Post-treatment Magnetic Resonance Imaging Research Articles

Desmoid fibromatosis: MRI features of response to systemic therapy.

Imaging criteria for measuring the response of desmoid fibromatosis to systemic therapy are not well established. We evaluated a series of patients with desmoids who underwent systemic therapy to document magnetic resonance imaging (MRI) features associated with a positive clinical response. This Institutional Review Board-approved retrospective study included 23 patients (mean age 40.5) with 29 extra-abdominal tumors. Therapeutic regimens included cytotoxic chemotherapy (n = 19), targeted therapy (n = 3), and nonsteroid anti-inflammatory drugs (NSAIDS; n = 1). Clinical effects were categorized as progressive disease, stable, or partial response. Maximum tumor dimension (Dmax), approximate tumor volume (VTumor), and quantitative tumor T2 hyperintensity and contrast enhancement (relative to muscle) for pre- and post-treatment MRIs were compared. Three lesions progressed, 5 lesions were stable, whereas 21 showed a clinical response. Dmax decreased more in responders (mean -11.0%) than in stable/progressive lesions (mean -3.6 and 0% respectively, p = 0.28, ANOVA); by Response Evaluation Criteria in Solid Tumors (RECIST 1.1) 27 out of 29 lesions were "stable," including the 3 progressive lesions. In responders, VTumor change averaged -29.4%, but -19.2% and +32.5% in stable and progressive lesions respectively (p = 0.002, ANOVA); by 3D criteria 14 out of 29 lesions showed a partial response. T2 hyperintensity decreased by 50-54% in partial response/stable disease, but only by 10% in progressive lesions (p = 0.049, t test). Changes in contrast enhancement ranged from -23% to 0%, but were not statistically significant among response groups (p = 0.37). Change in T2 hyperintensity showed a positive correlation with volumetric change (r = 0.40). Decreases in volume and T2 hyperintensity reflect the positive response of desmoid fibromatosis to systemic therapy; RECIST 1.1 criteria are not sensitive to clinically determined tumor response.

Final Results of a Phase I/II Multicenter Trial of WST11 Vascular Targeted Photodynamic Therapy for Hemi-Ablation of the Prostate in Men with Unilateral Low Risk Prostate Cancer Performed in the United States

Vascular targeted photodynamic therapy with WST11 (TOOKAD® Soluble) is a form of tissue ablation that may be used therapeutically for localized prostate cancer. To study dosing parameters and associated treatment effects we performed a prospective, multicenter, phase I/II trial of WST11 vascular targeted photodynamic therapy of prostate cancer. A total of 30 men with unilateral, low volume, Gleason 3+ 3 prostate cancer were enrolled at 5 centers after local institutional review board approval. Light energy, fiber number and WST11 dose were escalated to identify optimal dosing parameters for vascular targeted photodynamic therapy hemi-ablation. Men were treated with photodynamic therapy and evaluated by posttreatment magnetic resonance imaging and biopsy. Prostate specific antigen, light dose index (defined as fiber length/desired treatment volume), toxicity and quality of life parameters were recorded. After dose escalation 21 men received optimized dosing of 4 mg/kg WST11 at 200 J energy. On posttreatment biopsy residual prostate cancer was found in the treated lobe in 10 men, the untreated lobe in 4 and both lobes in 1. At a light dose index of 1 or greater with optimal dosing in 15 men 73.3% had a negative biopsy in the treated lobe. Six men undergoing retreatment with the optimal dose and a light dose index of 1 or greater had a negative posttreatment biopsy. Minimal effects were observed on urinary and sexual function, and overall quality of life. Hemi-ablation of the prostate with WST11 vascular targeted photodynamic therapy was well tolerated and resulted in a negative biopsy in the treated lobe in the majority of men. Dosing parameters and the light dose index appear related to tissue response as determined by magnetic resonance imaging and biopsy. These parameters may serve as the basis for further prospective studies.

Long-Term Effect of Flow Diversion on Large and Giant Aneurysms: MRI-DSA Clinical Correlation Study

The long-term effect of flow diversion (FD) on aneurysms has not been well studied. We aimed to assess the effect of the Pipeline embolization device (Covidien, Irvine, California, USA) on large and giant intracranial aneurysms with magnetic resonance imaging (MRI) and digital subtraction angiography (DSA) and then correlate with clinical follow-up. We conducted a retrospective analysis of aneurysms treated solely with Pipeline without adjunctive therapy. The largest aneurysm diameters were compared with pretreatment and post treatment MRI and correlated with DSA and clinical symptoms. Twelve patients harboring large and giant saccular unruptured aneurysms, treated with Pipeline, were included. Mean follow-up times were as follows: MRI 22.8 months (range 1-57), DSA 18.2 months (range 1-33), and clinical 29 months (range 1-48). Ten (83%) of 12 treated aneurysms decreased in size on MRI, which was first seen at an average of 17 months (range 4-57). In 70% of patients the change was noted on MRI ≤1 year after treatment, at an average of 9.1 months (range 4-12). MRI reduction was more likely in angiographically occluded aneurysms. Five aneurysms with complete occlusion on early angiogram showed size reduction on MRI only at ≥12 months. Mean aneurysm size reduction was 57% (range 19.6-94.2), which correlated well with improvement of cranial neuropathies in 75% and headaches in 100% of patients. Most aneurysms treated with Pipeline decreased in size, correlating with clinical improvement. Some aneurysms remained unchanged on MRI until a later time point despite early DSA occlusion. It may be reasonable to eliminate early postprocedural imaging and start follow-up only as late as 1 year after FD treatment in clinically stable, asymptomatic patients.

216-37: A prospective, randomized clinical evaluation of the safety and efficacy of an MR Conditional pacing system in subjects undergoing Cardiac Magnetic Resonance Imaging (MRI)

Purpose: There are limited published data from controlled studies on pacemaker implanted patients who underwent a Cardiac MRI scan. The purpose of this prospective, international, multi-center, randomized study was to demonstrate safety and efficacy of the SJM MRI conditional pacing system in patients undergoing cardiac MRI scan. Methods: Patients (n = 283) indicated for dual chamber pacemaker implant were invited to provide voluntary consent at 15 centers across Asia and randomized either to the MRI scan group (SG; n = 140) or the Control group (CG; n = 143) post successful device implantation (Accent MRITM DDDR, Tendril MRITM lead, St. Jude Medical). Each patient in SG (within 9 – 12 weeks post-implant) underwent an elective, prespecificed, non-diagnostic cardiac MRI scan in a 1.5 Tesla horizontal cylindrical bore scanning machine with total magnet exposure time of approximately 60 minutes, maximized gradient slew rate of up to 200 T/m/s and whole body SAR < 4W/kg. Clinical evaluation and device interrogation were performed at baseline, pre and post MRI scan visit and 1-month post MRI for all enrolled patients. The primary endpoint for device safety was freedom from MRI-related complications. The primary endpoint for device efficacy was change in RA/RV capture threshold and sensing amplitude from the MRI visit to 1 month post-MRI visit. Summary of results: The study achieved both safety and efficacy endpoints with 118 patients completing the 1 month post MRI scan visit reporting 100% freedom from MRI scan related complications at the 1 Month post Cardiac MRI Scan follow-up visit (95% LCB: 97.4%). The study reported 12 SADEs & 28 SAEs all of which were found to be not related to MRI scan. No significant changes in device performance with respect to RA/RV capture threshold and RA/RV sensing amplitude from the MRI visit to 1 month post-MRI visit were observed between CG and SG groups (Table 1). Change in RA/RV lead efficacy parameters# #Minimum 113 subjects were required in each group to achieve more than 90% of power at a one sided significant level of 5% to show the non-inferiority with a margin of 10% *n - Number of subjects who experienced an increase in RA capture threshold @ 0.5 ms at 1 M post-MRI scan ≤ 0.5V compared to pre-MRI testing *n - Number of subjects who experienced a decrease in RA sensing amplitude ≤ 50% and ≥ 1.5 mV at 1 M post-MRI scan compared to pre-MRI testing Change in RA/RV lead efficacy parameters# #Minimum 113 subjects were required in each group to achieve more than 90% of power at a one sided significant level of 5% to show the non-inferiority with a margin of 10% *n - Number of subjects who experienced an increase in RA capture threshold @ 0.5 ms at 1 M post-MRI scan ≤ 0.5V compared to pre-MRI testing *n - Number of subjects who experienced a decrease in RA sensing amplitude ≤ 50% and ≥ 1.5 mV at 1 M post-MRI scan compared to pre-MRI testing Conclusions: This study of the St. Jude Medical Accent MRITM pacemaker system in patients undergoing 1.5T cardiac MRI scans at up to 4W/kg successfully met the safety and efficacy endpoints.

Regeneration of Cartilage in Human Knee Osteoarthritis with Autologous Adipose Tissue-Derived Stem Cells and Autologous Extracellular Matrix.

This clinical case series demonstrates that percutaneous injections of autologous adipose tissue-derived stem cells (ADSCs) and homogenized extracellular matrix (ECM) in the form of adipose stromal vascular fraction (SVF), along with hyaluronic acid (HA) and platelet-rich plasma (PRP) activated by calcium chloride, could regenerate cartilage-like tissue in human knee osteoarthritis (OA) patients. Autologous lipoaspirates were obtained from adipose tissue of the abdominal origin. Afterward, the lipoaspirates were minced to homogenize the ECM. These homogenized lipoaspirates were then mixed with collagenase and incubated. The resulting mixture of ADSCs and ECM in the form of SVF was injected, along with HA and PRP activated by calcium chloride, into knees of three Korean patients with OA. The same affected knees were reinjected weekly with additional PRP activated by calcium chloride for 3 weeks. Pretreatment and post-treatment magnetic resonance imaging (MRI) data, functional rating index, range of motion (ROM), and pain score data were then analyzed. All patients' MRI data showed cartilage-like tissue regeneration. Along with MRI evidence, the measured physical therapy outcomes in terms of ROM, subjective pain, and functional status were all improved. This study demonstrates that percutaneous injection of ADSCs with ECM contained in autologous adipose SVF, in conjunction with HA and PRP activated by calcium chloride, is a safe and potentially effective minimally invasive therapy for OA of human knees.

Management of advanced nodal disease following chemoradiation for head and neck squamous cell carcinoma: role of magnetic resonance imaging.

The purpose of this study was to determine the role of magnetic resonance imaging (MRI) to predict persistent nodal disease in head and neck cancer treated with chemoradiation. Retrospective chart review of 38 patients with head and neck cancer and N2/N3 neck disease who were treated with chemoradiation and who had an MRI 6 to 8 weeks following treatment. Sixteen patients had MRI findings suggestive of persistent nodal disease and were managed with neck dissections, three of whom had a persistent tumour. All of these patients have remained disease free in the neck (average follow-up 15 months). Among 22 patients without evidence of nodal disease on post-treatment MRI, 2 patients have had recurrence in the neck (average follow-up 26 months). Concomitant chemoradiation is effective for the treatment of advanced nodal disease in selected patients. Patients without MRI evidence of persistent nodal disease following chemoradiation who were observed had a low incidence (9%) of eventual neck recurrence, whereas those with evidence of persistent nodes on MRI had a 19% likelihood of residual pathologic neck disease. The optimal strategy for the evaluation of the neck following chemoradiation requires further investigation.

Prospective Validation of a Low Rectal Cancer Magnetic Resonance Imaging Staging System and Development of a Local Recurrence Risk Stratification Model: The MERCURY II Study.

This study aimed to validate a magnetic resonance imaging (MRI) staging classification that preoperatively assessed the relationship between tumor and the low rectal cancer surgical resection plane (mrLRP). Low rectal cancer oncological outcomes remain a global challenge, evidenced by high pathological circumferential resection margin (pCRM) rates and unacceptable variations in permanent colostomies. Between 2008 and 2012, a prospective, observational, multicenter study (MERCURY II) recruited 279 patients with adenocarcinoma 6 cm or less from the anal verge. MRI assessed the following: mrLRP "safe or unsafe," venous invasion (mrEMVI), depth of spread, node status, tumor height, and tumor quadrant. MRI-based treatment recommendations were compared against final management and pCRM outcomes. Overall pCRM involvement was 9.0% [95% confidence interval (CI), 5.9-12.3], significantly lower than previously reported rates of 30%. Patients with no adverse MRI features and a "safe" mrLRP underwent sphincter-preserving surgery without preoperative radiotherapy, resulting in a 1.6% pCRM rate. The pCRM rate increased 5-fold for an "unsafe" compared with "safe" preoperative mrLRP [odds ratio (OR) = 5.5; 95% CI, 2.3-13.3)]. Posttreatment MRI reassessment indicated a "safe" ymrLRP in 33 of 113 (29.2%), none of whom had ypCRM involvement. In contrast, persistent "unsafe" ymrLRP posttherapy resulted in 17.5% ypCRM involvement. Further independent MRI assessed risk factors were EMVI (OR = 3.8; 95% CI, 1.5-9.6), tumors less than 4.0 cm from the anal verge (OR = 3.4; 95% CI, 1.3-8.8), and anterior tumors (OR = 2.8; 95% CI, 1.1-6.8). The study validated MRI low rectal plane assessment, reducing pCRM involvement and avoiding overtreatment through selective preoperative therapy and rationalized use of permanent colostomy. It also highlights the importance of posttreatment restaging.

Three-dimensional Radiologic Assessment of Chemotherapy Response in Ewing Sarcoma Can Be Used to Predict Clinical Outcome.

Purpose To compare the agreement of three-dimensional (3D) tumor measurements for therapeutic response assessment of Ewing sarcoma according to the Children's Oncology Group (COG) criteria, one-dimensional (1D) Response Evaluation Criteria in Solid Tumors (RECIST), and two-dimensional (2D) measurements defined by the World Health Organization (WHO) with tumor volume measurements as the standard of reference and to determine which method correlates best with clinical outcomes. Materials and Methods This retrospective study was approved by the institutional review board of three institutions. Seventy-four patients (mean age ± standard deviation, 14.5 years ± 6.5) with newly diagnosed Ewing sarcoma treated at three medical centers were evaluated. Primary tumor size was assessed on pre- and posttreatment magnetic resonance images according to 1D RECIST, 2D WHO, and 3D COG measurements. Tumor responses were compared with the standard of reference (tumor volume) on the basis of RECIST, COG, and WHO therapeutic response thresholds. Agreement between the percentage reduction measurements of the methods was assessed with concordance correlation, Bland-Altman analysis, and Spearman rank correlation. Agreement between therapeutic responses was assessed with Kendall tau and unweighted κ statistics. Tumor responses were compared with patient survival by using the log-rank test, Kaplan-Meier plots, and Cox regression. Results Agreement with the reference standard was significantly better for 3D measurement than for 1D and 2D measurements on the basis of RECIST and COG therapeutic response thresholds (concordance correlation of 0.41, 0.72, and 0.84 for 1D, 2D, and 3D measurements, respectively; P < .0001). Comparison of overall survival of responders and nonresponders demonstrated P values of .4133, .0112, .0032, and .0027 for 1D, 2D, 3D, and volume measurements, respectively, indicating that higher dimensional measurements were significantly better predictors of overall survival. Conclusion The 3D tumor measurements according to COG are better predictors of therapeutic response of Ewing sarcoma than 1D RECIST or 2D WHO measurements and show a significantly higher correlation with clinical outcomes. (©) RSNA, 2016 Online supplemental material is available for this article.

Diagnostic accuracy of MRI to evaluate tumour response and residual tumour size after neoadjuvant chemotherapy in breast cancer patients.

BackgroundThe aim, of the study was to estimate the accuracy of magnetic resonance imaging (MRI) in assessing residual disease in breast cancer patients receiving neoadjuvant chemotherapy (NAC) and to identify the clinico-pathological factors that affect the diagnostic accuracy of breast MRI to determine residual tumour size following NAC.Patients and methods91 breast cancer patients undergoing NAC (92 breast lesions) were included in the study. Breast MRI was performed at baseline and after completion of NAC. Treatment response was evaluated by MRI and histopathological examination to investigate the ability of MRI to predict tumour response. Residual tumour size was measured on post-treatment MRI and compared with pathology in 89 lesions. Clinicopathological factors were analyzed to compare MRI-pathologic size differences.ResultsThe overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for diagnosing invasive residual disease by using MRI were 75.00%, 78.57%, 88.89%, 57.89%, and 76.09% respectively. The Pearson’s correlation coefficient (r) between tumour sizes determined by MRI and pathology was r = 0.648 (p < 0.001). The size discrepancy was significantly lower in cancers with initial MRI size ≤ 5 cm (p = 0.050), in cancers with high tumour grade (p < 0.001), and in patients with hormonal receptor-negative cancer (p = 0.033).ConclusionsMRI is an accurate tool for evaluating tumour response after NAC. The accuracy of MRI in estimating residual tumour size varies with the baseline MRI tumour size, the tumour grade and the hormonal receptor status.

Abstract WP52: Impact of Baseline DWI ASPECTS Lesion Topology on Functional Outcome after Endovascular Treatment

Introduction: Acute brain infarction (BI) topology determined by diffusion weighted imaging - Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS) on post-treatment magnetic resonance imaging (MRI) has been associated with clinical outcome in internal carotid artery (ICA) or proximal middle cerebral artery (MCA) occlusion treated by endovascular reperfusion therapy (EVRT). Hypothesis: We hypothesize that among the same type of patients, the topology of acute BI captured by DWI ASPECTS on baseline MRI may be associated with 3 months functional outcome after EVRT. Methods: Consecutive patients with an acute BI complicating ICA or proximal MCA occlusion treated by EVRT after a baseline MRI before treatment at a single center between April 2007 and March 2013 were enrolled. Poor functional outcome was defined by modified Rankin Scale (mRS) of 3 to 6 at 3 months. We used penalized logistic regression due to the multicollinearity between DWI-ASPECTS sites to assess the relationship between each DWI-ASPECTS sites and functional outcome after adjustment for age, sex, blood pressure, DWI lesion volume and infarct side. We estimated this relationship in the full cohort of patients and according to the achievement of a complete recanalization. Results: We enrolled 206 patients [mean age 71 ± 16.5, median NIHSS 16 (IQR 10-21)]. Among them 58 (28%) had an ICA occlusion, 115 (56%) a MCA M1 occlusion and 33 (16%) a MCA M2 occlusion. Median DWI lesion volume was 13 mL (IQR 4-43), and median DWI ASPECTS score was 6 (IQR 4-8). A complete recanalization was achieved among 96 patients (47%), after a median time from onset of 237 min (IQR:185-282). The involvement of the lentiform nucleus was associated with poor functional outcome in the full cohort of patients [OR : 10; 95% CI (5-23); p&lt;0.0001]. This relationship was observed in the subgroup of patients who did experience a complete recanalization [OR : 4; 95% CI (1.5-12); p=0.007] and among those who did not [OR : 21; 95% CI (5-92); p&lt;0.0001]. Conclusions: In conclusion, the involvement of the DWI ASPECTS lentiform region on baseline MRI in patients experiencing an acute BI complicating an ICA or MCA occlusion treated by EVRT was associated with poor functional outcome, overall and despite a complete recanalization.

A prospective study of the value of pre- and post-treatment magnetic resonance imaging examinations for advanced cervical cancer.

Background and aimCervical cancer has high incidence and mortality in developing countries. It is the only gynecological malignancy that is clinically staged. Staging at the time of diagnosis is crucial for treatment planning. After radiation therapy, clinical examination is limited because of radiation changes. An imaging method relatively unaffected by radiation changes would be useful for the assessment of therapy results and for management.We sought to demonstrate the value of magnetic resonance imaging (MRI) in the pre- and post-treatment assessment of cervical cancer.MethodsThis was a prospective study, carried out between November 2012 and October 2014 on 18 subjects with advanced-stage cervical cancer diagnosed by colposcopy. The disease stage was determined clinically according to the International Federation of Gynecology and Obstetrics (FIGO) criteria. Only patients with disease stage ≥ IIB or IIA with one of the tumor dimensions > 4 cm were enrolled in the study. All patients underwent abdominal-pelvic contrast-enhanced MRI as part of the workup. Tumor size, local invasion, involved pelvic lymph nodes, and staging according to MRI criteria were evaluated. Clinical and MRI examinations were also performed after chemoradiotherapy. After chemoradiotherapy, 94% of the patients (17 of 18) were treated surgically.ResultsEighteen patients aged 32–67 met the inclusion criteria and were enrolled: 10 stage IIB, 6 stage IIIA, 1 stage IIA and 1 stage IIIB, according to clinical staging. Using histopathological findings as a reference, MRI staging accuracy was 83.3%. The concordance of the clinical stage with MRI stage at the first examination was 56%. Parametrial involvement was assessed on pretreatment and post-treatment MRI, with post-treatment MRI compared with histology. There was no statistically significant difference between the pre- and post-therapy gynecological examinations (GYN) and the corresponding MRI assessments as to tumor size measurements (p>0.05). The post-therapy restoration of the cervical stroma ruled out tumor recurrence.ConclusionsFor a detailed characterization of loco-regional extension, the calculation of tumor volume, and the evaluation of distant metastatic changes, clinical examination is insufficient. Magnetic resonance imaging is helpful aftertherapy.

Focal Laser Ablation of Prostate Cancer: Phase I Clinical Trial

Focal laser ablation is an investigational technique to treat prostate cancer in a region confined manner via coagulative necrosis. This phase I trial primarily examines the safety of transrectal magnetic resonance imaging guided (in-bore) focal laser ablation in men with intermediate risk prostate cancer. An exploratory end point is cancer control after 6 months. In an institutional review board approved trial we studied focal laser ablation in 8 men with intermediate risk prostate cancer diagnosed using magnetic resonance-ultrasound fusion. Focal laser ablation was performed by inserting a cylindrically diffusing, water cooled laser fiber into magnetic resonance visible regions of interest, followed by interstitial heating at 10 to 15 W for up to 3 minutes. Secondary safety monitors (thermal probes) were inserted to assess the accuracy of magnetic resonance thermometry. Comprehensive magnetic resonance-ultrasound fusion biopsy was performed after 6months. Adverse events and health related quality of life questionnaires were recorded. Focal laser ablation was successfully performed in all 8 subjects. No grade 3 or greater adverse events occurred and no changes in International Prostate Symptom Score or International Index of Erectile Function 5 were observed. Ablation zones, as measured by posttreatment magnetic resonance imaging, had a median volume of 3 cc or 7.7% of prostate volume. Prostate specific antigen decreased in 7 men (p <0.01). At followup magnetic resonance-ultrasound fusion biopsy cancer was not detected in the ablation zone in 5 men but was present outside the treatment margin in 6 men. Focal laser ablation of the prostate is feasible and safe in men with intermediate risk prostate cancer without serious adverse events or changes in urinary or sexual function at 6 months. Comprehensive biopsy followup indicates that larger treatment margins than previously thought necessary may be required for complete tumor ablation.

Angioarchitecture and Posttreatment Magnetic Resonance Imaging Characteristics of Brain Arteriovenous Malformations and Long-Term Seizure Control After Radiosurgery

To corroborate which pretreatment angioarchitectural characteristics and posttreatment magnetic resonance imaging (MRI) features were associated with better seizure and antiepileptic drug outcomes in patients with brain arteriovenous malformations (AVMs) treated by Gamma Knife radiosurgery. During the period 2007-2010, 220 patients with intracranial AVMs undergoing radiosurgery at our hospital were evaluated. Imaging features on digital subtraction angiography and follow-up MRI, medical records, and direct patient interview were retrospectively assessed. Seizure outcome was assessed using the Engel classification and the status of antiepileptic drug use. At the last follow-up, 21 of 31 patients (68%) who met the recruitment criteria had AVM obliteration on digital subtraction angiography or MRI. Seizure-free status (Engel class 1) was achieved in 20 patients (65%), and 13 of 20 (65%) seizure-free patients were medication-free. The presence of total obliteration at last imaging follow-up (P = 0.013), absent retrograde cortical veins on digital subtraction angiography before GKRS (P = 0.013), nidus <3.7 cm (P = 0.006), and lower modified radiosurgery-based AVM score (P = 0.026) were significant predictors of seizure-free outcome. The strongest independent predictor of seizure-free status was absence of retrograde veins (odds ratio = 9.9). No angioarchitectural feature, postradiosurgery imaging finding on MRI, or radiosurgical treatment parameter was a significant predictor of seizure control or cessation of medication in seizure-free patients. This study suggests that radiosurgery provides favorable outcomes in patients with AVM-related epilepsy. Patients with intracranial AVMs can benefit from seizure control after GKRS before undergoing AVM obliteration. Absence of retrograde veins is associated with better seizure-free outcomes, regardless of the parenchymal changes after radiosurgery.

Breast Cancer in the Elderly: Is MRI Helpful?

Appropriate use of magnetic resonance imaging (MRI) in elderly breast cancer (BC) patients remains unclear; we sought to identify the indications and implications of MRI use in our elderly BC population. Women 70 years of age or older at first BC diagnosis with an MRI performed at our institution either perioperatively or in follow-up were included from a prospectively maintained database from 2000 to 2010. Univariate logistic regression was used to test associations with disease identified by MRI only (additional ipsilateral, contralateral, or new cancer) following perioperative MRI. 305 BCs were imaged in 286 patients. 133 were imaged with MRI in the perioperative setting alone, 88 had only follow-up MRIs after BC treatment, and 65 had both. Indications for perioperative MRI include: extent of disease evaluation (181; 91%); occult primary (10; 5%); high-risk screening (5; 3%); and abnormal physical exam with negative conventional imaging (2; 1%). Disease identified by MRI only for occult primary cases was 4/10 (40%; 95% confidence interval: 12.2-73.8%) and 14/181 (7.7%; 95% confidence interval: 4.3-12.6%) for perioperative MRIs performed for extent of disease evaluation. Analysis of imaging and tumor characteristics failed to find significant predictors of disease identified by MRI only. A total of 369 post-treatment follow-up MRIs were performed in 148 patients with a median of 2 MRIs per patient (range 1-8), with seven cases of disease identified by MRI only (1.9%; 95% confidence interval: 0.8-3.9%). MRI had the greatest benefit in women presenting with an occult primary cancer and minimal additional benefit in elderly patients with BC undergoing MRI imaging for extent of disease evaluation or in post-treatment surveillance.

Early magnetic resonance imaging biomarkers to predict local control after high dose stereotactic body radiotherapy for patients with sarcoma spine metastases

Background ContextRecent advances in image guidance and stereotactic body radiotherapy (SBRT) have resulted in unprecedented local control for spinal metastases of all histologies. However, little is known about early imaging biomarkers of local control. PurposeThis study aimed to identify early magnetic resonance imaging (MRI) biomarkers to predict local control after SBRT for patients with sarcoma spine metastases. Study Design/SettingThis study used a retrospective case series at a large tertiary cancer center. Patient SampleFrom 2011 to 2014, 9 consecutive patients with 12 metastatic sarcoma lesions to the spine were treated with SBRT and underwent evaluation with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) both pre- and post-SBRT. Outcome MeasureChanges in perfusion metrics, including the wash-in rate constant (Ktrans), plasma volume (Vp), composite multiparametric magnetic resonance imaging (mpMRI) score, bi-dimensional tumor size, and a graded response assessment were performed and correlated to local control. MethodsAll measurements were independent and blinded by two neuroradiologists. R2 statistics were performed to document correlation, and two-tailed t tests were used to compare groups. p<.05 was deemed statistically significant. ResultsThe median time from SBRT until posttreatment MRI was 57 days. Local failure developed in one lesion (8.3%) 10 months after SBRT. The Vp mean, Ktrans mean, Vp max, and Ktrans max were significantly decreased post-SBRT as compared with pre-SBRT (58.7%, 63.2%, 59.0%, and 55.2%; all p-values <.05). Bi-dimensional tumor measurements demonstrated an average increase in size across the cohort, and 50%, 25%, and 25% of the treated lesions demonstrated features of “worsening,” “no change,” or “improvement,” respectively, by both radiologists' graded impressions. There was good inter-reader reliability for both size and subjective disease response scores (R2=0.84). The mpMRI score had 100% accuracy in predicting local control at time of last follow-up. There was no apparent correlation with size changes compared with the mpMRI score change post-SBRT (R2=0.026). ConclusionsWe report the first analysis on the utility of DCE-MRI for metastatic sarcoma spine metastases treated with SBRT. We demonstrate that early assessment at 2 months post-SBRT using size and subjective neuroradiology impressions is insufficient to judge ultimate disease progression, and that a combination of perfusion parameters provides excellent correlation to local control.

PWE-303 The accuracy of magnetic resonance imaging in the management of rectal cancer – are we meeting the standard?

Introduction Magnetic Resonance Imaging (MRI) of the pelvis informs treatment strategy in rectal cancer. Complex multidisciplinary treatment plans are formulated on the basis of TNM status and proximity of the tumour to the circumferential resection margin (CRM). Previous studies 1 report a high degree of MRI accuracy. We sought to assess the regional performance of MRI assessment of CRM. Method A total of 150 consecutive patients with rectal cancer who underwent staging MRI were identified from a prospectively collected audit database comprising 6 units within Greater Glasgow and Clyde (West of Scotland Colorectal Cancer Managed Clinical Network) between April 2012 and March 2013. Pre-operative MRI prediction of circumferential resection margin (CRM) involvement was studied in both groups receiving neoadjuvant therapy and those proceeding directly to surgical resection. In all cases the MRI prediction of CRM was compared with final pathological assessment of CRM status. Patients who had metastatic disease at initial diagnosis, did not undergo MRI or did not proceed to surgical resection were excluded. Results Of 102 patients who underwent resection of rectal cancer (either APR or anterior resection) 74 patients proceeded directly to surgery and 28 underwent neoadjuvant chemoradiotherapy prior to resection. Four patients were found to have an involved CRM at final pathological analysis (4%) (2 in the group proceeding direct to resection and 2 in the neodjuvant therapy group). The specificity of MRI prediction of CRM involvement, in the direct-to-surgery cohort was 100% (95% CI 95–100), and negative predictive value (NPV) was 97% (95% CI 90–99). However in the group receiving neoadjuvant therapy prior to resection, the post-treatment MRI had a specificity of 53% (95% CI 33–73) and NPV of 100% (95% CI 76–100). Conclusion Pelvic MRI has become commonplace in the staging of rectal cancer. The prediction of CRM involvement is critical to complex decision making 2 about treatment modalities and in particular whether neoadjuvant therapy is instituted. Local institution of MRI assessment has resulted in a favourably low rate of CRM involvement at final pathology (4%). A high NPV allows selective use of neoadjuvant therapy for those at risk of an involved CRM. Disclosure of interest None Declared. References Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study. MERCURY Study Group. BMJ. 2006 Oct 14;333(7572):779 Multicenter Evaluation of Rectal cancer ReImaging pOst Neoadjuvant (MERRION) Therapy. Hanly AM, Ryan EM, Rogers AC, McNamara DA, Madoff RD, Winter DC; MERRION Study Group. Ann Surg . 2014. Apr;259(4):723–7. doi: 10.1097/SLA.0b013e31828f6c91. PMID:23744576

Treatment of Cerebral Radiation Necrosis With Bevacizumab

Cerebral radiation necrosis (RN) is a devastating complication of radiation therapy for brain tumors. Recent studies have explored the role of bevacizumab, a humanized monoclonal antibody directed against vascular endothelial growth factor in the treatment of RN of the brain. We report 24 patients with cerebral RN who were treated with bevacizumab. Twenty-four patients diagnosed with cerebral RN and treated with different schedules of bevacizumab between July 2007 and June 2012, were identified from the Cleveland Clinic Brain Tumor and Neuro-Oncology Center's database. Pretreatment and posttreatment magnetic resonance imaging (MRI) studies were compared to evaluate bevacizumab efficacy. Posttreatment MRI demonstrated a radiographic improvement in 23 of 24 patients on the postcontrast T1-weighted MRI and fluid-attenuated inversion-recovery sequences. Using the McDonald criteria, the average change in the T1-weighted postcontrast MRI was a decrease of 48.1%, and the average change in the fluid-attenuated inversion-recovery images was a decrease of 53.7%. There was a mean daily dose reduction of 9.4 mg of dexamethasone after initiation of bevacizumab in patients who were on steroids at the start of bevaciuzmab therapy for RN. Treatment with bevacizumab was well tolerated with only 1 grade 3 adverse event. The current study demonstrates that bevacizumab treatment results in excellent clinical and radiologic response in patients with RN caused by common forms of radiation therapy. The safety profile of bevacizumab use in RN is acceptable. In the current study, we found no difference between different schedules of bevacizumab in treatment outcomes.

Sildenafil for microcystic lymphatic malformations of the head and neck: A prospective study

BackgroundMicrocystic lymphatic malformations (LM) are congenital birth defects that can cause severe functional or esthetic deformity. At this time, several treatment interventions are possible, but there is no ideal therapy. A recently published article noted a coincidental improvement in microcystic LMs with the use of sildenafil for pulmonary hypertension, but conclusive and reproducible data is lacking regarding its efficacy. Methods and resultsA prospective study was conducted to examine the subjective and objective results associated with sildenafil use in the treatment of microcystic LMs. Patients under the age of 18 were enrolled, and after evaluation with pre-intervention magnetic resonance imaging (MRI) studies, each was given a 6-week course of sildenafil. Subjective outcomes were obtained, and postoperative MRIs were used to objectively quantify changes.Five patients between the ages of 4 and 11 were enrolled in the study. All patients had microcystic LMs of the head and neck. All patients had undergone previous treatment interventions utilizing various modalities, and each was now seeking treatment for functional and cosmetic purposes. All patients had minimal to no response from a subjective standpoint. Comparison of pre- and post-treatment MRIs also demonstrated minimal to no response. ConclusionsThe use of sildenafil for the treatment of microcystic lymphatic malformations did not have any appreciable effect on our selected population of pediatric patients who had been resistant to previous therapies. Further studies would be necessary to determine if other cohorts may benefit.

Hyperbaric oxygen for stage I and II femoral head osteonecrosis.

Hyperbaric oxygen therapy is a suggested joint-preserving treatment for symptomatic early-stage osteonecrosis of the femoral head. Limited studies of this treatment have been published. The goal of this study was to evaluate the effectiveness of this treatment in a relatively large patient cohort. The authors reviewed the files of 68 patients with 78 symptomatic joints with Steinberg stage I and II osteonecrosis of the femoral head. All patients were treated with hyperbaric oxygen at the authors' medical health center. Pretreatment and immediate posttreatment magnetic resonance imaging (MRI) findings were compared. On follow-up, a telephone interview was conducted to determine the survival of the joint. Modified Harris Hip Score and Short Form 12 health survey (SF-12) questionnaires of the start of treatment and at follow-up were obtained and evaluated for statistically significant differences. Half of the joints were stage 1 and half were stage II. Seventy-four joints underwent both pre- and posttreatment MRI. Eighty-eight percent of joints showed improvement posttreatment. On follow-up at a mean of 11.1±5.1 years, 54 patients (58 joints) were located and answered the questionnaires. At the time of follow-up, 93% of the joints survived. Mean Harris Hip Score improved from 21 to 81 (P<.0001), the mean physical component of the SF-12 improved from 24 to 46 (P<.0001), and the mean mental component of the SF-12 improved from 54 to 59 (P<.0001). The authors concluded that hyperbaric oxygen treatment is effective in preserving the hip joint in stage I and II osteonecrosis of the femoral head.

Patients' oral hydration levels and incidence of immediate to short-term mild side-effects in contrast agent enhanced MRI diagnostics

AimGadolinium-based contrast agents for radiodiagnostic purposes can lead to side effects, including nephrotoxicity in patients with renal insufficiency. This study evaluated whether the occurrence of mild side effects from gadolinium-based contrast enhanced magnetic resonance imaging (MRI) correlates to patients' oral hydration levels. MethodsOral fluid intake levels 24 h pre- and 24 h post-MRI, as well as incidence of mild side-effects experienced 30 min and 24 h post-MRI were recorded by using a patient self-reporting questionnaire. ResultsA total of 174 patients, 29 controls, 98 administered Prohance and 47 receiving Dotarem, were enrolled. Overall, the most frequently reported side-effect was headache; nausea only occurred in patients receiving contrast agent. One or more side-effects experienced 24 h following the MRI scan were reported by 10% (controls), 24% (Prohance) and 22% (Dotarem) of patients, respectively. Multivariate ordinal regression analysis showed that only male gender (OR 0.24, 95% CI 0.11–0.53) was statistically significantly associated with a decreased incidence of side-effects 30 min after MRI. At 24-h post MRI, a lack of contrast agent (OR 0.40, 95% CI 0.09–1.74) and male gender (OR 0.46, 95% CI 0.19–1.09) were associated with fewer side-effects. ConclusionsThe level oral fluid intake before and after undergoing gadolinium-based contrast-enhanced MRI does not appear to markedly affect the incidence of common undesirable mild symptoms experienced shortly after the procedure. Confounding differences between patients in reporting side-effects may contribute to these findings.