Merel Huisman

Effectiveness of Reirradiation for Painful Bone Metastases: A Systematic Review and Meta-Analysis

PURPOSE Reirradiation of painful bone metastases in nonresponders or patients with recurrent pain after initial response is performed in up to 42% of patients initially treated with radiotherapy. Literature on the effect of reirradiation for pain control in those patients is scarce. In this systematic review and meta-analysis, we quantify the effectiveness of reirradiation for achieving pain control in patients with painful bone metastases. METHODS AND MATERIALS A free text search was performed to identify eligible studies using the MEDLINE, EMBASE, and the Cochrane Collaboration library electronic databases. After study selection and quality assessment, a pooled estimate was calculated for overall pain response for reirradiation of metastatic bone pain. RESULTS Our literature search identified 707 titles, of which 10 articles were selected for systematic review and seven entered the meta-analysis. Overall study quality was mediocre. Of the 2,694 patients initially treated for metastatic bone pain, 527 (20%) patients underwent reirradiation. Overall, a pain response after reirradiation was achieved in 58% of patients (pooled overall response rate 0.58, 95% confidence interval = 0.49-0.67). There was a substantial between-study heterogeneity (I² = 63.3%, p = 0.01) because of clinical and methodological differences between studies. CONCLUSIONS Reirradiation of painful bone metastases is effective in terms of pain relief for a small majority of patients; approximately 40% of patients do not benefit from reirradiation. Although the validity of results is limited, this meta-analysis provides a comprehensive overview and the most quantitative estimate of reirradiation effectiveness to date.

Spinal instability as defined by the spinal instability neoplastic score is associated with radiotherapy failure in metastatic spinal disease

BACKGROUND CONTEXT Although radiotherapy is effective in achieving pain relief in most patients, it is not completely understood why some patients respond well to radiotherapy and others do not. Our hypothesis was that metastatic bone pain, if predominantly caused by mechanical instability of the spine, responds less well to radiotherapy than metastatic bone pain caused by local tumor activity. Recently, the spinal instability neoplastic score (SINS) was proposed as a standardized referral tool for nonspine specialists to facilitate early diagnosis of spinal instability. PURPOSE To investigate the association between spinal instability as defined by the SINS and response to radiotherapy in patients with spinal metastases. STUDY DESIGN A retrospectively matched case-control study in an academic tertiary referral center, conducted according to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines. PATIENT SAMPLE Thirty-eight patients with spinal metastases who were retreated after initial palliative radiotherapy from January 2009 to December 2010 were matched to 76 control patients who were not retreated. OUTCOME MEASURES Radiotherapy failure as defined by retreatment (radiotherapy, surgery, and conservative) after palliative radiotherapy for spinal metastases. METHODS Radiotherapy planning computed tomography scans were scored by a blinded spine surgeon according to the SINS criteria. The association between SINS and radiotherapy failure was estimated by univariate and multivariate conditional logistic regression analysis. RESULTS Median SINS was 10 (range 4-16) for cases and 7 (range 1-16) for controls. The SINS was significantly and independently associated with radiotherapy failure (adjusted odds ratio, 1.3; 95% confidence interval, 1.1-1.5; p=.01). CONCLUSIONS This study shows that a higher spinal instability score increases the risk of radiotherapy failure in patients with spinal metastases, independent of performance status, primary tumor, and symptoms. These results may support the hypothesis that metastatic spinal bone pain, predominantly caused by mechanical instability, responds less well to radiotherapy than pain mainly resulting from local tumor activity.

International consensus on use of focused ultrasound for painful bone metastases: Current status and future directions

Abstract Focused ultrasound surgery (FUS), in particular magnetic resonance guided FUS (MRgFUS), is an emerging non-invasive thermal treatment modality in oncology that has recently proven to be effective for the palliation of metastatic bone pain. A consensus panel of internationally recognised experts in focused ultrasound critically reviewed all available data and developed consensus statements to increase awareness, accelerate the development, acceptance and adoption of FUS as a treatment for painful bone metastases and provide guidance towards broader application in oncology. In this review, evidence-based consensus statements are provided for (1) current treatment goals, (2) current indications, (3) technical considerations, (4) future directions including research priorities, and (5) economic and logistical considerations.

Quality of MR thermometry during palliative MR-guided high-intensity focused ultrasound (MR-HIFU) treatment of bone metastases

BackgroundMagnetic resonance (MR)-guided high-intensity focused ultrasound has emerged as a clinical option for palliative treatment of painful bone metastases, with MR thermometry (MRT) used for treatment monitoring. In this study, the general image quality of the MRT was assessed in terms of signal-to-noise ratio (SNR) and apparent temperature variation. Also, MRT artifacts were scored for their occurrence and hampering of the treatment monitoring.MethodsAnalyses were performed on 224 MRT datasets retrieved from 13 treatments. The SNR was measured per voxel over time in magnitude images, in the target lesion and surrounding muscle, and was averaged per treatment. The standard deviation over time of the measured temperature per voxel in MRT images, in the muscle outside the heated region, was defined as the apparent temperature variation and was averaged per treatment. The scored MRT artifacts originated from the following sources: respiratory and non-respiratory time-varying field inhomogeneities, arterial ghosting, and patient motion by muscle contraction and by gross body movement. Distinction was made between lesion type, location, and procedural sedation and analgesic (PSA).ResultsThe average SNR was highest in and around osteolytic lesions (21 in lesions, 27 in surrounding muscle, n = 4) and lowest in the upper body (9 in lesions, 16 in surrounding muscle, n = 4). The average apparent temperature variation was lowest in osteolytic lesions (1.2°C, n = 4) and the highest in the upper body (1.7°C, n = 4). Respiratory time-varying field inhomogeneity MRT artifacts occurred in 85% of the datasets and hampered treatment monitoring in 81%. Non-respiratory time-varying field inhomogeneities and arterial ghosting MRT artifacts were most frequent (94% and 95%) but occurred only locally. Patient motion artifacts were highly variable and occurred less in treatments of osteolytic lesions and using propofol and esketamine as PSA.ConclusionsIn this study, the general image quality of MRT was observed to be higher in osteolytic lesions and lower in the upper body. Respiratory time-varying field inhomogeneity was the most prominent MRT artifact. Patient motion occurrence varied between treatments and seemed to be related to lesion type and type of PSA. Clinicians should be aware of these observed characteristics when interpreting MRT images.

Effectiveness of Repeat Radiotherapy for Painful Bone Metastases in Clinical Practice: A 10 Year Historical Cohort Study

AIMS Repeat radiotherapy for palliation of painful bone metastases is often prescribed to non-responders or those with recurrent pain, although studies on retreatment remain scarce. We assessed the effectiveness of retreatment for painful bone metastases in terms of pain relief in everyday clinical practice and identified factors associated with response. MATERIALS AND METHODS We carried out a single-institution 10 year retrospective cohort study among 247 patients retreated for painful bone metastases. Response was defined as a decrease in pain between 2 and 12 weeks after retreatment. The overall pain response rate was calculated in an evaluable-patients-only analysis and a worst-case analysis. Multivariate logistic regression analyses were used to identify factors associated with pain response. RESULTS A follow-up of ≥2 weeks was available in 162 of 247 patients (65%). The overall pain response was 66% (95% confidence interval 58-73%) in an evaluable-patients-only analysis and 43% (95% confidence interval 37-50%) in a worst-case analysis. Response to first irradiation (odds ratio 2.16, P = 0.049) and use of systemic therapy (odds ratio 0.39, P = 0.037) were independently associated with the response to retreatment. The median overall survival was 7.1 months. CONCLUSION In everyday clinical practice, retreatment for painful bone metastases leads to pain reduction in 66% of evaluable patients and 43% of patients in a worst-case analysis. Patients who responded to initial radiotherapy were more likely to respond again and those on systemic therapy were less likely to respond. Overall, repeat radiotherapy should be considered in patients with persisting bone pain.

Endovascular treatment of a patient with an aneurysm of the proper hepatic artery and a duodenal fistula

Aneurysms of the proper hepatic artery comprise a rare but potentially dangerous entity for which treatment is performed both surgically and endovascularly. Covered stents are generally used for endovascular treatment of such aneurysms. When the aneurysm is contaminated due to an enteric fistula, however, use of a covered stent is considered inappropriate. This case report describes the endovascular repair of a proper hepatic artery aneurysm using overlapping bare metal stents after the patient was surgically treated for duodenal hemorrhage.

3D MR neurography targeted peripheral nerve ablation with MR-guided high intensity focused ultrasound (MR-HIFU): initial results of a feasibility study in a swine model

MR-guided HIFU is an effective treatment for metastatic bone pain through periosteal nerve ablation,[1] and is being investigated for treating back pain through facet joint denervation.[2] For peripheral neuropathy, ultrasound-guided HIFU has been investigated preclinically as a means of achieving either an irreversible conduction block to treat severe spasticity,[3] or a reversible partial conduction block to alleviate chronic pain.[4] However, ultrasound offers limited visualization of deeply situated pelvic nerves [5] and lacks the ability to measure thermal dose, which predicts the extent of changes in peripheral nerve histology and function.[6] Recently developed diffusion-prepared 3D MR neurography imaging techniques with fat suppression and nerve-selective T2-weighting [7] could improve targeting accuracy over ultrasound guidance. We present initial investigations into the use of MRI to guide HIFU ablation of peripheral nerves in a swine model. The objectives were 1) to evaluate the feasibility of identifying peripheral nerves using MR neurography on the clinical MR-HIFU system, 2) to monitor HIFU ablation of peripheral nerves using MR thermometry, and 3) to evaluate the ability to measure thermal lesions in peripheral nerves using contrast-enhanced T1-weighted images and thermal dose maps calculated from MR thermometry.