Can whole-body MRI replace CT in management of metastatic testicular cancer? A prospective, non-inferiority study.

PURPOSE: Concerns of imaging-related radiation exposure in young patients with high survival rates have increased the use of magnetic resonance imaging (MRI) in testicular cancer (TC) stage I. However, computed tomography (CT) is still preferred for metastatic TC. The purpose of this study was to compare whole-body MRI incl. diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) with contrast-enhanced, thoracoabdominal CT in metastatic TC. METHODS: A prospective, non-inferiority study of 84 consecutive patients (median age 33 years) with newly diagnosed metastatic TC (February 2018-January 2021). Patients had both MRI and CT before and after treatment. Anonymised images were reviewed by experienced radiologists. Lesion malignancy was evaluated on a Likert scale (1 benign-4 malignant). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were calculated on patient and lesion level. The primary outcome was demonstrating non-inferiority regarding sensitivity of MRI compared to CT. The non-inferiority margin was set at 5%. ROC curves and interobserver agreement were calculated. RESULTS: On patient level, MRI had 98% sensitivity and 75% specificity compared to CT. On lesion level within each modality, MRI had 99% sensitivity and 78% specificity, whereas CT had 98% sensitivity and 88% specificity. MRI sensitivity was non-inferior to CT (difference 0.57% (95% CI - 1.4-2.5%)). The interobserver agreement was substantial between CT and MRI. CONCLUSION: MRI with DWIBS was non-inferior to contrast-enhanced CT in detecting metastatic TC disease. TRIAL REGISTRATION: www. CLINICALTRIALS: gov NCT03436901, finished July 1st 2021.

Telehealth in Multidisciplinary Target Delineation for Radiotherapy During the COVID-19 Pandemic. A Review and a Case.

Like all other medical specialties, radiotherapy has been deeply influenced by the COVID-19 pandemic. The pandemic has had severe influence on the entire patient trajectory in oncology, from diagnosis to treatment and follow-up. Many examples of how to deal with patient and staff safety, shortness of staff and other resources and the quest to continue high-quality, evidence-based treatment have been presented. The use of telemedicine and telehealth is frequently presented as a part of the solution to overcome these challenges. Some of the available presented solutions will only apply in an acute, local setting, whereas others might inspire the community to improve quality and cost-effectiveness of radiotherapy as well as knowledge sharing in the future. Some of the unresolved issues in many of the available technical solutions are related to data security and public regulation, for example, GDPR (General Data Protection Regulation) in the EU and HIPAA compliance (Health Insurance Portability and Accountability Act) in the USA. Using a solution that involves a supplier's server in a non-EU country is problematic within the EU. In this paper we shortly review the influence of COVID-19 on radiotherapy. We describe some of the possible solutions for telehealth in target delineation - a crucial part of high-quality radiotherapy, which often requires multidisciplinary effort, hands-on corporation, and high-quality multimodal imaging. Hereafter, our own technical solution will be presented as a case.

Multi-band whole-body diffusion-weighted imaging with inversion recovery fat saturation: Effects of respiratory compensation.

PURPOSE: To prospectively compare artefacts and image quality in testicular stage I cancer patients using different combinations of breathing schemes and Multi-band (MB) in whole-body DWIBS at 1.5 T.Diffusion-Weighted whole-body Imaging with Background body signal Suppression (DWIBS) using inversion recovery (IR) fat saturation is a cornerstone in oncologic whole-body MRI, but implementation is restrained by long acquisition times. The new Multi-Band (MB) technique reduces scan time which can be reinvested in respiratory compensation. METHODS: Thirty testicular cancer stage I patients were included. Three variations of whole-body DWIBS were tested: Standard free Breathing (FB)-DWIBS, FB-MB-DWIBS and Respiratory triggered (RT)-MB-DWIBS. Artefacts and image quality of b = 800 s/mm2 images were evaluated using a Likert scale. No pathology was revealed. SNR was calculated in a healthy volunteer. RESULTS: RT-MB-DWIBS was rated significantly better than FB-DWIBS in the thorax (p < 0.001) and abdomen (p < 0.001), but not in the pelvis (p = 0.569). FB-MB-DWIBS was ranked significantly lower than both FB-DWIBS (p < 0.001) and RT-MB-DWIBS (p < 0.001) at all locations. However, FB-MB-DWIBS was scanned in half the time without being less than "satisfactory". Few artefacts were encountered. SNR was similar for low-intensity tissues, but the SNR in high-intensity and respiratory-prone tissue (spleen) was slightly lower for FB-DWIBS than the other sequences. CONCLUSION: Images produced by the sequences were similar. MB enables the use of respiratory trigger or can be used to produce very fast free-breathing DWI with acceptable image quality.

Comparison of contrast-enhanced CT, dual-layer detector spectral CT, and whole-body MRI in suspected metastatic breast cancer: a prospective diagnostic accuracy study.

OBJECTIVES: To compare diagnostic accuracy of contrast-enhanced CT, dual-layer detector spectral CT (DL-CT), and whole-body MRI (WB-MRI) for diagnosing metastatic breast cancer. METHODS: One hundred eighty-two biopsy-verified breast cancer patients suspected of metastatic disease prospectively underwent contrast-enhanced DL-CT and WB-MRI. Two radiologists read the CT examinations with and without spectral data in consensus with 3-month washout between readings. Two other radiologists read the WB-MRI examinations in consensus. Lymph nodes, visceral lesions, and bone lesions were assessed. Readers were blinded to other test results. Reference standard was histopathology, previous or follow-up imaging, and clinical follow-up. RESULTS: Per-lesion AUC was 0.80, 0.84, and 0.82 (CT, DL-CT, and WB-MRI, respectively). DL-CT showed significantly higher AUC than CT (p = 0.001) and WB-MRI (p = 0.02). Sensitivity and specificity of CT, DL-CT, and WB-MRI were 0.66 and 0.94, 0.75 and 0.95, and 0.65 and 0.98, respectively. DL-CT significantly improved sensitivity compared to CT (p < 0.0001) and WB-MRI (p = 0.002). Per-patient AUC was 0.85, 0.90, and 0.92 (CT, DL-CT, and WB-MRI, respectively). DL-CT and WB-MRI had significantly higher AUC than CT (p = 0.04 and p = 0.03). DL-CT significantly increased sensitivity compared to CT (0.89 vs. 0.79, p = 0.04). WB-MRI had significantly higher specificity than CT (0.84 vs. 0.96, p = 0.001) and DL-CT (0.87 vs. 0.96, p = 0.02). CONCLUSIONS: DL-CT showed significantly higher per-lesion diagnostic performance and sensitivity than CT and WB-MRI. On a per-patient basis, DL-CT and WB-MRI had equal diagnostic performance superior to CT. KEY POINTS: • Spectral CT has higher diagnostic performance for diagnosing breast cancer metastases compared to conventional CT and whole-body MRI on a per-lesion basis. • Spectral CT and whole-body MRI are superior to conventional CT for diagnosing patients with metastatic breast cancer. • Whole-body MRI is superior to conventional CT and spectral CT for diagnosing bone metastases.

Anatomical considerations for obturator nerve block with fascia iliaca compartment block.

This report reviews the topographical and functional anatomy relevant for assessing whether or not the obturator nerve (ON) can be anesthetized using a fascia iliaca compartment (FIC) block. The ON does not cross the FIC. This means that the ON would only be blocked by an FIC block if the injectate spreads to the ON outside of the FIC. Such a phenomena would require the creation of one or more artificial passageways to the ON in the retro-psoas compartment or the retroperitoneal compartment by disrupting the normal anatomical integrity of the FI. Due to this requirement for an artificial pathway, an FIC block probably does not block the ON.

Breast cancer: comparison of quantitative dual-layer spectral CT and axillary ultrasonography for preoperative diagnosis of metastatic axillary lymph nodes.

BACKGROUND: Our aim was to compare the diagnostic performance of quantitative dual-layer spectral computed tomography (DLSCT) and axillary ultrasound (US) for diagnosing lymph node metastases in breast cancer patients. METHODS: DLSCT and axillary US were prospectively performed in 70 needle biopsy-verified breast cancer patients. Histopathology and imaging data were available for evaluation in 36 axillae from 34 patients. In each patient, ipsilateral, contralateral, and inguinal lymph nodes (LNs) were semiautomatically segmented, and iodine density, spectral slope, Z effective, virtual non-contrast (VNC), conventional CT HU values, and Δ contrast enhancement (ΔCE, conventional CT HU minus VNC) were measured. Using histopathology as reference, the diagnostic performance of DLSCT and axillary US was compared. RESULTS: Of 36 axillae, 23 had metastatic lymph nodes. Compared with non-metastatic LNs, metastatic LNs had significantly different iodine density (p = 0.021), spectral slope (p < 0.001), Z effective (p < 0.001), conventional CT HU values (p < 0.01), and ΔCE (p < 0.01). All DLSCT parameters were significantly different between arterial phase and portal-venous phase (p < 0.001) except for VNC (p = 0.092). ΔCE had the highest diagnostic performance (sensitivity 0.79, specificity 0.92, positive predictive value 0.95, negative predictive value 0.69) with a significantly increased sensitivity compared with conventional CT HU (p = 0.027). There were no significant differences between ΔCE and axillary US for sensitivity (p = 1.000) or specificity (p = 0.320). CONCLUSIONS: DLSCT is a promising quantitative technique for evaluating LN metastases and could potentially reduce the need for sentinel LN biopsy.

Fat fractions from high-resolution 3D radial Dixon MRI for predicting metastatic axillary lymph nodes in breast cancer patients.

PURPOSE: To assess diagnostic performance of fat fractions (FF) from high-resolution 3D radial Dixon MRI for differentiating metastatic and non-metastatic axillary lymph nodes in breast cancer patients. METHOD: High-resolution 3D radial Dixon MRI was prospectively performed on 1.5 T in 70 biopsy-verified breast cancer patients. 35 patients were available for analysis with histopathologic and imaging data. FF images were calculated as fat / in-phase. Two radiologists measured lymph node FF and assessed morphological features in one ipsilateral and one contralateral lymph node in consensus. Diagnostic performance of lymph node FF and morphological criteria were compared using histopathology as reference. RESULTS: 22 patients had metastatic axillary lymph nodes. Mean lymph node FF were 0.20 ±â€¯0.073, 0.31 ±â€¯0.079, and 0.34 ±â€¯0.15 (metastatic, non-metastatic ipsi- and non-metastatic contralateral lymph nodes, respectively). Metastatic lymph node FF were significantly lower than non-metastatic ipsi- (p <  0.001) and contralateral lymph nodes (p <  0.001). Area under the receiver operating characteristics curve for lymph node FF was 0.80 compared to 0.76 for morphological criteria (p =  0.29). Lymph node FF yielded sensitivity 0.91, specificity 0.69, positive predictive value (PPV) 0.83, and negative predictive value (NPV) 0.82, while morphological criteria yielded sensitivity 0.91, specificity 0.62, PPV 0.80, and NPV 0.80 (p =  0.71). Combining lymph node FF and morphological criteria increased diagnostic performance with sensitivity 1.00, specificity 0.67, PPV 0.86, NPV 1.00, and AUC 0.83. CONCLUSIONS: Lymph node FF from high-resolution 3D Dixon images are a promising quantitative indicator of metastases in axillary lymph nodes.

Simultaneous multislice diffusion-weighted imaging with short tau inversion recovery fat suppression in bone-metastasizing breast cancer.

PURPOSE: To compare image quality and ADC values of simultaneous multislice diffusion-weighted imaging (mb-DWI) with that of conventional DWI (c-DWI) using short tau inversion recovery fat saturation (STIR) in women with bone-metastasizing breast cancer. METHOD: c-DWI and mb-DWI were acquired at 1.5 T in 23 breast cancer patients from skull base to mid thighs. mb-DWI was compared to c-DWI in terms of subjective image quality, artefacts and bone metastasis lesion conspicuity assessed on a 5-point Likert scale. ADC values of different organs as well as bone metastasis ADC values were compared between c-DWI and mb-DWI. RESULTS: mb-DWI reduced scan time by 48 % compared with c-DWI (1 min 58 s vs. 3 min 45 s per station). mb-DWI provided similar subjective image quality (3.8 vs. 3.7, p = 0.70), number of artefacts (50 vs. 56), severity of these (4.6 vs. 4.7, p = 0.11), and lesion conspicuity (4.2 vs. 4.4, p = 0.31) compared to c-DWI. mb-DWI showed lower mean ADC values in liver (0.5 × 10-3 mm2/s vs. 0.7 × 10-3 mm2/s, p = 0.002) and erector spine muscle (1.3 × 10-3 mm2/s vs. 1.5 × 10-3 mm2/s, p < 0.001). Bone metastasis ADC values from mb-DWI were 6.4 % lower than c-DWI (95 % confidence interval: 5.4%-7.4%, p < 0.001). CONCLUSIONS: mb-DWI provides similar subjective image quality to c-DWI with the same level of artefacts. Although bone metastasis ADC values were lower, mb-DWI can substantially reduce scan times of whole-body DWI in women with bone-metastasizing breast cancer.

Ten years of experience with MRI follow-up of testicular cancer stage I: a retrospective study and an MRI protocol with DWI.

INTRODUCTION: Patients with testicular cancer (TC) are mainly young and survival rates are high. MRI has several times been proposed to replace CT in follow-up of this patient group to reduce image-related radiation exposure. However, current evidence is scarce for the use of MRI in this context. AIMS: First, to retrospectively evaluate the ability of MRI of the retroperitoneum and pelvis to detect relapse in patients with TC stage I. Second, to present a relevant MRI protocol of the retroperitoneum and pelvis with diffusion weighted imaging (DWI). MATERIAL AND METHODS: A retrospective analysis of written radiology reports compared to clinical data from clinical practice from 2010 to 2018. The cohort consists of 2487 MRIs of the retroperitoneum and pelvis in 759 patients with TC stage I (524 seminoma (69.0%), 235 non-seminoma (31.0%)), including 102 patients (13.4%) with confirmed relapse. Confirmed relapse was defined when treatment was initiated for metastatic TC. RESULTS: Ninety-five patients had a relapse in the MRI scan field during follow-up. MRI of the retroperitoneum and pelvis showed a high sensitivity of 93.8% and a high specificity of 97.4% for detecting TC relapse. The sensitivity for detecting relapse ≥10 mm in short axis lymph node diameter was 100%. The negative predictive value was 99.7%, the positive predictive value was 59.9% and the accuracy was 97.3%. CONCLUSIONS: MRI of the retroperitoneum and pelvis constitutes a safe alternative to CT in follow-up of patients with TC stage I with both a high sensitivity and a high specificity. We present a robust MRI protocol with DWI and estimate that MRI follow-up of TC stage I can be easily implemented in most modern radiology departments. Registration: Conducted with permission from the Danish Data Protection Agency (1-16-02-323-16) and the Danish Health Authority.

Use of patient outcome endpoints to identify the best functional CT imaging parameters in metastatic renal cell carcinoma patients.

OBJECTIVE: To use the patient outcome endpoints overall survival and progression-free survival to evaluate functional parameters derived from dynamic contrast-enhanced CT. METHODS: 69 patients with metastatic renal cell carcinoma had dynamic contrast-enhanced CT scans at baseline and after 5 and 10 weeks of treatment. Blood volume, blood flow and standardized perfusion values were calculated using deconvolution (BVdeconv, BFdeconv and SPVdeconv), blood flow and standardized perfusion values using maximum slope (BFmax and SPVmax) and blood volume and permeability surface area product using the Patlak model (BVpatlak and PS). Histogram data for each were extracted and associated to patient outcomes. Correlations and agreements were also assessed. RESULTS: The strongest associations were observed between patient outcome and medians and modes for BVdeconv, BVpatlak and BFdeconv at baseline and during the early ontreatment period (p < 0.05 for all). For the relative changes in median and mode between baseline and weeks 5 and 10, PS seemed to have opposite associations dependent on treatment. Interobserver correlations were excellent (r ≥ 0.9, p < 0.001) with good agreement for BFdeconv, BFmax, SPVdeconv and SPVmax and moderate to good (0.5 < r < 0.7, p < 0.001) for BVdeconv and BVpatlak. Medians had a better reproducibility than modes. CONCLUSION: Patient outcome was used to identify the best functional imaging parameters in patients with metastatic renal cell carcinoma. Taking patient outcome and reproducibility into account, BVdeconv, BVpatlak and BFdeconv provide the most clinically meaningful information, whereas PS seems to be treatment dependent. Standardization of acquisition protocols and post-processing software is necessary for future clinical utilization. Advances in knowledge: Taking patient outcome and reproducibility into account, BVdeconv, BVpatlak and BFdeconv provide the most clinically meaningful information. PS seems to be treatment dependent.

Real-Time Ultrasound/MRI Fusion for Suprasacral Parallel Shift Approach to Lumbosacral Plexus Blockade and Analysis of Injectate Spread: An Exploratory Randomized Controlled Trial.

Fused real-time ultrasound and magnetic resonance imaging (MRI) may be used to improve the accuracy of advanced image guided procedures. However, its use in regional anesthesia is practically nonexistent. In this randomized controlled crossover trial, we aim to explore effectiveness, procedure-related outcomes, injectate spread analyzed by MRI, and safety of ultrasound/MRI fusion versus ultrasound guided Suprasacral Parallel Shift (SSPS) technique for lumbosacral plexus blockade. Twenty-six healthy subjects aged 21-36 years received two SSPS blocks (20 mL 2% lidocaine-epinephrine [1 : 200,000] added 1 mL diluted contrast) guided by ultrasound/MRI fusion versus ultrasound. Number (proportion) of subjects with motor blockade of the femoral and obturator nerves and the lumbosacral trunk was equal (ultrasound/MRI, 23/26 [88%]; ultrasound, 23/26 [88%]; p = 1.00). Median (interquartile range) preparation and procedure times (s) were longer for the ultrasound/MRI fusion guided technique (686 [552-1023] versus 196 [167-228], p < 0.001 and 333 [254-439] versus 216 [176-294], p = 0.001). Both techniques produced perineural spread and corresponding sensory analgesia from L2 to S1. Epidural spread and lidocaine pharmacokinetics were similar. Different compartmentalized patterns of injectate spread were observed. Ultrasound/MRI fusion guided SSPS was equally effective and safe but required prolonged time, compared to ultrasound guided SSPS. This trial is registered with EudraCT (2013-004013-41) and ClinicalTrials.gov (NCT02593370).

Risk Factors for Pelvic Insufficiency Fractures in Locally Advanced Cervical Cancer Following Intensity Modulated Radiation Therapy.

PURPOSE: To investigate the incidence of and risk factors for pelvic insufficiency fracture (PIF) after definitive chemoradiation therapy for locally advanced cervical cancer (LACC). METHODS AND MATERIALS: We analyzed 101 patients with LACC treated from 2008-2014. Patients received weekly cisplatin and underwent external beam radiation therapy with 45 Gy in 25 fractions (node-negative patients) or 50 Gy in 25 fractions with a simultaneous integrated boost of 60 Gy in 30 fractions (node-positive patients). Pulsed dose rate magnetic resonance imaging guided adaptive brachytherapy was given in addition. Follow-up magnetic resonance imaging was performed routinely at 3 and 12 months after the end of treatment or based on clinical indication. PIF was defined as a fracture line with or without sclerotic changes in the pelvic bones. D50% and V55Gy were calculated for the os sacrum and jointly for the os ileum and pubis. Patient- and treatment-related factors including dose were analyzed for correlation with PIF. RESULTS: The median follow-up period was 25 months. The median age was 50 years. In 20 patients (20%), a median of 2 PIFs (range, 1-3 PIFs) were diagnosed; half were asymptomatic. The majority of the fractures were located in the sacrum (77%). Age was a significant risk factor (P<.001), and the incidence of PIF was 4% and 37% in patients aged ≤50 years and patients aged >50 years, respectively. Sacrum D50% was a significant risk factor in patients aged >50 years (P=.04), whereas V55Gy of the sacrum and V55Gy of the pelvic bones were insignificant (P=.33 and P=.18, respectively). A dose-effect curve for sacrum D50% in patients aged >50 years showed that reduction of sacrum D50% from 40 GyEQD2 to 35 GyEQD2 reduces PIF risk from 45% to 22%. CONCLUSIONS: PIF is common after treatment of LACC and is mainly seen in patients aged >50 years. Our data indicate that PIFs are not related to lymph node boosts but rather to dose and volume associated with irradiation of the elective pelvic target. Reducing the prescribed elective dose from 50 to 45 Gy may reduce the risk of PIF considerably.

Comparison of four MRI protocols for detection of extrahepatic colorectal cancer metastases.

PURPOSE: To compare three magnetic resonance imaging (MRI) protocols containing diffusion-weighted imaging with background suppression (DWIBS) and one traditional protocol for detecting extrahepatic colorectal cancer metastases. MATERIALS AND METHODS: Thirty patients with extrahepatic colorectal cancer metastases were scanned in three stations from the skull base to the upper thighs using a 1.5T MRI system with six different MRI sequences; transverse and coronal T2 -weighted (T2 W) turbo spin-echo (TSE), coronal short tau inversion recovery (STIR), 3D T1 W TSE, DWIBS, and a contrast-enhanced T1 W 3D gradient echo (GRE) sequence. The six sequences were used to build four hypothetical MRI interpretive sets which were read by two readers in consensus, blinded to prior imaging. Lesions were categorized into 13 anatomic regions. Fluorodeoxyglucose / positron emission tomography / computed tomography (FDG-PET/CT) read with full access to prior imaging and clinical records was used as the reference standard. Sensitivity, specificity, and false discovery rate (FDR) were calculated as appropriate and receiver operating characteristic (ROC) curves were constructed. RESULTS: In all, 177 malignant lesions were detected by FDG-PET/CT and distributed in 92 out of 390 scanned anatomic regions. The sensitivity was statistically higher in two out of three sets incorporating DWIBS on a per-lesion basis (66.7%, 63.3%, and 66.7% vs. 57.6%) (P = 0.01, P = 0.11, and P = 0.01, respectively) and in all sets incorporating DWIBS on a per-region basis (75.0%, 75.0%, and 77.2 vs. 66.3%) (P = 0.04, P = 0.04, and P = 0.01, respectively). There was no difference in specificity, FDR, or AUCROC . There was no difference between sets containing DWIBS irrespective of the use of a contrast-enhanced sequence. CONCLUSION: MRI sets containing DWIBS had superior sensitivity. This sensitivity was retained when omitting a contrast-enhanced sequence. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1619-1630.

Dynamic Contrast-Enhanced Computed Tomography-Derived Blood Volume and Blood Flow Correlate With Patient Outcome in Metastatic Renal Cell Carcinoma.

OBJECTIVES: The aim was to explore the potential for using dynamic contrast-enhanced computed tomography as a noninvasive functional imaging biomarker before and during the early treatment of metastatic renal cell carcinoma (mRCC). MATERIALS AND METHODS: Dynamic contrast-enhanced computed tomography scans were performed at baseline and after 5 and 10 weeks' treatment in 69 prospectively included mRCC patients receiving treatment with interferon alpha and interleukin 2 (n = 26); interferon alpha, interleukin 2, and bevacizumab (n = 24); sunitinib (n = 7); pazopanib (n = 5); or temsirolimus (n = 7). Using a prototype software program (Advanced Perfusion and Permeability Application, Philips Healthcare, Best, the Netherlands), blood volume (BV), blood flow (BF), and permeability surface area product (PS) were calculated for each tumor at baseline, week 5, and week 10. These parameters as well as relative changes between baseline and weeks 5 and 10 were tested for associations with progression-free survival (PFS) and overall survival (OS) using Kaplan-Meier curves and log-rank tests. RESULTS: Using the 25th percentile as the cutoff, baseline BV for all patients independent of subsequent treatment was statistically significantly associated with PFS (10.8 vs 5.3 months, P = 0.007) and OS (35.2 vs 13.3 months, P = 0.001), and baseline BF was significantly associated with OS (31.7 vs 14.6 months, P = 0.024) with high values for both parameters being associated with significantly longer PFS and OS. Baseline PS was not associated with PFS or OS.In patients treated with angiogenesis inhibitors (bevacizumab, sunitinib, pazopanib, or temsirolimus), the relative change in BV from baseline to week 5 using 25th percentile as the cutoff was associated with PFS (5.6 vs 24.8 months, P = 0.001) and OS (19.1 months vs not reached, P = 0.008) and from baseline to week 10 with PFS (8.1 vs 16.4 months, P = 0.014) and OS (15.5 months vs not reached, P = 0.002). The relative change in BF from baseline to week 5 using medians as the cutoff was associated with PFS (5.5 vs 14.3 months, P = 0.018) and OS (14.6 vs 31.7 months, P = 0.027). The relative change in BF from baseline to week 10 using 25th percentile as the cutoff was associated with PFS (8.3 vs 46.9 months, P = 0.011) and OS (19.1 vs 53.0 months, P = 0.006). For both parameters, the largest reductions during early treatment were associated with increased PFS and OS.In patients receiving immunotherapy only (interferon alpha and interleukin 2), relative changes in PS between baseline and weeks 5 and 10 were significantly associated with PFS with larger increases associated with longer PFS. In patients receiving angiogenesis inhibitors, the relative changes in PS between baseline and week 10 were significantly associated with PFS and OS with larger reductions associated with favorable outcomes. CONCLUSIONS: In patients with mRCC treated with angiogenesis inhibitors, the largest reductions in BV and BF between baseline and weeks 5 and 10 were associated with favorable outcomes. At baseline, the lowest BV and BF were associated with the poorest outcomes regardless of the subsequent treatment. Early reductions in PS were associated with favorable outcomes for those treated with angiogenesis inhibitors and with poor outcomes for those treated with immunotherapies.

Learning curve of MRI-based planning for high-dose-rate brachytherapy for prostate cancer.

PURPOSE: To evaluate introduction of MRI-based high-dose-rate brachytherapy (HDRBT), including procedure times, dose-volume parameters, and perioperative morbidity. METHODS AND MATERIALS: Study included 42 high-risk prostate cancer patients enrolled in a clinical protocol, offering external beam radiotherapy + two HDRBT 8.5 Gy boosts. Time was recorded for initiation of anesthesia (A), fixation of needle implant (B), end of MR imaging (C), plan approval (D), and end of HDRBT delivery (E). We defined time A-E as total procedure time, A-B as operating room time, B-C as MRI procedure time, C-D as treatment planning time, and D to E as treatment delivery time. Dose-volume parameters were retrieved from the dose planning system. Results from the first 21 patients were compared with the last 21 patients. RESULTS: Total procedure time, operating room time, MRI procedure time, and treatment planning time decreased significantly from average 7.6 to 5.3 hours (p < 0.01), 3.6 to 2.4 hours (p < 0.01), 1.6 to 0.8 hours (p < 0.01), and 2.0 to 1.3 hours (p < 0.01), respectively. HDRBT delivery time remained unchanged at 0.5 hours. Clinical target volume prostate+3mmD90 fulfilled planning aim in 92% of procedures and increased significantly from average 8.3 to 9.0 Gy (p < 0.01). Urethral D0.1 cm(3) and rectal D2 cm(3) fulfilled planning aim in 78% and 95% of procedures, respectively, and did not change significantly. Hematuria occurred in (95%), hematoma (80%), moderate to strong pain (35%), and urinary retention (5%) of procedures. CONCLUSIONS: After introduction of MRI-based HDRBT, procedure times were significantly reduced. D90 Clinical target volumeprostate+3mm fulfilled constraints in most patients and improved over time, but not at expense of an increased urethral or rectal dose.

Single photon emission computed tomography (SPECT) and SPECT/low-dose computerized tomography did not increase sensitivity or specificity compared to planar bone scintigraphy for detection of bone metastases in advanced breast cancer.

PURPOSE: To evaluate and compare the diagnostic performance of whole-body planar bone scintigraphy (WBS), single photon emission computed tomography (SPECT), SPECT/low-dose computerized tomography (SPECT/ldCT) and SPECT/contrast enhanced diagnostic CT (SPECT/cdCT) in the staging of patients with advanced breast cancer. METHODS: Seventy-eight patients with recurrence of biopsy-proven breast cancer and suspicion of disseminated disease were investigated with WBS, SPECT, SPECT/ldCT, SPECT/cdCT and MRI performed on the same day in this prospective study. Images were separately analysed in a blinded fashion by radiologists and nuclear medicine physicians regarding the presence of pathological findings. MRI served as reference standard. RESULTS: According to reference standard, 38 of 73 patients had bone metastases. The sensitivity was 87%, 87%, 79%, and 84% and specificity 63%, 71%, 63% and 83% for WBS, SPECT, SPECT/ldCT and SPECT/cdCT. A significantly increased specificity of SPECT/cdCT compared to WBS and SPECT/ldCT was found, and other parameters did not differ significantly between modalities. Additional two patients had bone metastases solely located outside the MRI scan field and seven patients had soft tissue metastases, but no skeletal changes on MRI. CONCLUSION: WBS, SPECT and SPECT/ldCT were less sensitive than MRI and equally specific for the detection of bone metastases in patients with advanced breast cancer. Based on our findings, we suggest that initial staging include WBS, MRI of the spine and CT for soft tissue evaluation. Further studies may clarify the potential benefits of whole-body MRI and 18F-NaF PET/CT or 18F-FDG PET/CT.

The influence of a rectal ultrasound probe on the separation between prostate and rectum in high-dose-rate brachytherapy.

PURPOSE: The aim of this study was to compare the distance between prostate and rectum as well as rectal dose-volume histogram (DVH) parameters for high-dose-rate (HDR) prostate brachytherapy (BT) with and without a transrectal ultrasound (US) probe in place during delivery. METHODS AND MATERIALS: The study included 20 patients with high-risk prostate cancer treated consecutively with combined external beam radiotherapy (EBRT) and MRI-based HDR-BT. The MRI-based HDR-BT dose plan and prostate gland contour were transferred to the US images after rigid MRI/US coregistration, followed by delineation of the rectum on US images acquired with a transrectal US probe. The prostate-rectum separation was estimated at the apex, reference, and base plane on the US (with rectal probe) and MR images (without rectal probe). Rectal DVH parameters for EBRT + HDR-BT given in equivalent 2 Gy fractionation doses were estimated and compared for US-based and MRI-based HDR-BT dose planning. RESULTS: The median (and range) prostate-rectum separation increased on MR images (without rectal probe) as compared with on US images (with rectal probe) by 10 mm (-5, 18) at the base, 1 mm (-2, 3) at the reference and decreased at the apex by 2 mm (-5, 11). The rectal D5.0cm3, D2.0cm3, and D0.1cm3 decreased by a median of 4 Gy (-1, 10), 4 Gy (-2, 13), and 7 Gy (-4, 26), respectively. CONCLUSIONS: MRI-based HDR-BT without a rectal US probe in place as compared with US-based BT with the probe in place demonstrated a significant increase in the prostate-rectum separation, with a potential of reducing rectal dose.

Diffusion-weighted magnetic resonance imaging during radiotherapy of locally advanced cervical cancer--treatment response assessment using different segmentation methods.

BACKGROUND: Diffusion-weighted magnetic resonance imaging (DW-MRI) and the derived apparent diffusion coefficient (ADC) value has potential for monitoring tumor response to radiotherapy (RT). Method used for segmentation of volumes with reduced diffusion will influence both volume size and observed distribution of ADC values. This study evaluates: 1) different segmentation methods; and 2) how they affect assessment of tumor ADC value during RT. MATERIAL AND METHODS: Eleven patients with locally advanced cervical cancer underwent MRI three times during their RT: prior to start of RT (PRERT), two weeks into external beam RT (WK2RT) and one week prior to brachytherapy (PREBT). Volumes on DW-MRI were segmented using three semi-automatic segmentation methods: "cluster analysis", "relative signal intensity (SD4)" and "region growing". Segmented volumes were compared to the gross tumor volume (GTV) identified on T2-weighted MR images using the Jaccard similarity index (JSI). ADC values from segmented volumes were compared and changes of ADC values during therapy were evaluated. RESULTS: Significant difference between the four volumes (GTV, DWIcluster, DWISD4 and DWIregion) was found (p < 0.01), and the volumes changed significantly during treatment (p < 0.01). There was a significant difference in JSI among segmentation methods at time of PRERT (p < 0.016) with region growing having the lowest JSIGTV (mean± sd: 0.35 ± 0.1), followed by the SD4 method (mean± sd: 0.50 ± 0.1) and clustering (mean± sd: 0.52 ± 0.3). There was no significant difference in mean ADC value compared at same treatment time. Mean tumor ADC value increased significantly (p < 0.01) for all methods across treatment time. CONCLUSION: Among the three semi-automatic segmentations of hyper-intense intensities on DW-MR images implemented, cluster analysis and relative signal thresholding had the greatest similarity to the clinical tumor volume. Evaluation of mean ADC value did not depend on segmentation method.