdg Pet ◽  
Tumor Volume ◽  
High Dose ◽  
Flt Pet ◽  
Pet Ct ◽  
Radiation Induced ◽  
Fdg Pet Ct ◽  
Induced Changes

Radiation-induced changes may cause a non-malignant high 2-deoxy-2-[18F]fluoro-d-glucose (FDG)-uptake. The 3′-deoxy-3′-[18F]fluorothymidine (FLT)-PET/CT performs better in the differential diagnosis of inflammatory changes and lung lesions with a higher specificity than FDG-PET/CT. We investigated the association between post-radiotherapy FDG-PET-parameters, FLT-PET-parameters, and outcome. Sixty-one patients suspected for having a relapse after definitive radiotherapy for lung cancer were included. All the patients had FDG-PET/CT and FLT-PET/CT. FDG-PET- and FLT-PET-parameters were collected from within the irradiated high-dose volume (HDV) and from recurrent pulmonary lesions. For associations between PET-parameters and relapse status, respectively, the overall survival was analyzed. Thirty patients had a relapse, of these, 16 patients had a relapse within the HDV. FDG-SUVmax and FLT-SUVmax were higher in relapsed HDVs compared with non-relapsed HDVs (median FDG-SUVmax: 12.8 vs. 4.2; p < 0.001; median FLT-SUVmax 3.9 vs. 2.2; p < 0.001). A relapse within HDV had higher FDG-SUVpeak (median FDG-SUVpeak: 7.1 vs. 3.5; p = 0.014) and was larger (median metabolic tumor volume (MTV50%): 2.5 vs. 0.7; 0.014) than the relapsed lesions outside of HDV. The proliferative tumor volume (PTV50%) was prognostic for the overall survival (hazard ratio: 1.07 pr cm3 [1.01–1.13]; p = 0.014) in the univariate analysis, but not in the multivariate analysis. FDG-SUVmax and FLT-SUVmax may be helpful tools for differentiating the relapse from radiation-induced changes, however, they should not be used definitively for relapse detection.

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