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Background: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) may provide biomarkers of the outcome of locally-advanced cervical carcinoma (LACC). There is, however, no agreement on how DCE-MR recordings should be analyzed. Previously, we have analyzed DCE-MRI data of LACC using non-model-based strategies. In the current study, we analyzed DCE-MRI data of LACC using the Tofts pharmacokinetic model, and the biomarkers derived from this analysis were compared with those derived from the non-model-based analyses.Methods: Eighty LACC patients given cisplatin-based chemoradiotherapy with curative intent were included in the study. Treatment outcome was recorded as disease-free survival (DFS) and overall survival (OS). DCE-MRI series were analyzed voxelwise to produce Ktrans and ve frequency distributions, and ROC analysis was used to identify the parameters of the frequency distributions having the greatest potential as biomarkers. The prognostic power of these parameters was compared with that of the non-model-based parameters LETV (low-enhancing tumor volume) and TVIS (tumor volume with increasing signal).Results: Poor DFS and OS were associated with low values of Ktrans, whereas there was no association between treatment outcome and ve. The Ktrans parameters having the greatest prognostic value were p35-Ktrans (the Ktrans value at the 35 percentile of a frequency distribution) and RV-Ktrans (the tumor subvolume with Ktrans values below 0.13 min- 1). Multivariate analysis including clinical parameters and p35-Ktrans or RV-Ktrans revealed that RV-Ktrans was the only independent prognostic factor of DFS and OS. There were significant correlations between RV-Ktrans and LETV and between RV-Ktrans and TVIS, and the prognostic power of RV-Ktrans was similar to that of LETV and TVIS.Conclusions: Biomarkers of the outcome of LACC can be provided by analyzing DCE-MRI series using the Tofts pharmacokinetic model. However, these biomarkers do not appear to have greater prognostic value than biomarkers determined by non-model-based analyses. [ABSTRACT FROM AUTHOR]

Background: There is significant evidence that DCE-MRI may have the potential to provide clinically useful biomarkers of the outcome of locally advanced cervical carcinoma. However, there is no consensus on how to analyze DCE-MRI data to arrive at the most powerful biomarkers. The purpose of this study was to analyze DCE-MRI data of cervical cancer patients by using the Brix pharmacokinetic model and to compare the biomarkers derived from the Brix analysis with biomarkers determined by non-model-based analysis [i.e., low-enhancing tumor volume (LETV) and tumor volume with increasing signal (TVIS)] of the same patient cohort. Material and methods: DCE-MRI recordings of 80 patients (FIGO stage IB–IVA) treated with concurrent cisplatin-based chemoradiotherapy were analyzed voxel-by-voxel, and frequency distributions of the three parameters of the Brix model (ABrix, kep, and kel) were determined. Moreover, risk volumes were calculated from the Brix parameters and termed RV-ABrix, RV-kep, and RV-kel, where the RVs represent the tumor volume with voxel values below a threshold value determined by ROC analysis. Disease-free survival (DFS) and overall survival (OS) were used as measures of treatment outcome. Results: Significant associations between the median value or any other percentile value of ABrix, kep, or kel and treatment outcome were not found. However, RV-ABrix, RV-kep, and RV-kel correlated with DFS and OS. Multivariate analysis revealed that the prognostic power of RV-ABrix, RV-kep, and RV-kel was independent of well-established clinical prognostic factors. RV-ABrix, RV-kep, and RV-kel correlated with each other as well as with LETV and TVIS. Conclusion: Strong biomarkers of the outcome of locally advanced cervical carcinoma can be provided by subjecting DCE-MRI series to pharmacokinetic analysis using the Brix model. The prognostic power of these biomarkers is not necessarily superior to that of biomarkers identified by non-model-based analyses. [ABSTRACT FROM AUTHOR]

Background:Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) may provide prognostic biomarkers for cervix carcinoma. We have shown previously that the early phase of the signal intensity-versus-time curve (SITC) may have significant prognostic power. The purpose of the present investigation was to explore the prognostic value of the late phase of the SITC. Material and methods:DCE-MRI data of 80 patients (FIGO stage IB–IVA) treated with concurrent chemoradiotherapy were examined. Four parameters were calculated from the late-phase SITC: tumor volume with decreasing signal, tumor fraction with decreasing signal, tumor volume with increasing signal (TVIS), and tumor fraction with increasing signal. Results:Multivariate analysis involving clinical parameters and late-phase SITC parameters suggested that TVIS is a strong independent prognostic factor for both disease-free and overall survival. When early-phase SITC parameters were included in the multivariate analysis, the early-phase SITC, but not the late-phase SITC, was found to have independent prognostic value. Conclusion:The late-phase SITC can provide prognostic factors for the outcome of cervix carcinoma, that is, a large tumor volume with increasing late-phase SITCs is associated with poor outcome. However, the prognostic power of the late-phase SITC is not as strong as that of the early-phase SITC. [ABSTRACT FROM AUTHOR]

Introduction. Pharmacokinetic analysis of dynamic contrast enhanced magnetic resonance images (DCEMRI) allows for quantitative characterization of vascular properties of tumors. The aim of this study is twofold, first to determine if tumor regions with similar vascularization could be labeled by clustering methods, second to determine if the identified regions can be associated with local cancer relapse. Materials and methods. Eighty-one patients with locally advanced cervical cancer treated with chemoradiotherapy underwent DCEMRI with Gd-DTPA prior to external beam radiotherapy. The median follow-up time after treatment was four years, in which nine patients had primary tumor relapse. By fitting a pharmacokinetic two-compartment model function to the temporal contrast enhancement in the tumor, two pharmacokinetic parameters, Ktrans and ύύe, were estimated voxel by voxel from the DCEMR-images. Intratumoral regions with similar vascularization were identified by k-means clustering of the two pharmacokinetic parameter estimates over all patients. The volume fraction of each cluster was used to evaluate the prognostic value of the clusters. Results. Three clusters provided a sufficient reduction of the cluster variance to label different vascular properties within the tumors. The corresponding median volume fraction of each cluster was 38%, 46% and 10%. The second cluster was significantly associated with primary tumor control in a log-rank survival test (p-value: 0.042), showing a decreased risk of treatment failure for patients with high volume fraction of voxels. Conclusions. Intratumoral regions showing similar vascular properties could successfully be labeled in three distinct clusters and the volume fraction of one cluster region was associated with primary tumor control. [ABSTRACT FROM AUTHOR]

Purpose: To compare the severe late effects (Grade 3 or greater) for two groups of cervical cancer patients treated with the same external beam radiotherapy and two high-dose-rate intracavitary brachytherapy regimens and to investigate the influence of the dose delivered each week. Methods and Materials: For 120 patients, intracavitary brachytherapy was delivered with 33.6 Gy in eight fractions to Point A (HD group), and for 119, intracavitary brachytherapy was delivered with 29.4 Gy in seven fractions to Point A (LD group). The cumulative incidence of severe gastrointestinal and genitourinary late effects were calculated for both dose groups using Kaplan-Meier survival analysis. This method was also used to explore whether the number of weeks with different dose levels could predict the cumulative incidence of late effects. Results: The actuarial rate of developing severe gastrointestinal morbidity at 7 years was 10.7% and 8.3% for HD and LD groups, respectively. The rate for genitourinary morbidity was 6.6% for the HD group and 5.0% for the LD group, respectively. No significant difference was found between the two groups. The analyses showed that a marginally significant increase occurred in severe gastrointestinal complications as the number of weeks with a physical dose >20 Gy increased in the HD group (p = .047). Conclusion: To establish dose–response relationships for late complications, three-dimensional imaging and dose–volume histogram parameters are needed. We found some indications that 20 Gy/wk is an upper tolerance level when the dose to the International Commission on Radiation Units and Measurements rectum point is 81 Gyα/β=3 (isoeffective [equivalent] dose of 2-Gy fractions). However, additional investigations using three-dimensional data are needed. [Copyright &y& Elsevier]

Simple Summary: This multicenter retrospective study aimed to describe the outcomes of patients with endometrial cancer after central pelvic/vaginal relapse treated with radical radiotherapy (RT). We included 139 patients with a median follow-up time of 6.66 years. Patients were treated with external beam radiotherapy to elective pelvic lymph-node regions and boost to the pelvic tumor. During follow-up, 55 (39.6%) patients developed a second relapse, the majority (75%) with disease sites outside the radiation field. Risk group at primary diagnosis and type of boost administration were independent predictors of progression-free and overall survival. Five-year overall survival for the whole cohort was 68% (95% CI: 59–75%). The majority of isolated pelvic recurrences in RT-naive women with EC can be successfully salvaged by RT but survival in high-risk patients remains suboptimal. Individualizing of adjuvant treatment in first line and better treatment alternatives at relapse are important to ultimately improve survival. (1) Background: This study evaluated the clinical outcome after salvage radiotherapy for first pelvic relapse after endometrial cancer (EC). (2) Methods: This multicenter retrospective study included EC patients with first central pelvic relapse without lymph node involvement treated with curative intent. Progression-free (PFS) and overall survival (OS) were calculated with the Kaplan–Meier method and possible predictive factors for risk of relapse and mortality were identified using the Cox model. (3) Results: We included 139 patients with median EQD2 (Equivalent Dose in 2 Gy fractions) to the clinical target volume of 70.0 Gy. During follow up of median 6.66 years, 39.6% patients developed a second relapse. Risk group classification at primary diagnosis based on histology, grading and FIGO stage and how the pelvic tumor boost was administered were independently associated with PFS and OS. Five-year OS was 68% (95% CI (59–75)) for the whole cohort. Five-year OS was 88% (95% CI (75–94)), 72% (95% CI (55–84)) and 38% (95% CI (15–60)) for the stage I low-, intermediate- and high-risk group, respectively. (4) Conclusions: The majority of central pelvic recurrences in RT-naive EC women can be successfully salvaged with radiotherapy. However, survival in patients with high-risk disease remains poor and warrants a more individualized approach to optimize outcome. [ABSTRACT FROM AUTHOR]