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Barry S Rosenstein

Publications and source records attributed to Barry S Rosenstein.

16 recordsLinked to original sources

Early and late CTCAE and patient-reported outcomes following lung cancer radiotherapy: A sex-stratified descriptive analysis from the REQUITE cohort.

BACKGROUND: Long-term prospective data on lung cancer patients treated with radiotherapy are limited, restricting understanding of outcomes and sex-specific characteristics. The multicentre REQUITE study provides standardized follow-up data from an international cohort. METHODS: We analysed longitudinal data from 530 lung cancer patients treated with radical radiotherapy (sequential or concurrent chemoradiotherapy, or stereotactic body radiation therapy [SBRT]) between 2014 and 2017 at 16 centres in Europe and the USA. Healthcare professionals prospectively recorded 21 pulmonary, oesophageal, neurological, cardiac, and skin adverse events using CTCAE v4.0. Patient-reported outcomes assessed symptoms, quality-of-life, fatigue, and physical activity. Adverse event incidence was stratified by sex, radiotherapy technique, chemotherapy administration, smoking status, and other clinical factors. RESULTS: At 12 months, 309 patients were evaluable, with 151 having follow-up beyond one year. Pulmonary adverse events were most frequent (40% grade ≥ 2), mainly dyspnoea and cough. Women had higher rates of oesophagitis, and more frequently reported dysphagia, and chest wall pain, while men experienced a higher frequency of cardiac adverse events. Exploratory subgroup analyses identified significant sex-related differences in grade ≥ 3 pulmonary adverse events following SBRT and in overall grade ≥ 2 oesophageal adverse events among patients with clinical stage I-II and those aged >70 years. Patient-reported outcomes showed persistent fatigue and reduced physical activity, particularly in females. Symptom prevalence and severity varied by sex, age, treatment modality, smoking status, and clinical stage. CONCLUSION: The REQUITE-Lung cohort provides prospectively collected real-world data on radiotherapy-related adverse events in lung cancer patients. This study describes patterns of adverse events and patient-reported outcomes according to sex, age, and treatment characteristics. These findings are hypothesis-generating and may support future validation in independent and pooled datasets.

Patient-reported outcomes↗

Technical note: reconstructing dose distributions from manually planned electron boosts in breast radiotherapy.

PURPOSE: In breast radiotherapy, delivery of manually-calculated electron boosts limits retrospective dose-response analyses as dose distribution is unavailable. This work evaluates the feasibility of reconstructing dose distributions from manually planned electron boosts in breast-conserving radiotherapy. METHODS: Only 72 out of 198 breast cancer patients had complete stored dose distributions from sequential electron boosts in the REQUITE study. Arbitrary data from 70/72 patients were used to develop and validate dose reconstruction method. Twenty patients were used to determine optimal parameters for Monte-Carlo-based (MC) electron dose reconstruction on RayStation (v.11B-R), considering CT-calibration curve, MC-history number, andcalculation grid resolution. Remaining 50 patients were used to quantify dose reconstruction accuracy. The similarity between reconstructed and stored dose was evaluated using 3D-gamma index and dosimetric parameters extracted from breast and tumour bed contours. Dose difference location was evaluated using dose-location histogram. RESULTS: Calculation grid resolution significantly impacted electron dose distribution (p&#xa0;<&#xa0;0.01), where the finest grid (0.15&#xa0;cm) showed highest similarity to stored doses. CT-calibration curve and MC-history number had a negligible influence on dose reconstruction. Dosimetric difference between reconstructed and stored doses was&#xa0;<&#xa0;1&#xa0;Gy for breast and tumour bed. Reconstructed dose was achieved&#xa0;>&#xa0;90% gamma passing rate in the validation set. However, around 2.5&#xa0;Gy dose differences were observed at the skin and tissue interface regions. CONCLUSIONS: Retrospective electron boost dose reconstruction is feasible with acceptable accuracy, and could increase data completeness in large cohort studies. Caution is advised when assessing dose near tissue interface and further validation is needed outside the REQUITE dataset.

Electrons↗

Genetic predictors of adverse radiotherapy effects: the Gene-PARE project.

PURPOSE: The development of adverse effects resulting from the radiotherapy of cancer limits the use of this treatment modality. The validation of a test capable of predicting which patients would be most likely to develop adverse responses to radiation treatment, based on the possession of specific genetic variants, would therefore be of value. The purpose of the Genetic Predictors of Adverse Radiotherapy Effects (Gene-PARE) project is to help achieve this goal. METHODS AND MATERIALS: A continuously expanding biorepository has been created consisting of frozen lymphocytes and DNA isolated from patients treated with radiotherapy. In conjunction with this biorepository, a database is maintained with detailed clinical information pertaining to diagnosis, treatment, and outcome. The DNA samples are screened using denaturing high performance liquid chromatography (DHPLC) and the Surveyor nuclease assay for variants in ATM, TGFB1, XRCC1, XRCC3, SOD2, and hHR21. It is anticipated that additional genes that control the biologic response to radiation will be screened in future work. RESULTS: Evidence has been obtained that possession of variants in genes, the products of which play a role in radiation response, is predictive for the development of adverse effects after radiotherapy. CONCLUSIONS: It is anticipated that the Gene-PARE project will yield information that will allow radiation oncologists to use genetic data to optimize treatment on an individual basis.

Ataxia Telangiectasia Mutated Proteins↗

Radiation sensitivity of GL261 murine glioma model and enhanced radiation response by flavopiridol.

Response of a solid tumor to radiation treatment depends, in part, on the intrinsic radiosensitivity of tumor cells, the proliferation rate of tumor cells between radiation treatments and the hypoxic state of the tumor cells. A successful radiosensitizing agent would target S-phase cells and hypoxia. Recently, we demonstrated the anti-tumor effects of flavopiridol in the GL261 murine glioma model might involve 1) recruitment of tumor cells to S-phase (Newcomb et al Cell Cycle 2004; 3:230-234) and 2) an anti-angiogenic effect on the tumor vasculature by downregulation of hypoxia-inducible factor -1alpha (HIF-1alpha) (Newcomb et al Neuro-Oncology 2005; 7:225-235). Given that flavopiridol has demonstrated radiosensitizing activity in several murine tumor models, we tested whether it would enhance the response of GL261 tumors to radiation. In the present study, we evaluated the intrinsic radiation sensitivity of the GL261 glioma model using the tumor control/cure dose of radiation assay (TCD(50)). We found that a single dose of 65 Gy (CI 57.1-73.1) was required to cure 50% of the tumors locally. Using the tumor growth delay assay, fractionated radiation (5 fractions of 5 Gy over 10 days) combined with flavopiridol (5 mg/kg) given three times weekly for 3 cycles produced a significant growth delay. Our results indicate that the GL261 murine glioma model mimics the radioresistance encountered in human gliomas, and thus should prove useful in identifying promising new investigational radiosensitizers for use in the treatment of glioma patients.

Animals↗

ATM sequence variants and risk of radiation-induced subcutaneous fibrosis after postmastectomy radiotherapy.

PURPOSE: To examine the hypothesis that women who are carriers of genetic alterations in the ATM gene are more likely to develop subcutaneous fibrosis after radiotherapy for treatment of breast cancer compared with patients who do not possess DNA sequence variations in this gene. METHODS AND MATERIALS: DNA samples isolated from fibroblast cell lines established from 41 women treated with postmastectomy radiotherapy for breast cancer were screened for genetic variants in ATM using denaturing high-performance liquid chromatography (DHPLC). A minimum follow-up of 2 years enabled analysis of late effects to generate dose-response curves and to estimate the dose that resulted in a 50% incidence of Grade 3 fibrosis (ED50). RESULTS: A total of 26 genetic alterations in the expressed portions of the ATM gene, or within 10 bases of each exon in regions encompassing putative splice sites, were detected in 22 patients. The ED50 (95% confidence interval) of 60.2 (55.7-65.1) Gy calculated for patients without a sequence variation did not differ significantly from the ED50 of 58.4 (54.0-63.1) Gy for the group of patients with any ATM sequence abnormality. The ED50 of 53.7 (50.2-57.5) Gy for those patients who were either homozygous or heterozygous for the G-->A polymorphism at nucleotide 5557, which results in substitution of asparagine for aspartic acid at position 1853 of the ATM protein, was substantially lower than the ED50 of 60.8 (57.0-64.8) Gy for patients not carriers of this sequence alteration. This resulted in an enhancement ratio (ratio of the ED50 values) of 1.13 (1.05-1.22), which was significantly greater than unity. CONCLUSION: The results of this study suggest an association between the ATM codon 1853 Asn/Asp and Asn/Asn genotypes with the development of Grade 3 fibrosis in breast cancer patients treated with radiotherapy.

Ataxia Telangiectasia Mutated Proteins↗

Biologically effective dose values for prostate brachytherapy: effects on PSA failure and posttreatment biopsy results.

PURPOSE: To analyze the effect of biologically effective dose (BED) values on prostate-specific antigen (PSA) failure and posttreatment biopsy. METHODS AND MATERIALS: From 1990 to 2003, 1,377 patients had prostate brachytherapy alone (I-125 or Pd-103) (571), hormonal and brachytherapy (371), and trimodality therapy (hormonal, implant, and external beam) (435). Dose was defined as the D90 (dose delivered to 90% of the gland from the dose-volume histogram). RESULTS: Freedom from PSA failure (FFPF) at 10 years was 87%. The 10-year FFPF for BED<100, >100-120, >120-140, >140-160, <160-180, >180-200, and >200 were 46%, 68%, 81%, 85.5%, 90%, 90%, and 92%, respectively (p<0.0001). BED and Gleason score had the greatest effect, with p values of p<0.0001 in multivariate analysis. Posttreatment positive biopsy rate was 7% (31/446). The positive biopsy rates for BED 100-120, >120-140, >140-160, >160-180, >180-200, and >200 were 24% (8/33), 15% (3/20), 6% (2/33), 6% (3/52), 7% (6/82), 1% (1/72), and 3% (4/131), respectively (p<0.0001). BED was the most significant predictor of biopsy outcome in multivariate analysis (p=0.006). CONCLUSIONS: Biologically effective dose equations provide a method of comparing different isotopes and combined therapies in the brachytherapy management of prostate cancer. The effects of BED on FFPF and posttreatment biopsy demonstrate a strong dose-response relationship.

Age Factors↗

Combined subcarcinogenic benzo[a]pyrene and UVA synergistically caused high tumor incidence and mutations in H-ras gene, but not p53, in SKH-1 hairless mouse skin.

Combined subcarcinogenic doses of benzo[a]pyrene (BaP) and UVA induced H-ras, but not p53, gene mutations 8 weeks before tumor emergence in SKH-1 mice. Neither UVA (40 kJ/m2) nor BaP (8 nmol) induced any tumors after mice were topically treated 3 times/week for 25 weeks. However, combined BaP-UVA treatment synergistically increased tumor incidence and multiplicity. All tumors induced by BaP-UVA were malignant. The epidermis was collected from mice treated for 2, 6 and 10 weeks. DNA from UVB- (0.3 kJ/m2) or BaP-UVA-(8 nmol and 40 kJ/m2-induced tumors was isolated and screened for H-ras and p53 mutations. Four types of point mutation, GGC-->GAC, GCC, GTC and CGC, occurred in UVB-induced tumors at H-ras codon 13; and one type of point mutation, GGA-->GAA, at codon 12. Treatment with either BaP alone or BaP-UVA for 10 weeks caused GGA-->GAA mutation at codon 12 or GGC-->GAC mutation at codon 13 in nontumor skin, respectively, as well as in tumors induced by BaP-UVA. All of the 10-week samples treated with either BaP or BaP-UVA showed detectable mutations at codons 12 and 13, but the genetic load was significantly higher in BaP-UVA-treated mice than in those exposed only to BaP. UVA alone induced mutations at codon 12 in only one-third of samples. G-->A mutations induced by BaP or BaP-UVA at position 38 of codon 13 have not been reported previously. C-->T transitions were detected in p53 hot spots of exon 8 in 2 of 19 BaP-UVA-induced tumors but were not found in nontumor skin.

Animals↗

ATM sequence variants are predictive of adverse radiotherapy response among patients treated for prostate cancer.

PURPOSE: To examine whether the presence of sequence variants in the ATM (mutated in ataxia-telangiectasia) gene is predictive for the development of radiation-induced adverse responses resulting from (125)I prostate brachytherapy for early-stage prostate cancer. MATERIALS AND METHODS: Thirty-seven patients with a minimum of 1-year follow-up who underwent (125)I prostate brachytherapy of early-stage prostate cancer were screened for DNA sequence variations in all 62 coding exons of the ATM gene using denaturing high-performance liquid chromatography. The clinical course and postimplant dosimetry for each genetically characterized patient were obtained from a database of 2,020 patients implanted at Mount Sinai Hospital after 1990. RESULTS: Twenty-one ATM sequence alterations located within exons, or in short intronic regions flanking each exon, were found in 16 of the 37 patients screened. For this group, 10 of 16 (63%) exhibited at least one form of adverse response. In contrast, of the 21 patients who did not harbor an ATM sequence variation, only 3 of 21 (14%) manifested radiation-induced adverse responses (p = 0.005). Nine of the patients with sequence alterations specifically possessed missense mutations, which encode for amino acid substitutions and are therefore more likely to possess functional importance. For this group, 7 of 9 (78%) exhibited at least one form of adverse response. In contrast, of the 28 patients who did not have a missense alteration, only 6 of 28 (21%) manifested any form of adverse response to the radiotherapy (p = 0.004). Of the patients with missense variants, 5 of 9 (56%) exhibited late rectal bleeding vs. 1 of 28 (4%) without such alterations (p = 0.002). Of those patients who were at risk for developing erectile dysfunction, 5 of 8 (63%) patients with missense mutations developed prospectively evaluated erectile dysfunction as opposed to 2 of 20 (10%) without these sequence alterations (p = 0.009). CONCLUSIONS: Possession of sequence variants in the ATM gene, particularly those that encode for an amino acid substitution, is predictive for the development of adverse radiotherapy responses among patients treated with (125)I prostate brachytherapy.

Aged↗

Cellular response to DNA damage.

Eukaryotic cells, from yeast to man, possess evolutionarily conserved mechanisms to accurately and efficiently repair the overwhelming majority of DNA damage, thereby ensuring genomic integrity. Important repair pathways include base excision repair, nucleotide excision repair, mismatch repair, non-homologous end-joining, and homologous recombination. Defects in DNA repair processes generally result in susceptibility to cancer and, often, abnormalities in multiple organ systems. While signal transduction pathways have been intensely studied, epigenetic changes occurring in response to DNA damage are rapidly increasing in importance. Effective radiation and chemotherapy sensitization could result from selective inhibition of DNA repair in tumor cells. DNA damage repair is a dynamic field of research where the fruits of basic research often have important clinical implications.

DNA↗

Biologic comparison of partial breast irradiation protocols.

PURPOSE: To analyze the dose/fractionation schedules currently used in ongoing clinical trials of partial breast irradiation (PBI) by comparing their biologically effective dose (BED) values to those of three standard whole breast protocols commonly used after segmental mastectomy in the treatment of breast cancer. METHODS AND MATERIALS: The BED equation derived from the linear-quadratic model for radiation-induced cell killing was used to calculate the BEDs for three commonly used whole breast radiotherapy regimens, in addition to a variety of external beam radiotherapy, as well as high-dose-rate and low-dose-rate brachytherapy, PBI protocols. RESULTS: The BED values of most PBI protocols resulted in tumor control BEDs roughly equivalent to a 50-Gy standard treatment, but consistently lower than the BEDs for regimens in which the tumor bed receives a total dose of either 60 Gy or 66 Gy. The BED values calculated for the acute radiation responses of erythema and desquamation were nearly all lower for the PBI schedules, and the late-response BEDs for most PBI regimens were in a similar range to the BEDs for the standard treatments. CONCLUSION: Biologically effective dose modeling raises the concern that inadequate doses might be delivered by PBI to ensure optimal in-field tumor control.

Brachytherapy↗

Study design: evaluating gene-environment interactions in the etiology of breast cancer - the WECARE study.

INTRODUCTION: Deficiencies in cellular responses to DNA damage can predispose to cancer. Ionizing radiation can cause cluster damage and double-strand breaks (DSBs) that pose problems for cellular repair processes. Three genes (ATM, BRCA1, and BRCA2) encode products that are essential for the normal cellular response to DSBs, but predispose to breast cancer when mutated. DESIGN: To examine the joint roles of radiation exposure and genetic susceptibility in the etiology of breast cancer, we designed a case-control study nested within five population-based cancer registries. We hypothesized that a woman carrying a mutant allele in one of these genes is more susceptible to radiation-induced breast cancer than is a non-carrier. In our study, 700 women with asynchronous bilateral breast cancer were individually matched to 1400 controls with unilateral breast cancer on date and age at diagnosis of the first breast cancer, race, and registry region, and counter-matched on radiation therapy. Each triplet comprised two women who received radiation therapy and one woman who did not. Radiation absorbed dose to the contralateral breast after initial treatment was estimated with a comprehensive dose reconstruction approach that included experimental measurements in anthropomorphic and water phantoms applying patient treatment parameters. Blood samples were collected from all participants for genetic analyses. CONCLUSIONS: Our study design improves the potential for detecting gene-environment interactions for diseases when both gene mutations and the environmental exposures of interest are rare in the general population. This is particularly applicable to the study of bilateral breast cancer because both radiation dose and genetic susceptibility have important etiologic roles, possibly by interactive mechanisms. By using counter-matching, we optimized the informativeness of the collected dosimetry data by increasing the variability of radiation dose within the case-control sets and enhanced our ability to detect radiation-genotype interactions.

Adult↗

Designing and implementing quality control for multi-center screening of mutations in the ATM gene among women with breast cancer.

Epidemiologic studies of breast and other cancers are increasingly turning toward large, multi-center designs in order to obtain adequate power to detect low-penetrance susceptibility alleles. The size of such studies often makes it necessary to distribute the genetic screening efforts to multiple sites. Careful standardization of screening methodology and quality control across sites is required for such multi-center screening designs to be efficient. In this report, we illustrate our approach to these challenges in the context of the WECARE (Women's Environment, Cancer and Radiation Epidemiology) Study, a multi-center population-based genetic epidemiologic study of women with unilateral and bilateral breast cancer. We provide optimized conditions for screening the ataxia-telangiectasia gene (ATM) for variation by denaturing high-performance liquid chromatography (DHPLC) and describe the results of two independent quality control studies at four international centers employing these conditions. Finally, we report novel mutations in the ATM gene identified both in patients with ataxia-telangiectasia and in patients with unilateral or bilateral breast cancer.

Ataxia Telangiectasia Mutated Proteins↗

Toward a national consensus: teaching radiobiology to radiation oncology residents.

PURPOSE: The ASTRO Joint Working Group on Radiobiology Teaching, a committee composed of members having affiliations with several national radiation oncology and biology-related societies and organizations, commissioned a survey designed to address issues of manpower, curriculum standardization, and instructor feedback as they relate to resident training in radiation biology. METHODS AND MATERIALS: Radiation biology instructors at U.S. radiation oncology training programs were identified and asked to respond to a comprehensive electronic questionnaire dealing with instructor educational background, radiation biology course content, and sources of feedback with respect to curriculum planning and resident performance on standardized radiation biology examinations. RESULTS: Eighty-five radiation biology instructors were identified, representing 73 radiation oncology residency training programs. A total of 52 analyzable responses to the questionnaire were received, corresponding to a response rate of 61.2%. CONCLUSION: There is a decreasing supply of instructors qualified to teach classic, and to some extent, clinical, radiobiology to radiation oncology residents. Additionally, those instructors with classic training in radiobiology are less likely to be comfortable teaching cancer molecular biology or other topics in cancer biology. Thus, a gap exists in teaching the whole complement of cancer and radiobiology curricula, particularly in those programs in which the sole responsibility for teaching falls to one faculty member (50% of training programs are in this category). On average, the percentage of total teaching time devoted to classic radiobiology (50%), clinical radiobiology (30%), and molecular and cancer biology (20%) is appropriate, relative to the current makeup of the board examination. Nevertheless large variability exists between training programs with respect to the total number of contact hours per complete radiobiology course (ranging from approximately 10 to >50 h). A number of lecture topics, particularly in clinical radiobiology, are covered by fewer than 60% of training programs. A sizeable minority of radiation biology instructors are dissatisfied with the feedback they receive with respect to both course content and the performance of their residents on standardized radiobiology examinations administered by the American College of Radiology and/or the American Board of Radiology.

Curriculum↗

ATM mutations in female breast cancer patients predict for an increase in radiation-induced late effects.

PURPOSE: Mutation of the ATM gene may be associated with enhanced radiosensitivity and increased radiation-induced morbidity. Denaturing high performance liquid chromatography (DHPLC) is a powerful new technique proven to be sensitive and accurate in the detection of missense mutations, as well as small deletions and insertions. We screened female breast cancer patients for evidence of ATM gene alterations using DHPLC. This study attempted to determine whether breast cancer patients who develop severe radiotherapy (RT)-induced effects are more likely to possess ATM mutations than patients who display normal radiation responses. METHODS AND MATERIALS: Forty-six patients with early-stage breast carcinoma underwent limited surgery and adjuvant RT. DNA was isolated from blood lymphocytes, and each coding exon of the ATM gene was amplified using polymerase chain reaction. Genetic variants were identified using DHPLC by comparing test patterns with a known wild-type pattern. All variants were subjected to DNA sequencing and compared with wild-type sequences for evidence of a mutation. A retrospective review was performed, and the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer acute and late morbidity scoring schemes for skin and subcutaneous normal tissues were applied to quantify the radiation-induced effects. RESULTS: Nine ATM mutations were identified in 6 patients (8 novel and 1 rare). The median follow-up was 3.2 years (range 1.3-10.3). A significant correlation between ATM mutation status and the development of Grade 3-4 subcutaneous late effects was found. All 3 of the patients (100%) who manifested Grade 3-4 subcutaneous late sequelae possessed ATM mutations, whereas only 3 (7%) of the 43 patients who did not develop this form of severe toxicity harbored an ATM mutation (p = 0.001). One ATM mutation carrier developed Grade 4 soft tissue necrosis after RT and required hyperbaric oxygen. All 3 patients manifesting Grade 3-4 late subcutaneous responses in fact harbored 2 ATM mutations. In contrast, none of the 3 ATM carriers who had a single mutation developed a severe subcutaneous reaction. ATM mutation status did not predict for a significant increase in early effects. Of the 23 patients with Grade 2-3 moist desquamation, 4 (17%) had an ATM mutation compared with 2 (9%) of 23 patients without desquamation (p = 0.7). CONCLUSION: Possession of an ATM mutation, particularly when 2 are present, may be predictive of an increase in subcutaneous late tissue effects after RT for breast cancer and may subsequently prove to be a relative contraindication to standard management. These patients may be better served with reduced doses of radiation. Equivalent local control remains to be tested, but this germline alteration may radiosensitize normal tissues, as well as the tumor itself. DHPLC is effective in the identification of these patients. A larger study is required to confirm these findings.

Adult↗

Toward a consensus on radiobiology teaching to radiation oncology residents.

There are approximately 82 radiation oncology residency programs in the United States, which provide training opportunities for about 400 residents. All accredited radiation oncology residency programs must have at least one basic scientist on the faculty, and it is these individuals who often assume, wholly or in part, the responsibility of teaching radiation and cancer biology to radiation oncology residents in preparation for the American College of Radiology (ACR) In-Training Examination in Radiation Oncology and the American Board of Radiology (ABR) written examinations. In response to a perceived lack of uniformity in radiation and cancer biology curricula currently being taught to residents and a perceived lack of guidance for instructors in formulating course content for this population, a special session was presented at the Forty-eighth Annual Radiation Research Society meeting on April 23, 2001. The session, entitled "Toward a Consensus on Radiobiology Teaching to Radiation Oncology Residents", was focused on issues related to teaching radiobiology to radiation oncology residents and targeted for individuals who actively teach radiation and cancer biology as well as coordinators of residency training programs. The speakers addressed current challenges and future problems facing instructors and programs. Among these were lack of feedback on resident performance on ABR and ACR written examinations and on course content, uncertainty about what topics residents must know to pass the ABR examination, and, in the near future, a reduction (due to retirement) of instructors qualified to teach radiobiology. This article provides a synopsis of the information that was presented during that session, offers a glimpse into how the ABR and ACR examinations are prepared and details of the content of past and future examinations, and summarizes the activities of the Joint Working Group on Radiobiology Teaching which was formed to educate instructors, to establish a consensus for course curricula, and to improve the overall quality of resident teaching.

Consensus Statements as Topic↗