15 research outputs found

    Recorridos y debates en torno al concepto de cultura en antropología: una propuesta de aproximación

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    In this article we aim to carry out a brief presentation of some conceptualizations that the notion of culture has acquired in the anthropological field and, at the same time, problematize the social, political and economic contexts in which these ideas have gestated. En este artículo nos proponemos realizar un breve recorrido por algunas acepciones que fue adquiriendo el concepto de cultura en las ciencias antropológicas, problematizando los contextos sociales, políticos y económicos en los que esas ideas fueron gestadas. Neste artigo propomos realizar um breve percurso por alguns significados que o conceito de cultura foi adquirindo nas ciências antropológicas, problematizando os contextos sociais, políticos e econômicos em que essas ideias foram gestadas.&nbsp

    The impact of protocol assignment for older adolescents with Hodgkin lymphoma

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    Background and Purpose: Hodgkin lymphoma (HL) treatment has evolved to reduce or avoid radiotherapy (RT) dose and volume and minimize the potential for late effects. Some older adolescents are treated on adult protocols. The purpose of this study is to examine the protocol assignment of older adolescents and its impact on radiation dose to relevant thoracic structures. Materials and Methods: Cooperative group data were reviewed and 12 adolescents were randomly selected from a pediatric HL protocol. Treatment plans were generated per one pediatric and two adult protocols. Dose volume histograms for heart, lung, and breast allowed comparison of radiation dose to these sites across these three protocols. Results: A total of 15.2% of adolescents were treated on adult HL protocols and received significantly higher radiation dosage to heart and lung compared to pediatric HL protocols. Adolescents treated on either pediatric or adult protocols received similar RT dose to breast. Conclusion: Older adolescents treated on adult HL protocols received higher RT dose to thoracic structures except breast. Level of nodal involvement may impact overall RT dose to breast. The impact of varying field design and RT dose on survival, local, and late effects needs further study for this vulnerable age group

    Essentials in Accident and Emergency Medicine Radiation Injury: Response and Treatment

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    The discovery of radiation has enabled great healthcare advances as well as catastrophic injury. This paper reviews major historical incidents of public radiation exposure and the evolution of standards affecting today’s public and health care workers. Current patient care and response assessment to radiation exposure are reviewed. The strengths of modern radiation therapy and the need for continuous process improvements to ensure optimal patient care and secure safe environments are identified. The discovery of radiation has brought significant scientific achievements as well as catastrophic injury

    Local Control For High-Grade Nonrhabdomyosarcoma Soft Tissue Sarcoma Assigned to Radiation Therapy on ARST0332: A Report From the Childrens Oncology Group

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    PURPOSE: The ARST0332 trial for pediatric and young adults with nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) used risk-based treatment including primary resection with lower-than-standard radiation doses to optimize local control (LC) while minimizing long-term toxicity in those requiring radiation therapy (RT). RT for high-grade NRSTS was based on extent of resection (R0: negative margins, R1: microscopic margins, R2/U: gross disease/unresectable); those with \u3e 5 cm tumors received chemotherapy (CT; ifosfamide/doxorubicin). This analysis evaluates LC for patients assigned to RT and prognostic factors associated with local recurrence (LR). METHODS AND MATERIALS: Patients aged \u3c 30 years with high-grade NRSTS received RT (55.8 Gy) for R1 \u3c /=5 cm tumor (arm B); RT (55.8 Gy)/CT for R0/R1 \u3e 5 cm tumor (arm C); or neoadjuvant RT (45 Gy)/CT plus delayed surgery, CT, and postoperative boost to 10.8 Gy R0 \u3c 5 mm margins/R1 or 19.8 Gy for R2/unresected tumors (arm D). RESULTS: One hundred ninety-three eligible patients had 24 LRs (arm B 1/15 [6.7%], arm C 7/65 [10.8%], arm D 16/113 [14.2%]) at median time to LR of 1.1 years (range, 0.11-5.27). Of 95 eligible for delayed surgery after neoadjuvant therapy, 89 (93.7%) achieved R0/R1 margins. Overall LC after RT were as follows: R0, 106 of 109 (97%); R1, 51 of 60 (85%); and R2/unresectable, 2 of 6 (33%). LR predictors include extent of delayed resection (P \u3c .001), imaging response before delayed surgery (P \u3c .001), histologic subtype (P \u3c .001), and no RT (P = .046). The 5-year event-free survival was significantly lower (P = .0003) for patients unable to undergo R0/R1 resection. CONCLUSIONS: Risk-based treatment for young patients with high-grade NRSTS treated on ARST0332 produced very high LC, particularly after R0 resection (97%), despite lower-than-standard RT doses. Neoadjuvant CT/RT enabled delayed R0/R1 resection in most patients and is preferred over adjuvant therapy due to the lower RT dose delivered

    Pulmonary toxicity in Stage III non-small cell lung cancer patients treated with high-dose (74 Gy) 3-dimensional conformal thoracic radiotherapy and concurrent chemotherapy following induction chemotherapy: a secondary analysis of Cancer and Leukemia Group B (CALGB) trial 30105

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    PURPOSE: Cancer and Leukemia Group B (CALGB) 30105 tested two different concurrent chemoradiotherapy platforms with high-dose (74 Gy) three-dimensional conformal radiotherapy (3D-CRT) after two cycles of induction chemotherapy for Stage IIIA/IIIB non-small cell lung cancer (NSCLC) patients to determine if either could achieve a primary endpoint of \u3e18-month median survival. Final results of 30105 demonstrated that induction carboplatin and gemcitabine and concurrent gemcitabine 3D-CRT was not feasible because of treatment-related toxicity. However, induction and concurrent carboplatin/paclitaxel with 74 Gy 3D-CRT had a median survival of 24 months, and is the basis for the experimental arm in CALGB 30610/RTOG 0617/N0628. We conducted a secondary analysis of all patients to determine predictors of treatment-related pulmonary toxicity. METHODS AND MATERIALS: Patient, tumor, and treatment-related variables were analyzed to determine their relation with treatment-related pulmonary toxicity. RESULTS: Older age, higher N stage, larger planning target volume (PTV)1, smaller total lung volume/PTV1 ratio, larger V20, and larger mean lung dose were associated with increasing pulmonary toxicity on univariate analysis. Multivariate analysis confirmed that V20 and nodal stage as well as treatment with concurrent gemcitabine were associated with treatment-related toxicity. A high-risk group comprising patients with N3 disease and V20 \u3e38% was associated with 80% of Grades 3-5 pulmonary toxicity cases. CONCLUSIONS: Elevated V20 and N3 disease status are important predictors of treatment related pulmonary toxicity in patients treated with high-dose 3D-CRT and concurrent chemotherapy. Further studies may use these metrics in considering patients for these treatments

    Effect of radiotherapy techniques (IMRT vs. 3D-CRT) on outcome in patients with intermediate-risk rhabdomyosarcoma enrolled in COG D9803--a report from the Children\u27s Oncology Group

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    PURPOSE: To compare the dosimetric parameters of intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT) in patients with intermediate-risk rhabdomyosarcoma and to analyze their effect on locoregional control and failure-free survival (FFS). METHODS AND MATERIALS: The study population consisted of 375 patients enrolled in the Children\u27s Oncology Group protocol D9803 study, receiving IMRT or 3D-CRT. Dosimetric data were collected from 179 patients with an available composite plan. The chi-square test or Fisher\u27s exact test was used to compare the patient characteristics and radiotherapy parameters between the two groups. The interval-to-event outcomes were estimated using the Kaplan-Meier method and compared using log-rank tests. Cox proportional hazards regression analysis was used to examine the effect of the treatment technique on FFS after adjusting for primary site and risk group. RESULTS: The median follow-up time was 5.7 and 4.2 years for patients receiving 3D-CRT and IMRT, respectively. No differences in the 5-year failure of locoregional control (18% vs. 15%) or FFS (72% vs. 76%) rates were noted between the two groups. Multivariate analysis revealed no association between the two techniques and FFS. Patients with primary tumors in parameningeal sites were more likely to receive IMRT than 3D-CRT. IMRT became more common during the later years of the study. Patients receiving IMRT were more likely to receive \u3e50 Gy, photon energy of 5 radiation fields than those who received 3D-CRT. The coverage of the IMRT planning target volume by the prescription dose was improved compared with the coverage using 3D-CRT with similar target dose heterogeneity. CONCLUSIONS: IMRT improved the target dose coverage compared with 3D-CRT, although an improvement in locoregional control or FFS could not be demonstrated in this population. Future studies comparing the integral dose to nontarget tissue and late radiation toxicity between the two groups are warranted

    Preoperative Intensity Modulated Radiation Therapy Compared to Three-Dimensional Conformal Radiation Therapy for High-Grade Extremity Sarcomas in Children: Analysis of the Children\u27s Oncology Group Study ARST0332

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    PURPOSE: For pediatric patients with large, high-grade, extremity nonrhabdomyosarcoma soft-tissue sarcomas, preoperative radiation therapy (RT) provides the opportunity for smaller radiation fields and tumor shrinkage resulting in less extensive surgery. The potential disadvantage is an increased risk of wound complications after surgery compared with rates after postoperative chemoradiation. We assessed the impact of preoperative RT technique on target coverage in relationship to dose to skin and adjacent joints to determine whether acute wound complications and late musculoskeletal injury might be influenced by treatment technique. METHODS AND MATERIALS: Of 550 eligible patients \u3c 30 years of age, 200 were enrolled in arm D of ARST0332 and received neoadjuvant ifosfamide/doxorubicin, then chemoradiotherapy (45 Gy and ifosfamide) and surgery followed by postoperative RT if gross or microscopic positive surgical margins. One-hundred thirteen patients had extremity nonrhabdomyosarcoma soft-tissue sarcomas, of which 56 patients had preoperative RT plans for digital review. The doses to the target volume, skin (surface to 5 mm depth), adjacent joint, and extremity diameter were analyzed with respect to RT technique. RESULTS: Thirty-eight patients (65%) received 3-dimensional conformal RT (3D-CRT) and 18 (32%) received intensity modulated RT (IMRT). There was no difference in clinical target volume (CTV) size between groups (P = .920); however, IMRT plans had improved CTV coverage to 100% of the prescription dose compared with 3D-CRT plans (median CTV coverage, 92.7% vs 98.6%; P = .011). In patients without target overlap with the skin, IMRT use was associated with reduced percent volume of skin receiving 45 Gy or more (V45Gy) compared with 3D-CRT (median, 1.6% vs 6.3%, respectively; P = .005). IMRT was also associated with reduced V45Gy to the adjacent joint compared with 3D-CRT (median, 1.1% vs 13.2%; P = .018). CONCLUSIONS: Preoperative IMRT may improve CTV coverage and reduce the volume of skin and adjacent joint treated to high doses. Future studies should assess whether these dosimetric findings produce differences in clinical and toxicity outcomes

    Quality assurance in radiation oncology

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    The Children\u27s Oncology Group (COG) has a strong quality assurance (QA) program managed by the Imaging and Radiation Oncology Core (IROC). This program consists of credentialing centers and providing real-time management of each case for protocol compliant target definition and radiation delivery. In the International Society of Pediatric Oncology (SIOP), the lack of an available, reliable online data platform has been a challenge and the European Society for Paediatric Oncology (SIOPE) quality and excellence in radiotherapy and imaging for children and adolescents with cancer across Europe in clinical trials (QUARTET) program currently provides QA review for prospective clinical trials. The COG and SIOP are fully committed to a QA program that ensures uniform execution of protocol treatments and provides validity of the clinical data used for analysis

    Local Control For High-Grade Nonrhabdomyosarcoma Soft Tissue Sarcoma Assigned to Radiation Therapy on ARST0332: A Report From the Childrens Oncology Group

    No full text
    PurposeThe ARST0332 trial for pediatric and young adults with nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) used risk-based treatment including primary resection with lower-than-standard radiation doses to optimize local control (LC) while minimizing long-term toxicity in those requiring radiation therapy (RT). RT for high-grade NRSTS was based on extent of resection (R0: negative margins, R1: microscopic margins, R2/U: gross disease/unresectable); those with >5 cm tumors received chemotherapy (CT; ifosfamide/doxorubicin). This analysis evaluates LC for patients assigned to RT and prognostic factors associated with local recurrence (LR).Methods and materialsPatients aged <30 years with high-grade NRSTS received RT (55.8 Gy) for R1 ≤5 cm tumor (arm B); RT (55.8 Gy)/CT for R0/R1 >5 cm tumor (arm C); or neoadjuvant RT (45 Gy)/CT plus delayed surgery, CT, and postoperative boost to 10.8 Gy R0 <5 mm margins/R1 or 19.8 Gy for R2/unresected tumors (arm D).ResultsOne hundred ninety-three eligible patients had 24 LRs (arm B 1/15 [6.7%], arm C 7/65 [10.8%], arm D 16/113 [14.2%]) at median time to LR of 1.1 years (range, 0.11-5.27). Of 95 eligible for delayed surgery after neoadjuvant therapy, 89 (93.7%) achieved R0/R1 margins. Overall LC after RT were as follows: R0, 106 of 109 (97%); R1, 51 of 60 (85%); and R2/unresectable, 2 of 6 (33%). LR predictors include extent of delayed resection (P <.001), imaging response before delayed surgery (P < .001), histologic subtype (P <.001), and no RT (P = .046). The 5-year event-free survival was significantly lower (P = .0003) for patients unable to undergo R0/R1 resection.ConclusionsRisk-based treatment for young patients with high-grade NRSTS treated on ARST0332 produced very high LC, particularly after R0 resection (97%), despite lower-than-standard RT doses. Neoadjuvant CT/RT enabled delayed R0/R1 resection in most patients and is preferred over adjuvant therapy due to the lower RT dose delivered
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