Patients Who Undergo Preoperative Chemoradiotherapy for Locally Advanced Rectal Cancer Restaged by Using Diagnostic MR Imaging: A Systematic Review and Meta-Analysis
TL;DR: MR imaging showed heterogeneous results of diagnostic performances for restaging rectal cancer after neoadjuvant treatment, but significantly better results were demonstrated when DW imaging was used or with experienced observers.
Abstract: MR imaging showed moderate results for tumor staging, with significantly better results when diffusion-weighted imaging or experienced observers were used; moderate results were seen for restaging of circumferential resectionmargin, but lymph node staging remains challenging.
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University of Alabama at Birmingham1, University of South Florida2, Vanderbilt University3, City of Hope National Medical Center4, Fox Chase Cancer Center5, University Of Tennessee System6, Brigham and Women's Hospital7, Seattle Cancer Care Alliance8, Case Western Reserve University9, Roswell Park Cancer Institute10, Northwestern University11, Harvard University12, University of Nebraska Medical Center13, University of Utah14, Memorial Sloan Kettering Cancer Center15
TL;DR: This manuscript focuses on the NCCN Guidelines Panel recommendations for the workup, primary treatment, risk reduction strategies, and surveillance specific to DCIS.
Abstract: Ductal carcinoma in situ (DCIS) of the breast represents a heterogeneous group of neoplastic lesions in the breast ducts. The goal for management of DCIS is to prevent the development of invasive breast cancer. This manuscript focuses on the NCCN Guidelines Panel recommendations for the workup, primary treatment, risk reduction strategies, and surveillance specific to DCIS.
1,545 citations
Netherlands Cancer Institute1, The Catholic University of America2, University of Coimbra3, Mater Misericordiae University Hospital4, Memorial Sloan Kettering Cancer Center5, University College London6, Reims University7, Inje University8, Sapienza University of Rome9, Medical University of Vienna10, Karolinska University Hospital11
TL;DR: These expert consensus recommendations can be used as clinical guidelines for primary staging and restaging of rectal cancer using MRI and were constructed through consensus amongst 14 abdominal imaging experts.
Abstract: The article Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting, written by [§§§ AuthorNames §§§].
631 citations
TL;DR: Using pre- and posttreatment MRI data, a radiomics model with excellent performance for individualized, noninvasive prediction of pCR is developed and may be used to identify LARC patients who can omit surgery after chemoradiotherapy.
Abstract: Purpose: To develop and validate a radiomics model for evaluating pathologic complete response (pCR) to neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer (LARC).Experimental Design: We enrolled 222 patients (152 in the primary cohort and 70 in the validation cohort) with clinicopathologically confirmed LARC who received chemoradiotherapy before surgery. All patients underwent T2-weighted and diffusion-weighted imaging before and after chemoradiotherapy; 2,252 radiomic features were extracted from each patient before and after treatment imaging. The two-sample t test and the least absolute shrinkage and selection operator regression were used for feature selection, whereupon a radiomics signature was built with support vector machines. Multivariable logistic regression analysis was then used to develop a radiomics model incorporating the radiomics signature and independent clinicopathologic risk factors. The performance of the radiomics model was assessed by its calibration, discrimination, and clinical usefulness with independent validation.Results: The radiomics signature comprised 30 selected features and showed good discrimination performance in both the primary and validation cohorts. The individualized radiomics model, which incorporated the radiomics signature and tumor length, also showed good discrimination, with an area under the receiver operating characteristic curve of 0.9756 (95% confidence interval, 0.9185-0.9711) in the validation cohort, and good calibration. Decision curve analysis confirmed the clinical utility of the radiomics model.Conclusions: Using pre- and posttreatment MRI data, we developed a radiomics model with excellent performance for individualized, noninvasive prediction of pCR. This model may be used to identify LARC patients who can omit surgery after chemoradiotherapy. Clin Cancer Res; 23(23); 7253-62. ©2017 AACR.
367 citations
Cites methods or result from "Patients Who Undergo Preoperative C..."
...As a functional imaging technique, DWI showed strong potential in detecting subtle cancer cell remnants (28) and added valuable information regarding the responses to chemoradiotherapy in patients with LARC (15, 29)....
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...Previous studies generally used low-dimensional information to evaluate the responses to chemoradiotherapy (23, 28, 30)....
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...Apparent performance and validation of the radiomics model Calibration curves accompanied by the Hosmer–Lemeshow test were plotted to assess the radiomics model; a significance test statistic implied that the model was not perfectly calibrated (28)....
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TL;DR: Clinical assessment afterCRT is the single most accurate modality for identification of CR after CRT, and addition of MRI with DWI further improves the diagnostic performance, and the combination can be recommended as the optimal strategy for a safe and accurate selection of CRafter CRT.
Abstract: Background
The response to chemoradiotherapy (CRT) for rectal cancer can be assessed by clinical examination, consisting of digital rectal examination (DRE) and endoscopy, and by MRI. A high accuracy is required to select complete response (CR) for organ-preserving treatment. The aim of this study was to evaluate the value of clinical examination (endoscopy with or without biopsy and DRE), T2W-MRI, and diffusion-weighted MRI (DWI) for the detection of CR after CRT.
260 citations
Cites background or methods from "Patients Who Undergo Preoperative C..."
...T indicates tumor; arrows indicate scar or residual tumor after CRT. a Typical CR at T2W-MRI, b equivocal image at T2W-MRI, and c obvious residual tumor at T2W-MRI. d Typical endoluminal image of CR with white scar with teleangiectasia. e Small ulcer with smooth edges (arrows) but without residual polypoid tissue....
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...Recently, diffusion-weighted MRI (DWI) has been shown to provide more accuracy than T2W-MRI.(9) Initially in our center we relied on MRI as the first restaging method and used endoscopy for further evaluation when MRI was suggestive of a CR....
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...MRI can provide this additional information, which can be critical for decision making.6 Although MRI has been widely adopted for the primary staging of rectal cancer, restaging after CRT with standard T2-weighted (T2W) MRI is hampered by the difficulty of distinguishing fibrosis from viable tumor, often leading to incorrectly classifying fibrosis as residual tumor.6–8 Recently, diffusion-weighted MRI (DWI) has been shown to provide more accuracy than T2W-MRI.9 Initially in our center we relied on MRI as the first restaging method and used endoscopy for further evaluation when MRI was suggestive of a CR.3,10 With this selection strategy, a substantial part of those with CR was missed....
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...A meta-analysis on response assessment in rectal cancer has shown that DWI improves the diagnostic performance, mainly through increasing the detection rate of response up to 84 %, along with a very low risk of missing residual tumor.(9) In the present study, combined prediction of a CR on clinical assessment as well as MRI including DWI resulted in a very high predictive value for a CR of 98 %....
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TL;DR: T2- Weighted-based radiomics showed better classification performance compared with qualitative assessment at T2-weighted and DW imaging for diagnosing pCR in patients with locally advanced rectal cancer after CRT.
Abstract: Purpose To investigate the value of T2-weighted-based radiomics compared with qualitative assessment at T2-weighted imaging and diffusion-weighted (DW) imaging for diagnosis of clinical complete response in patients with rectal cancer after neoadjuvant chemotherapy-radiation therapy (CRT). Materials and Methods This retrospective study included 114 patients with rectal cancer who underwent magnetic resonance (MR) imaging after CRT between March 2012 and February 2016. Median age among women (47 of 114, 41%) was 55.9 years (interquartile range, 45.4-66.7 years) and median age among men (67 of 114, 59%) was 55 years (interquartile range, 48-67 years). Surgical histopathologic analysis was the reference standard for pathologic complete response (pCR). For qualitative assessment, two radiologists reached a consensus. For radiomics, one radiologist segmented the volume of interest on high-spatial-resolution T2-weighted images. A random forest classifier was trained to separate the patients by their outcomes after balancing the number of patients in each response category by using the synthetic minority oversampling technique. Statistical analysis was performed by using the Wilcoxon rank-sum test, McNemar test, and Benjamini-Hochberg method. Results Twenty-one of 114 patients (18%) achieved pCR. The radiomic classifier demonstrated an area under the curve of 0.93 (95% confidence interval [CI]: 0.87, 0.96), sensitivity of 100% (95% CI: 0.84, 1), specificity of 91% (95% CI: 0.84, 0.96), positive predictive value of 72% (95% CI: 0.53, 0.87), and negative predictive value of 100% (95% CI: 0.96, 1). The diagnostic performance of radiomics was significantly higher than was qualitative assessment at T2-weighted imaging or DW imaging alone (P < .02). The specificity and positive predictive values were significantly higher in radiomics than were at combined T2-weighted and DW imaging (P < .0001). Conclusion T2-weighted-based radiomics showed better classification performance compared with qualitative assessment at T2-weighted and DW imaging for diagnosing pCR in patients with locally advanced rectal cancer after CRT. © RSNA, 2018 Online supplemental material is available for this article.
236 citations
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TL;DR: A new quantity is developed, I 2, which the authors believe gives a better measure of the consistency between trials in a meta-analysis, which is susceptible to the number of trials included in the meta- analysis.
Abstract: Cochrane Reviews have recently started including the quantity I 2 to help readers assess the consistency of the results of studies in meta-analyses. What does this new quantity mean, and why is assessment of heterogeneity so important to clinical practice?
Systematic reviews and meta-analyses can provide convincing and reliable evidence relevant to many aspects of medicine and health care.1 Their value is especially clear when the results of the studies they include show clinically important effects of similar magnitude. However, the conclusions are less clear when the included studies have differing results. In an attempt to establish whether studies are consistent, reports of meta-analyses commonly present a statistical test of heterogeneity. The test seeks to determine whether there are genuine differences underlying the results of the studies (heterogeneity), or whether the variation in findings is compatible with chance alone (homogeneity). However, the test is susceptible to the number of trials included in the meta-analysis. We have developed a new quantity, I 2, which we believe gives a better measure of the consistency between trials in a meta-analysis.
Assessment of the consistency of effects across studies is an essential part of meta-analysis. Unless we know how consistent the results of studies are, we cannot determine the generalisability of the findings of the meta-analysis. Indeed, several hierarchical systems for grading evidence state that the results of studies must be consistent or homogeneous to obtain the highest grading.2–4
Tests for heterogeneity are commonly used to decide on methods for combining studies and for concluding consistency or inconsistency of findings.5 6 But what does the test achieve in practice, and how should the resulting P values be interpreted?
A test for heterogeneity examines the null hypothesis that all studies are evaluating the same effect. The usual test statistic …
45,105 citations
TL;DR: In this article, an evidence-based quality assessment tool called QUADAS was proposed to assess the quality of primary studies of diagnostic accuracy, based on the results of three previously conducted reviews of the diagnostic literature.
Abstract: Background: In the era of evidence based medicine, with systematic reviews as its cornerstone, adequate quality assessment tools should be available. There is currently a lack of a systematically developed and evaluated tool for the assessment of diagnostic accuracy studies. The aim of this project was to combine empirical evidence and expert opinion in a formal consensus method to develop a tool to be used in systematic reviews to assess the quality of primary studies of diagnostic accuracy. Methods: We conducted a Delphi procedure to develop the quality assessment tool by refining an initial list of items. Members of the Delphi panel were experts in the area of diagnostic research. The results of three previously conducted reviews of the diagnostic literature were used to generate a list of potential items for inclusion in the tool and to provide an evidence base upon which to develop the tool. Results: A total of nine experts in the field of diagnostics took part in the Delphi procedure. The Delphi procedure consisted of four rounds, after which agreement was reached on the items to be included in the tool which we have called QUADAS. The initial list of 28 items was reduced to fourteen items in the final tool. Items included covered patient spectrum, reference standard, disease progression bias, verification bias, review bias, clinical review bias, incorporation bias, test execution, study withdrawals, and indeterminate results. The QUADAS tool is presented together with guidelines for scoring each of the items included in the tool. Conclusions: This project has produced an evidence based quality assessment tool to be used in systematic reviews of diagnostic accuracy studies. Further work to determine the usability and validity of the tool continues.
3,468 citations
TL;DR: Common cancer treatments, survival rates, and posttreatment concerns are summarized and the new National Cancer Survivorship Resource Center is introduced, which has engaged more than 100 volunteer survivorship experts nationwide to develop tools for cancer survivors, caregivers, health care professionals, advocates, and policy makers.
Abstract: Although there has been considerable progress in reducing cancer incidence in the United States, the number of cancer survivors continues to increase due to the aging and growth of the population and improvements in survival rates. As a result, it is increasingly important to understand the unique medical and psychosocial needs of survivors and be aware of resources that can assist patients, caregivers, and health care providers in navigating the various phases of cancer survivorship. To highlight the challenges and opportunities to serve these survivors, the American Cancer Society and the National Cancer Institute estimated the prevalence of cancer survivors on January 1, 2012 and January 1, 2022, by cancer site. Data from Surveillance, Epidemiology, and End Results (SEER) registries were used to describe median age and stage at diagnosis and survival; data from the National Cancer Data Base and the SEER-Medicare Database were used to describe patterns of cancer treatment. An estimated 13.7 million Americans with a history of cancer were alive on January 1, 2012, and by January 1, 2022, that number will increase to nearly 18 million. The 3 most prevalent cancers among males are prostate (43%), colorectal (9%), and melanoma of the skin (7%), and those among females are breast (41%), uterine corpus (8%), and colorectal (8%). This article summarizes common cancer treatments, survival rates, and posttreatment concerns and introduces the new National Cancer Survivorship Resource Center, which has engaged more than 100 volunteer survivorship experts nationwide to develop tools for cancer survivors, caregivers, health care professionals, advocates, and policy makers.
3,203 citations
TL;DR: The bivariate model can be seen as an improvement and extension of the traditional sROC approach by reanalyzing the data of a published meta-analysis of diagnostic studies reporting pairs of sensitivity and specificity.
2,582 citations
TL;DR: Stage 0 rectal cancer disease is associated with excellent long-term results irrespective of treatment strategy and Surgical resection may not lead to improved outcome in this situation and may be associated with high rates of temporary or definitive stoma construction and unnecessary morbidity and mortality rates.
Abstract: Multimodality approach is the preferred treatment strategy for distal rectal cancer, including radical surgery, radiotherapy and chemotherapy. A significant proportion of patients managed by surgery, performed according to established oncological principles, appear to benefit from chemoradiation (CRT) therapy either pre- or postoperatively in terms of survival and recurrence rates.
Preoperative CRT may be associated with less acute toxicity, greater tumor response/sensitivity, and higher rates of sphincter-saving procedures when compared with postoperative course.1,2 Furthermore, tumor downstaging may lead to complete clinical response (defined as absence of residual primary tumor clinically detectable) or complete pathologic response (defined as absence of viable tumor cells after full pathologic examination of the resected specimen, pT0N0M0). These situations may be observed in 10% to 30% of patients treated by neoadjuvant CRT and may be referred as stage 0 disease.3–8 Surgical resection of the rectum may be associated with significant morbidity and mortality, and in these patients, with significant rates of stoma construction.9 Moreover, surgical resection may not lead to increased overall and disease-free survival in these patients. For this reason, it has been our policy to carefully follow these patients with complete clinical response assessed after 8 weeks of CRT completion by clinical, endoscopic, and radiologic studies without immediate surgery. Patients considered with incomplete clinical response are referred to radical surgery. Surprisingly, up to 7% of these patients may present complete pathologic response (pT0N0M0) without tumor cells during pathologic examination, despite incomplete clinical response characterized by a residual rectal ulcer.8
To determine the benefit of surgical resection in patients with stage 0 rectal cancer treated by preoperative CRT therapy, we compared long-term results of a group of patients with incomplete clinical response followed by radical surgery versus a group of patients with complete clinical response not operated on.
1,497 citations