Background
Radiomics or computer‐extracted texture features derived from MRI have been shown to help quantitatively characterize prostate cancer (PCa). Radiomics have not been explored depth in the ...context of predicting biochemical recurrence (BCR) of PCa.
Purpose
To identify a set of radiomic features derived from pretreatment biparametric MRI (bpMRI) that may be predictive of PCa BCR.
Study Type
Retrospective.
Subjects
In all, 120 PCa patients from two institutions, I1 and I2, partitioned into training set D1 (N = 70) from I1 and independent validation set D2 (N = 50) from I2. All patients were followed for ≥3 years.
Sequence
3T, T2‐weighted (T2WI) and apparent diffusion coefficient (ADC) maps derived from diffusion‐weighted sequences.
Assessment
PCa regions of interest (ROIs) on T2WI were annotated by two experienced radiologists. Radiomic features from bpMRI (T2WI and ADC maps) were extracted from the ROIs. A machine‐learning classifier (CBCR) was trained with the best discriminating set of radiomic features to predict BCR (pBCR).
Statistical Tests
Wilcoxon rank‐sum tests with P < 0.05 were considered statistically significant. Differences in BCR‐free survival at 3 years using pBCR was assessed using the Kaplan–Meier method and compared with Gleason Score (GS), PSA, and PIRADS‐v2.
Results
Distribution statistics of co‐occurrence of local anisotropic gradient orientation (CoLlAGe) and Haralick features from T2WI and ADC were associated with BCR (P < 0.05) on D1. CBCR predictions resulted in a mean AUC = 0.84 on D1 and AUC = 0.73 on D2. A significant difference in BCR‐free survival between the predicted classes (BCR + and BCR–) was observed (P = 0.02) on D2 compared to those obtained from GS (P = 0.8), PSA (P = 0.93) and PIRADS‐v2 (P = 0.23).
Data Conclusion
Radiomic features from pretreatment bpMRI can be predictive of PCa BCR after therapy and may help identify men who would benefit from adjuvant therapy.
Level of Evidence: 4
Technical Efficacy: Stage 5
J. Magn. Reson. Imaging 2018;48:1626–1636
SummaryBackgroundLate radiation cystitis is an adverse effect of cancer treatment with radiotherapy in the pelvic region. Symptoms of late radiation cystitis can be assessed with the Expanded ...Prostate Index Composite Score (EPIC). Previous reports indicate that hyperbaric oxygen therapy reduces symptoms from late radiation cystitis, but the evidence is predominantly based on non-randomised and retrospective studies. We aimed to assess whether hyperbaric oxygen therapy would mitigate symptoms of late radiation cystitis. MethodsWe did a randomised, controlled, phase 2–3 trial (RICH-ART Radiation Induced Cystitis treated with Hyperbaric oxygen—A Randomised controlled Trial) at five Nordic university hospitals. All patients aged 18–80 years, with pelvic radiotherapy completed at least 6 months previously, a score of less than 80 in the urinary domain of the Expanded Prostate Index Composite Score (EPIC), and referred to participating hyperbaric clinics due to symptoms of late radiation cystitis, were eligible for inclusion. Exclusion criteria were ongoing bleeding requiring blood transfusion exceeding 500 mL in the past 4 weeks, permanent urinary catheter, bladder capacity less than 100 mL, fistula in the urinary bladder, previous treatment with hyperbaric oxygen therapy for late radiation injuries, and contraindications to hyperbaric oxygen therapy. After computer-generated 1:1 randomisation with block sizes of four for each stratification group (sex, time from radiotherapy to inclusion, and previous invasive surgery in the pelvic area), patients received hyperbaric oxygen therapy (30–40 sessions, 100% oxygen, breathed at a pressure of 240–250 kPa, for 80–90 min daily) or standard care with no restrictions for other medications or interventions. No masking was applied. The primary outcome was change in patient-perceived urinary symptoms assessed with EPIC from inclusion to follow-up at visit 4 (6–8 months later), measured as absolute change in EPIC urinary total score. RICH-ART closed enrolment on Dec 31, 2017; the last follow-up data will be compiled in 2023. RICH-ART is registered with ClinicalTrials.gov, number NCT01659723, and with the European Medicines Agency, number EudraCT 2012-001381-15. FindingsOf 3 patients screened between May 9, 2012, and Dec 20, 2017, 87 patients were enrolled and randomly assigned to either hyperbaric oxygen therapy (n=42) or standard care (n=45). After excluding eight patients who withdrew consent directly after randomisation (one in the hyperbaric oxygen therapy group and seven in the standard care group), 79 were included in the intention-to-treat analyses (n=41 in the hyperbaric oxygen therapy group, n=38 in the standard care group). Median time from randomisation to visit 4 was 234 days (IQR 210–262) in the hyperbaric oxygen therapy group and 217 days (195–237) in the standard care group. The difference between change in group mean of EPIC urinary total score at visit 4 was 10·1 points (95% CI 2·2–18·1; p=0·013; 17·8 points SD 18·4 in the hyperbaric oxygen therapy group vs 7·7 points 15·5 in the standard care group). 17 (41%) of 41 patients in the hyperbaric oxygen therapy group experienced transient grade 1–2 adverse events, related to sight and hearing, during the period of hyperbaric oxygen therapy. InterpretationOur results suggest that hyperbaric oxygen therapy relieves symptoms of late radiation cystitis. We conclude that hyperbaric oxygen therapy is a safe and well tolerated treatment. FundingThe regional research fund of Region Västra Götaland, Sweden, the regional Health Technology Assessment Centre at Sahlgrenska University Hospital, Sweden, and Lions Cancer Research Fund of Western Sweden.
Transurethral resection of the prostate (TURP) is the standard surgical treatment for benign prostate enlargement (BPE). Photoselective vaporization of the prostate (PVP) is an alternative, but there ...is limited real-life evidence of PVP risks.
To compare short- and long-term risks of PVP to those of TURP in the treatment of BPE.
Consecutive patients who underwent elective PVP or TURP between 2006 and 2018 in 20 hospitals in Finland were retrospectively studied using a combination of national registries (n = 27,408; mean age 71 years). Short-term risks were postoperative mortality, major adverse cardiovascular events (MACE), and reoperations for bleeding. Long-term risks were reoperations for BPE or any urethral operations within 12 years. Differences between treatment groups were balanced by inverse probability of treatment weighting. Risks were analyzed using the Kaplan-Meier method and Cox regression.
There were no differences in postoperative mortality or MACE between the study groups. Reoperations for bleeding were less frequent after PVP (0.9%, HR: 0.72, p = 0.042). Bleeding was more likely in patients with atrial fibrillation (number needed to treat NNT for PVP vs TURP: 61). Cumulative incidence for reoperation was higher after PVP (23.5%) than after TURP in long-term follow-up (17.8%; HR: 1.20, p < 0.0001, NNT: −31.7).
PVP is associated with lower postoperative bleeding risk but higher long-term reoperation risk than TURP. Patients with high bleeding risk and a low likelihood of needing reoperation appear most suitable for laser vaporization.
KEY MESSAGE
PVP is associated with lower postoperative bleeding risk but higher long-term reoperation risk than TURP. PVP appears an attractive treatment option, especially for patients with high bleeding risk and a low likelihood of needing a reoperation.
After surgery of localized renal cell carcinoma, over 20% of the patients will develop distant metastases. Our aim was to develop an easy-to-use prognostic model for predicting metastasis-free ...survival after radical or partial nephrectomy of localized clear cell RCC. Model training was performed on 196 patients. Right-censored metastasis-free survival was analysed using LASSO-regularized Cox regression, which identified three key prediction features. The model was validated in an external cohort of 714 patients. 55 (28%) and 134 (19%) patients developed distant metastases during the median postoperative follow-up of 6.3 years (interquartile range 3.4-8.6) and 5.4 years (4.0-7.6) in the training and validation cohort, respectively. Patients were stratified into clinically meaningful risk categories using only three features: tumor size, tumor grade and microvascular invasion, and a representative nomogram and a visual prediction surface were constructed using these features in Cox proportional hazards model. Concordance indices in the training and validation cohorts were 0.755 ± 0.029 and 0.836 ± 0.015 for our novel model, which were comparable to the C-indices of the original Leibovich prediction model (0.734 ± 0.035 and 0.848 ± 0.017, respectively). Thus, the presented model retains high accuracy while requiring only three features that are routinely collected and widely available.
Objectives
To evaluate short-term test-retest repeatability of a deep learning architecture (U-Net) in slice- and lesion-level detection and segmentation of clinically significant prostate cancer ...(csPCa: Gleason grade group > 1) using diffusion-weighted imaging fitted with monoexponential function, ADC
m
.
Methods
One hundred twelve patients with prostate cancer (PCa) underwent 2 prostate MRI examinations on the same day. PCa areas were annotated using whole mount prostatectomy sections. Two U-Net-based convolutional neural networks were trained on three different ADC
m
b
value settings for (a) slice- and (b) lesion-level detection and (c) segmentation of csPCa. Short-term test-retest repeatability was estimated using intra-class correlation coefficient (ICC(3,1)), proportionate agreement, and dice similarity coefficient (DSC). A 3-fold cross-validation was performed on training set (
N
= 78 patients) and evaluated for performance and repeatability on testing data (
N
= 34 patients).
Results
For the three ADC
m
b
value settings, repeatability of mean ADC
m
of csPCa lesions was ICC(3,1) = 0.86–0.98. Two CNNs with U-Net-based architecture demonstrated ICC(3,1) in the range of 0.80–0.83, agreement of 66–72%, and DSC of 0.68–0.72 for slice- and lesion-level detection and segmentation of csPCa. Bland-Altman plots suggest that there is no systematic bias in agreement between inter-scan ground truth segmentation repeatability and segmentation repeatability of the networks.
Conclusions
For the three ADC
m
b
value settings, two CNNs with U-Net-based architecture were repeatable for the problem of detection of csPCa at the slice-level. The network repeatability in segmenting csPCa lesions is affected by inter-scan variability and ground truth segmentation repeatability and may thus improve with better inter-scan reproducibility.
Key Points
•
For the three ADC
m
b value settings, two CNNs with U-Net-based architecture were repeatable for the problem of detection of csPCa at the slice-level.
•
The network repeatability in segmenting csPCa lesions is affected by inter-scan variability and ground truth segmentation repeatability and may thus improve with better inter-scan reproducibility.
Magnetic resonance imaging (MRI) combined with targeted biopsy (TB) is increasingly used in men with clinically suspected prostate cancer (PCa), but the long acquisition times, high costs, and ...inter-center/reader variability of routine multiparametric prostate MRI limit its wider adoption.
The aim was to validate a previously developed unique MRI acquisition and reporting protocol, IMPROD biparametric MRI (bpMRI) (NCT01864135), in men with a clinical suspicion of PCa in a multi-institutional trial (NCT02241122). IMPROD bpMRI has average acquisition time of 15 minutes (no endorectal coil, no intravenous contrast use) and consists of T2-weighted imaging and 3 separate diffusion-weighed imaging acquisitions. Between February 1, 2015, and March 31, 2017, 364 men with a clinical suspicion of PCa were enrolled at 4 institutions in Finland. Men with an equivocal to high suspicion (IMPROD bpMRI Likert score 3-5) of PCa had 2 TBs of up to 2 lesions followed by a systematic biopsy (SB). Men with a low to very low suspicion (IMPROD bpMRI Likert score 1-2) had only SB. All data and protocols are freely available. The primary outcome of the trial was diagnostic accuracy-including overall accuracy, sensitivity, specificity, negative predictive value (NPV), and positive predictive value-of IMPROD bpMRI for clinically significant PCa (SPCa), which was defined as a Gleason score ≥ 3 + 4 (Gleason grade group 2 or higher). In total, 338 (338/364, 93%) prospectively enrolled men completed the trial. The accuracy and NPV of IMPROD bpMRI for SPCa were 70% (113/161) and 95% (71/75) (95% CI 87%-98%), respectively. Restricting the biopsy to men with equivocal to highly suspicious IMPROD bpMRI findings would have resulted in a 22% (75/338) reduction in the number of men undergoing biopsy while missing 4 (3%, 4/146) men with SPCa. The main limitation is uncertainty about the true PCa prevalence in the study cohort, since some of the men may have PCa despite having negative biopsy findings.
IMPROD bpMRI demonstrated a high NPV for SPCa in men with a clinical suspicion of PCa in this prospective multi-institutional clinical trial.
ClinicalTrials.gov NCT02241122.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Distinguishing aggressive prostate cancer from indolent disease improves personalized treatment. Although only few genetic variants are known to predispose to aggressive prostate cancer, synergistic ...interactions of
G84E high-risk prostate cancer susceptibility mutation with other genetic loci remain unknown. The purpose of this study was to examine the interplay of
rs138213197 (G84E) and
rs2278911 (R229Q) germline variants on prostate cancer risk.
Genotyping was done in Finnish discovery cohort (
= 2,738) and validated in Swedish (
= 3,132) and independent Finnish (
= 1,155) prostate cancer cohorts. Expression pattern analysis was followed by functional studies in prostate cancer cell models.
Interplay of
(G84E) and
(R229Q) variants results in highest observed inherited prostate cancer risk (OR, 21.1;
= 0.000024). In addition, this synergism indicates a significant association of
T and
T dual carriers with elevated risk for high Gleason score (OR, 2.3;
= 0.025) and worse prostate cancer-specific life expectancy (HR, 3.9;
= 0.048), and it is linked with high PSA at diagnosis (OR, 3.30;
= 0.028). Furthermore, combined high expression of
correlates with earlier biochemical recurrence. Finally, functional experiments showed that ectopic expression of variants stimulates prostate cancer cell growth and migration. In addition, we observed strong chromatin binding of HOXB13 at
locus and revealed that
functionally promotes
transcription. The study is limited to retrospective Nordic cohorts.
Simultaneous presence of
T and
T alleles confers for high prostate cancer risk and aggressiveness of disease, earlier biochemical relapse, and lower disease-specific life expectancy. HOXB13 protein binds to
gene and functionally promotes
transcription.
Purpose
We aimed to develop and externally validate a nomogram based on MRI volumetric parameters and clinical information for deciding when SBx should be performed in addition to TBx in man with ...suspicious prostate MRI.
Materials and methods
Retrospective analyses of single (IMPROD, NCT01864135) and multi-institution (MULTI-IMPROD, NCT02241122) clinical trials. All men underwent a unique rapid biparametric magnetic resonance imaging (IMPROD bpMRI) consisting of T2-weighted imaging and three separate DWI acquisitions. Men with IMPROD bpMRI Likert scores of 3–5 were included. Logistic regression models were developed using IMPROD trial (
n
= 122) and validated using MULTI-IMPROD trial (
n
= 262) data. The model’s performance was evaluated in the terms of PCa detection with Gleason Grade Group 1 (clinically insignificant prostate cancer, iPCa) and > 1 (clinically significant prostate cancer, csPCa). Net benefits and decision curve analyses (DCA) were compared. Combined biopsies were used for reference.
Results
The developed nomogram included age, PSA, prostate volume, MRI suspicion score (IMPROD bpMRI Likert or PIRADsv2.1 score), MRI-suspicion lesion volume percentage, and lesion location. All these variables were significant predictors of csPCa in SBx in multivariable analysis. In the validation cohort (
n
= 262) using different nomogram cutoffs, 19–43% of men would have avoided SBx while missing 1–4% of csPCa and avoiding detection of 9–20% of iPCa. Similar performance was found for nomograms using IMPROD bpMRI Likert score or v2.1.
Conclusions
The developed nomogram demonstrated potential to select men with a clinical suspicion of PCa who would benefit from performing SBx in addition to TBx. Public access to the nomogram is provided at:
https://petiv.utu.fi/multiimprod/
.
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