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PubMed | Grupo IMO, University of Santiago de Compostela, Hospital Universitario Ramon y Cajal, Hospital Of La Esperanza and 2 more.
Type: Journal Article | Journal: Clinical & translational oncology : official publication of the Federation of Spanish Oncology Societies and of the National Cancer Institute of Mexico | Year: 2016

Locally advanced non-small cell lung cancer (NSCLC) is a diversified illness in which postoperative radiation therapy (PORT) for complete resection with positive hiliar (pN1) and/or mediastinal (pN2) lymph nodes is controversial. Although several studies have shown that PORT has beneficial effects, randomized trials are needed to demonstrate its impact on overall survival. In this review, the Spanish Radiation Oncology Group for Lung Cancer describes the most relevant literature on PORT in NSCLC patients stage pN1-2. In addition, we have outlined the current recommendations of different national and international clinical guidelines and have also specified practical issues regarding treatment volume definition, doses and fractionation.

Lopez Guerra J.L.,University of Houston | Lopez Guerra J.L.,Grupo IMO | Gomez D.R.,University of Houston | Lin S.H.,University of Houston | And 9 more authors.
Annals of Oncology | Year: 2013

Background: The purpose of this study was to evaluate the actuarial risk of local and regional failure in patients with completely resected non-small-cell lung cancer (NSCLC), and to assess surgical and pathological factors affecting this risk. Patients and methods: Between January 1998 and December 2009, 1402 consecutive stage I-III (N0-N1) NSCLC patients underwent complete resection without adjuvant radiation therapy. The median follow-up was 42 months. Results: Local-regional recurrence was identified in 9% of patients, with local failure alone in 3% of patients, regional failure alonein 4% of patients, and both local and regional failure simultaneously in 2% of patients. Patients who had local failure were found to be at increased risk of mortality. By multivariate analyses, three variables were shown to be independently significant risk factors for local [surgical procedure (single/multiple wedges + segmentectomy versus lobectomy + bilobectomy + pneumonectomy), tumor size >2.7 cm, and visceral pleural invasion] and regional (pathologic N1stage, visceral pleural invasion, and lymphovascular space invasion, LVI) recurrence, respectively. Conclusion: Patients with N0-N1 disease have low rates of locoregional recurrence after surgical resection. However, several prognostic factors can be identified that increase this risk and identify patients who may benefit from adjuvant treatment. © The Author 2012. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved.

Dos Santos M.A.,Grupo IMO | De Salcedo J.B.P.,Grupo IMO | Gutierrez Diaz J.A.,Grupo IMO | Calvo F.A.,Grupo IMO | And 4 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2011

Purpose: Patients with cavernous sinus meningiomas (CSM) have an elevated risk of surgical morbidity and mortality. Recurrence is often observed after partial resection. Stereotactic radiosurgery (SRS), either alone or combined with surgery, represents an important advance in CSM management, but long-term results are lacking. Methods and Materials: A total of 88 CSM patients, treated from January 1991 to December 2005, were retrospectively reviewed. The mean follow-up was 86.8 months (range, 17.1-179.4 months). Among the patients, 22 were followed for more than 10 years. There was a female predominance (84.1%). The age varied from 16 to 90 years (mean, 51.6). In all, 47 patients (53.4%) received SRS alone, and 41 patients (46.6%) had undergone surgery before SRS. A dose of 14 Gy was prescribed to isodose curves from 50% to 90%. In 25 patients (28.4%), as a result of the proximity to organs at risk, the prescribed dose did not completely cover the target. Results: After SRS, 65 (73.8%) patients presented with tumor volume reduction; 14 (15.9%) remained stable, and 9 (10.2%) had tumor progression. The progression-free survival was 92.5% at 5 years, and 82.5% at 10 years. Age, sex, maximal diameter of the treated tumor, previous surgery, and complete target coverage did not show significant associations with prognosis. Among the 88 treated patients, 17 experienced morbidity that was related to SRS, and 6 of these patients spontaneously recovered. Conclusions: SRS is an effective and safe treatment for CSM, feasible either in the primary or the postsurgical setting. Incomplete coverage of the target did not worsen outcomes. More than 80% of the patients remained free of disease progression during long-term follow-up. © 2011 Elsevier Inc.

Garcia Alvarez G.,Grupo IMO
Revisiones en Cancer | Year: 2012

Radiotherapy is one of the mainstays of cancer treatment. It is estimated that approximately 60% of cancer patients receive radiation therapy over the course of their illness. At present, the cancer disease management is done based on a multidisciplinary treatment which has resulted in increased overall survival. One of the most important objectives to integrate different therapeutic modalities (surgery, chemotherapy and radiotherapy) is to intensify therapy to optimize locoregional control in certain tumors. With the combination of chemotherapy and radiotherapy (RT) the likelihood of local toxicity increased and should be considered in the overall context of the patient. The purpose of RT is to administer therapeutic doses in the tumor, while limiting the volume of healthy tissue exposed to high doses of radiation. However, there area number of factors that influence the toxicity such as general and nutritional status of the patient, previous treatments and concomitant to RT, tumor site, dose per fraction, total dose and treatment technique. Copyright © 2012 Aran Ediciones, S. L.

Sanz A.,Grupo IMO | Olivares M.E.,Servicio Ginecologia y Obstetricia Hospital Clinico San Carlos | Barcia J.A.,Servicio Neurocirugia Hospital Clinico San Carlos
Psicooncologia | Year: 2011

The increased survival of patients with low grade gliomas generated increased interest in the neurotoxic effects associated with treatment, especially radiotherapy. Currently, the radiotherapy is associated with visual memory failures in this population. On the contrary, some authors postulate that radiotherapy, as well as other treatments, helps control the disease and preserves the neuropsychological performance. However, methodological limitations of these studies and the difficulty in monitoring these patients could be causing this divergence in the results found in this research field. Therefore, we note the need for studies that use radiation therapy treatment techniques current, which increase safety and reduce neurological side effects, and apply appropriate questionnaires with a sensitivity to the neurotoxic effects of adjuvant treatments.

Bueno G.,University of Castilla - La Mancha | Deniz O.,University of Castilla - La Mancha | Salido J.,University of Castilla - La Mancha | Carrascosa C.,Hospital General Of Ciudad Real | Delgado J.M.,Grupo IMO
International Journal of Computer Assisted Radiology and Surgery | Year: 2011

Purpose: Organ motion should be taken into account for image-guided fractionated radiotherapy. A deformable segmentation and registration method was developed for inter-and intra-fraction organ motion planning and evaluation. Methods: Energy minimizing active models were synthesized for tracking a set of organs delineated by regions of interest (ROI) in radiotherapy treatment. The initial model consists of a surface deformed to match the ROI contour by geometrical properties, following a heat flow model. The deformable segmentation model was tested using a Shepp-Logan head CT simulation, and different quantitative metrics were applied such as ROC analysis, Jaccard index, Dice coefficient and Hausdorff distance. Results: Experimental evaluation of automated versus manual segmentation was done for the cardiac, thoracic and pelvic regions. The method has been quantitatively validated, obtaining an average of 93.3 and 99.2% for the sensitivity and specificity, respectively, 90.79% for the Jaccard index, 95.15% for the Dice coefficient and 0.96% mm for the Hausdorff distance. Conclusions: Model-based deformable segmentation was developed and tested for image-guided radiotherapy treatment planning. The method is efficient, robust and has sufficient accuracy for 2D CT data without markers. © 2010 CARS.

Lopez Guerra J.L.,University of Houston | Lopez Guerra J.L.,Grupo IMO | Gomez D.,University of Houston | Zhuang Y.,University of Houston | And 7 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2012

Purpose: We investigated prognostic factors associated with survival in patients with non-small cell lung cancer (NSCLC) and oligometastatic disease at diagnosis, particularly the influence of local treatment to the primary site on prognosis. Methods and Materials: From January 2000 through June 2011, 78 consecutive patients with oligometastatic NSCLC (<5 metastases) at diagnosis underwent definitive chemoradiation therapy (≥45 Gy) to the primary site. Forty-four of these patients also received definitive local treatment for the oligometastases. Survival outcomes were estimated using the Kaplan-Meier method, and risk factors were identified by univariate and multivariate analyses. Results: Univariate Cox proportional hazard analysis revealed better overall survival (OS) for those patients who received at least 63 Gy of radiation to the primary site (P=.002), received definitive local treatment for oligometastasis (P=.041), had a Karnofsky performance status (KPS) score >80 (P=.007), had a gross tumor volume ≤124 cm 3 (P=.002), had adenocarcinoma histology (P=.002), or had no history of respiratory disease (P=.016). On multivariate analysis, radiation dose, performance status, and tumor volume retained significance (P=.004, P=.006, and P<.001, respectively). The radiation dose also maintained significance when patients with and without brain metastases were analyzed separately. Conclusions: Tumor volume, KPS, and receipt of at least 63 Gy to the primary tumor are associated with improved OS in patients with oligometastatic NSCLC at diagnosis. Our results suggest that a subset of such patients may benefit from definitive local therapy. © 2012 Elsevier Inc. All rights reserved.

Mansouri S.,Grupo IMO | Naim A.,Grupo IMO | Glaria L.,Grupo IMO | Marsiglia H.,Grupo IMO
Asian Pacific Journal of Cancer Prevention | Year: 2014

Background: Breast cancers are becoming more frequently diagnosed at early stages with improved long term outcomes. Late normal tissue complications induced by radiotherapy must be avoided with new breast radiotherapy techniques being developed. The aim of the study was to compare dosimetric parameters of planning target volume (PTV) and organs at risk between conformal (CRT) and intensity-modulated radiation therapy (IMRT) after breast-conserving surgery. Materials and Methods: A total of 20 patients with early stage left breast cancer received adjuvant radiotherapy after conservative surgery, 10 by 3D-CRT and 10 by IMRT, with a dose of 50 Gy in 25 sessions. Plans were compared according to dose-volume histogram analyses in terms of PTV homogeneity and conformity indices as well as organs at risk dose and volume parameters. Results: The HI and CI of PTV showed no difference between 3D-CRT and IMRT, V95 gave 9.8% coverage for 3D-CRT versus 99% for IMRT, V107 volumes were recorded 11% and 1.3%, respectively. Tangential beam IMRT increased volume of ipsilateral lung V5 average of 90%, ipsilateral V20 lung volume was 13%, 19% with IMRT and 3D-CRT respectively. Patients treated with IMRT, heart volume encompassed by 60% isodose (30 Gy) reduced by average 42% (4% versus 7% with 3D-CRT), mean heart dose by average 35% (495cGy versus 1400 cGy with 3D-CRT). In IMRT minimal heart dose average is 356 cGy versus 90cGy in 3D-CRT. Conclusions: IMRT reduces irradiated volumes of heart and ipsilateral lung in high-dose areas but increases irradiated volumes in low-dose areas in breast cancer patients treated on the left side.

Sevillano D.,Grupo IMO | Minguez C.,Grupo IMO | Sanchez A.,Grupo IMO | Sanchez-Reyes A.,Grupo IMO
Medical Physics | Year: 2012

Purpose: The binary multileaf collimator (MLC) is one of the most important components in helical tomotherapy (HT), as it modulates the dose delivered to the patient. However, methods to ensure MLC quality in HT treatments are lacking. The authors obtained data on the performance of the MLC in treatments administered in their department in order to assess possible delivery errors due to the MLC. Correction methods based on their data are proposed. Methods: Twenty sinograms from treatments delivered using both of the authors HT systems were measured and analyzed by recording the fluence collected by the imaging detector. Planned and actual sinograms were compared using distributions of leaf open time (LOT) errors, as well as differences in fluence reconstructed at each of the 51 projections into which the treatment planning system divides each rotation for optimization purposes. They proposed and applied a method based on individual leaf error correction and the increase in projection time to prevent latency effects when LOT is close to projection time. In order to analyze the dosimetric impact of the corrections, inphantom measurements were made for four corrected treatments. Results: The LOTs measured were consistent with those planned. Most of the mean errors in LOT distributions were within 1 ms with standard deviations of over 4 ms. Reconstructed fluences showed good results, with over 90 of points passing the 3 criterion, except in treatments with a short mean LOT, where the percentage of passing points was as low as 66. Individual leaf errors were as long as 4 ms in some cases. Corrected sinograms improved error distribution, with standard deviations of over 3 ms and increased percentages of points passing 3 in the fluence per angle analysis, especially in treatments with a short mean LOT and those that were more subject to latency effects. The minimum percentage of points within 3 increased to 86. In-phantom measurements of the corrected treatments showed that, while treatments affected by latency effects were improved, those affected by individual leaf errors were not. Conclusions: Measurement of MLC performance in real treatments provides the authors with a valuable tool for ensuring the quality of HT delivery. The LOTs of MLC are very accurate in most cases. Sources of error were found and correction methods proposed and applied. The corrections decreased the amount of LOT errors. The dosimetric impact of these corrections should be evaluated more thoroughly using 3D dose distribution analysis. © 2012 American Association of Physicists in Medicine.

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