International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Oct 2021
Meta AnalysisPrognostic Importance of MRI-Detected Extramural Venous Invasion in Rectal Cancer: A Literature Review and Systematic Meta-Analysis.
Extramural venous invasion (EMVI) is recognized as a poor prognostic factor in rectal cancer. There are well-documented limitations associated with pathology detection of EMVI, including variable reporting and the inability to use it preoperatively to guide neoadjuvant treatment. Magnetic resonance imaging (MRI)-detected EMVI (mrEMVI) has been proposed as an imaging biomarker. This review assesses the prognostic significance of mrEMVI on survival outcomes and whether regression of mrEMVI after neoadjuvant therapy is associated with improvements in survival. ⋯ mrEMVI is significantly associated with worsened survival outcomes, both at baseline and after neoadjuvant treatment. Additionally, there is evidence that regression of mrEMVI after neoadjuvant treatment is associated with improved survival compared with mrEMVI persistence. The findings of this review emphasize the need for accurate and consistent reporting of mrEMVI status before and after neoadjuvant treatment and support the inclusion of mrEMVI into staging systems preferentially over lymph node metastases.
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 2021
Retraction Of PublicationTEMPORARY REMOVAL: Exercise therapy and radiation therapy (EXERT) for cancer: a systematic review.
Exercise therapy (ET) is shown to improve toxicity and surrogates of survival for patients receiving chemotherapy. Current National Comprehensive Cancer Network (NCCN) guidelines lack recommendations for concurrent radiation therapy (RT) and ET. The main objective was to determine the impact of concurrent ET + RT with respect to (1) acceptability, feasibility, safety; and (2) to demonstrate how incorporating ET in cancer treatment can enhance patient-reported outcomes (PROs) and physical function-defined as strength or exercise capacity. ⋯ Combination ET + RT is safe and well-tolerated with improvements in PROs and physical function. Additional studies are needed in patients with metastatic cancers to assess survival and to compare effectiveness of different exercise regimens.
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 2020
Immortal Time Bias in National Cancer Database Studies.
In studies evaluating the benefit of adjuvant therapies, immortal time bias (ITB) can affect the results by incorrectly reporting a survival advantage. It does so by including all deceased patients who may have been planned to receive adjuvant therapy within the observation cohort. Given the increase in National Cancer Database (NCDB) analyses evaluating postoperative radiation therapy (PORT) as an adjuvant therapy, we sought to examine how often such studies accounted and adjusted for ITB. ⋯ Studies assessing adjuvant radiation therapy by analyzing the NCDB are susceptible to ITB, which overestimates the effect size of adjuvant therapies and can provide misleading results. Adjusting for this bias is essential for accurate data representation and to better quantify the impact of adjuvant therapies such as PORT.
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Radiomics describes the extraction of multiple, otherwise invisible, features from medical images that, with bioinformatic approaches, can be used to provide additional information that can predict underlying tumor biology and behavior. ⋯ Although at an early stage of development, with many technical challenges remaining and a need for standardization, promise nevertheless exists that PET radiomics will contribute to personalized medicine, especially with the availability of increased computing power and the development of machine-learning approaches for imaging.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2018
ReviewRadiomics in Nuclear Medicine Applied to Radiation Therapy: Methods, Pitfalls, and Challenges.
Radiomics is a recent area of research in precision medicine and is based on the extraction of a large variety of features from medical images. In the field of radiation oncology, comprehensive image analysis is crucial to personalization of treatments. A better characterization of local heterogeneity and the shape of the tumor, depicting individual cancer aggressiveness, could guide dose planning and suggest volumes in which a higher dose is needed for better tumor control. ⋯ These difficulties mostly pertain to the variability of the imaging features as a function of the acquisition device and protocol, the robustness of the models with respect to that variability, and the interpretation of the radiomic models. Addressing the impact of the variability in acquisition and reconstruction protocols is needed, as is harmonizing the radiomic feature calculation methods, to ensure the reproducibility of studies in a multicenter context and their implementation in a clinical workflow. In this review, we explain the potential impact of positron emission tomography radiomics for radiation therapy and underline the various aspects that need to be carefully addressed to make the most of this promising approach.