Oncological and Peri-Operative Outcomes of Percutaneous Cryoablation of Renal Cell Carcinoma for Patients with Hereditary RCC Diseases-An Analysis of European Multi-Centre Prospective EuRECA Registry

This study aims to evaluate the safety, efficacy, and renal function preservation of percutaneous cryoablation (PCA) for small renal masses (SRMs) in inherited RCC syndromes. Patients with inherited T1N0M0 RCCs (<7 cm) undergoing PCA from 2015 to 2021 were identified from the European Registry for Renal Cryoablation (EuRECA). The primary outcome was local recurrence-free survival (LRFS). The secondary outcomes included technical success, peri-operative outcomes, and other oncological outcomes estimated using the Kaplan-Meier method. Simple proportions, chi-squared tests, and t-tests were used to analyse the peri-operative outcomes. A total of 68 sessions of PCA were performed in 53 patients with RCC and 85 tumours were followed-up for a mean duration of 30.4 months (SD ± 22.0). The overall technical success rate was 99%. The major post-operative complication rate was 1.7%. In total, 7.4% (2/27) of patients had >25% reduction in renal function. All oncological events were observed in VHL patients. Estimated 5-year LRFS, metastasis-free survival, cancer-specific survival, and overall survival were 96.0% (95% CI 75-99%), 96.4% (95% CI 77-99%), 90.9% (95% CI 51-99%), and 90.9% (95% CI 51-99%), respectively. PCA of RCCs for patients with hereditary RCC SRMs appears to be safe, offers low complication rates, preserves renal function, and achieves good oncological outcomes.

Comprehensive Imaging Characterization of Colorectal Liver Metastases

Colorectal liver metastases (CRLM) have heterogenous histopathological and immunohistochemical phenotypes, which are associated with variable responses to treatment and outcomes. However, this information is usually only available after resection, and therefore of limited value in treatment planning. Improved techniques for in vivo disease assessment, which can characterise the variable tumour biology, would support further personalization of management strategies. Advanced imaging of CRLM including multiparametric MRI and functional imaging techniques have the potential to provide clinically-actionable phenotypic characterisation. This includes assessment of the tumour-liver interface, internal tumour components and treatment response. Advanced analysis techniques, including radiomics and machine learning now have a growing role in assessment of imaging, providing high-dimensional imaging feature extraction which can be linked to clinical relevant tumour phenotypes, such as a the Consensus Molecular Subtypes (CMS). In this review, we outline how imaging techniques could reproducibly characterize the histopathological features of CRLM, with several matched imaging and histology examples to illustrate these features, and discuss the oncological relevance of these features. Finally, we discuss the future challenges and opportunities of CRLM imaging, with a focus on the potential value of advanced analytics including radiomics and artificial intelligence, to help inform future research in this rapidly moving field.

Consensus Guidelines for the Definition of Time-to-Event End Points in Image-guided Tumor Ablation: Results of the SIO and DATECAN Initiative

There is currently no consensus regarding preferred clinical outcome measures following image-guided tumor ablation or clear definitions of oncologic end points. This consensus document proposes standardized definitions for a broad range of oncologic outcome measures with recommendations on how to uniformly document, analyze, and report outcomes. The initiative was coordinated by the Society of Interventional Oncology in collaboration with the Definition for the Assessment of Time-to-Event End Points in Cancer Trials, or DATECAN, group. According to predefined criteria, based on experience with clinical trials, an international panel of 62 experts convened. Recommendations were developed using the validated three-step modified Delphi consensus method. Consensus was reached on when to assess outcomes per patient, per session, or per tumor; on starting and ending time and survival time definitions; and on time-to-event end points. Although no consensus was reached on the preferred classification system to report complications, quality of life, and health economics issues, the panel did agree on using the most recent version of a validated patient-reported outcome questionnaire. This article provides a framework of key opinion leader recommendations with the intent to facilitate a clear interpretation of results and standardize worldwide communication. Widespread adoption will improve reproducibility, allow for accurate comparisons, and avoid misinterpretations in the field of interventional oncology research. Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Liddell in this issue.

Synbiotics Alter Fecal Microbiomes, But Not Liver Fat or Fibrosis, in a Randomized Trial of Patients With Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Dysbiosis of the intestinal microbiota has been associated with nonalcoholic fatty liver disease (NAFLD). We investigated whether administration of a synbiotic combination of probiotic and prebiotic agents affected liver fat content, biomarkers of liver fibrosis, and the composition of the fecal microbiome in patients with NAFLD.

METHODS

We performed a double-blind phase 2 trial of 104 patients with NAFLD in the United Kingdom. Participants (mean age, 50.8 ± 12.6 years; 65% men; 37% with diabetes) were randomly assigned to groups given the synbiotic agents (fructo-oligosaccharides, 4 g twice per day, plus Bifidobacterium animalis subspecies lactis BB-12; n = 55) or placebo (n = 49) for 10-14 months. Liver fat content was measured at the start and end of the study by magnetic resonance spectroscopy, and liver fibrosis was determined from a validated biomarker scoring system and vibration-controlled transient elastography. Fecal samples were collected at the start and end of the study, the fecal microbiome were analyzed by 16S ribosomal DNA sequencing.

RESULTS

Mean baseline and end-of-study magnetic resonance spectroscopy liver fat percentage values were 32.3% ± 24.8% and 28.5% ± 20.1% in the synbiotic group and 31.3% ± 22% and 25.2% ± 17.2% in the placebo group. In the unadjusted intention-to-treat analysis, we found no significant difference in liver fat reduction between groups (β = 2.8; 95% confidence interval, -2.2 to 7.8; P = .30). In a fully adjusted regression model (adjusted for baseline measurement of the outcome plus age, sex, weight difference, and baseline weight), only weight loss was associated with a significant decrease in liver fat (β = 2; 95% confidence interval, 1.5-2.6; P = .03). Fecal samples from patients who received the synbiotic had higher proportions of Bifidobacterium and Faecalibacterium species, and reductions in Oscillibacter and Alistipes species, compared with baseline; these changes were not observed in the placebo group. Changes in the composition of fecal microbiota were not associated with liver fat or markers of fibrosis.

CONCLUSIONS

In a randomized trial of patients with NAFLD, 1 year of administration of a synbiotic combination (probiotic and prebiotic) altered the fecal microbiome but did not reduce liver fat content or markers of liver fibrosis. (ClinicalTrials.gov, Number: NCT01680640).

Adaptive statistical iterative reconstruction (ASIR) affects CT radiomics quantification in primary colorectal cancer

OBJECTIVES

To investigate whether adaptive statistical iterative reconstruction (ASIR), a hybrid iterative CT image reconstruction algorithm, affects radiomics feature quantification in primary colorectal cancer compared to filtered back projection. Additionally, to establish whether radiomics from single-slice analysis undergo greater change than those from multi-slice analysis.

METHODS

Following review board approval, contrast-enhanced CT studies from 32 prospective primary colorectal cancer patients were reconstructed with 20% ASIR level increments, from 0 to 100%. Radiomics analysis was applied to single-slice and multi-slice regions of interest outlining the tumour: 70 features, including statistical (first-, second- and high-order) and fractal radiomics, were generated per dataset. The effect of ASIR was calculated by means of multilevel linear regression.

RESULTS

Twenty-eight CT datasets were suitable for analysis. Incremental ASIR levels determined a significant change (p < 0.001) in most statistical radiomics features, best described by a simple linear relationship. First-order statistical features, including mean, standard deviation, skewness, kurtosis, energy and entropy, underwent a relatively small change in both single-slice and multi-slice analysis (median standardised effect size B = 0.08). Second-order statistical features, including grey-level co-occurrence and difference matrices, underwent a greater change in single-slice analysis (median B = 0.36) than in multi-slice analysis (median B = 0.13). Fractal features underwent a significant change only in single-slice analysis (median B = 0.49).

CONCLUSIONS

Incremental levels of ASIR affect significantly CT radiomics quantification in primary colorectal cancer. Second-order statistical and fractal features derived from single-slice analysis undergo greater change than those from multi-slice analysis.

KEY POINTS

• Incremental levels of ASIR determine a significant change in most statistical (first-, second- and high-order) CT radiomics features measured in primary colorectal cancer, best described by a linear relationship. • First-order statistical features undergo a small change, both from single-slice and multi-slice radiomics analyses. • Most second-order statistical features undergo a greater change in single-slice analysis than in multi-slice analysis. Fractal features are only affected in single-slice analysis.

Multiparametric MRI for early detection of diffuse liver disease: an interview with David Breen

David J Breen is Associate Professor of Radiology and previous Clinical Director of Radiology at University Hospital Southampton. His interests are in abdominal imaging and intervention, particularly of hepato-pancreato-biliary (HPB)and renal disease. He has a major interest in image-guided tumor ablation and improving outcomes from these procedures. He has previously served as Vice Chair of the NHS England Clinical Reference Group in Interventional Radiology and for the NIHR/NCRN Upper GI Clinical Studies Group.

Cross-sectional study of the provision of interventional oncology services in the UK

OBJECTIVE

To map out the current provision of interventional oncology (IO) services in the UK.

DESIGN

Cross-sectional multicentre study.

SETTING

All National Health Service (NHS) trusts in England and Scottish, Welsh and Northern Ireland health boards.

PARTICIPANTS

Interventional radiology (IR) departments in all NHS trusts/health boards in the UK.

RESULTS

A total of 179 NHS trusts/health boards were contacted. We received a 100% response rate. Only 19 (11%) institutions had an IO lead. 144 trusts (80%) provided IO services or had a formal pathway of referral in place for patients to a recipient trust. 21 trusts (12%) had plans to provide an IO service or formal referral pathway in the next 12 months only. 14 trusts (8%) did not have a pathway of referral and no plans to implement one. 70 trusts (39%) offered supportive and disease-modifying procedures. One trust had a formal referral pathway for supportive procedures. 73 trusts (41%) provided only supportive procedures (diagnostic or therapeutic). Of these, 43 (59%) had a referral pathway for disease-modifying IO procedures, either from a regional cancer network or through IR networks and 30 trusts (41%) did not have a referral pathway for disease-modifying procedures.

CONCLUSION

The provision of IO services in the UK is promising; however, collaborative networks are necessary to ensure disease-modifying IO procedures are made accessible to all patients and to facilitate larger registry data for research with commissioning of new services.

Percutaneous image-guided cryoablation of small renal masses

Renal cell carcinoma is a common malignancy with increasing incidence due to the incidental detection of non-symptomatic small renal masses on imaging. Management of these small tumors has evolved toward minimally invasive nephron-sparing techniques which include partial nephrectomy and image-guided ablation. Cryoablation and radiofrequency ablation are the most utilized ablation modalities with the former more suited for larger and central renal masses due to intra-procedural visualization of the ablation zone and reduced pelvicalyceal injury. In this article, we review the epidemiology and natural history of renal cell carcinoma, the role of biopsy, and the management options available-surgery, image-guided ablation, and active surveillance-with a focus on cryoablation. The clinical outcomes of the longer term maturing cryoablation data are discussed with reference to partial nephrectomy and radiofrequency ablation. Image-guided ablation has often been the management choice in patients deemed unfit for surgery; however, growing evidence from published series demonstrates image-guided ablation as a sound alternative treatment with equivalent oncological outcomes and minimal patient impact.

Image-guided ablation of primary liver and renal tumours

Image-guided ablation (IGA) techniques have evolved considerably over the past 20 years and are increasingly used to definitively treat small primary cancers of the liver and kidney. IGA is recommended by most guidelines as the best therapeutic choice for patients with early stage hepatocellular carcinoma (HCC)-defined as either a single tumour smaller than 5 cm or up to three nodules smaller than 3 cm-when surgical options are precluded, and has potential as first-line therapy, in lieu of surgery, for patients with very early stage tumours smaller than 2 cm. With regard to renal cell carcinoma, despite the absence of any randomized trial comparing the outcomes of IGA with those of standard partial nephrectomy, a growing amount of data demonstrate robust oncological outcomes for this minimally invasive approach and testify to its potential as a standard-of-care treatment. Herein, we review the various ablation techniques, the supporting evidence, and clinical application of IGA in the treatment of primary liver and kidney cancers.

Image-guided tumor ablation: standardization of terminology and reporting criteria--a 10-year update

Image-guided tumor ablation has become a well-established hallmark of local cancer therapy. The breadth of options available in this growing field increases the need for standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison among treatments that use different technologies, such as chemical (eg, ethanol or acetic acid) ablation, thermal therapies (eg, radiofrequency, laser, microwave, focused ultrasound, and cryoablation) and newer ablative modalities such as irreversible electroporation. This updated consensus document provides a framework that will facilitate the clearest communication among investigators regarding ablative technologies. An appropriate vehicle is proposed for reporting the various aspects of image-guided ablation therapy including classification of therapies, procedure terms, descriptors of imaging guidance, and terminology for imaging and pathologic findings. Methods are addressed for standardizing reporting of technique, follow-up, complications, and clinical results. As noted in the original document from 2003, adherence to the recommendations will improve the precision of communications in this field, leading to more accurate comparison of technologies and results, and ultimately to improved patient outcomes.

Understanding the current status of image-guided ablation for metastatic colorectal disease

Colorectal metastases to the liver are increasingly being detected and accurately characterized at an earlier stage and even at the subcentimeter level. The oncological case for surgical resection of this disease is widely accepted. The advent of smaller volume disease has encouraged the development of in situ ablative technologies over the last two decades and the oncological efficacy of these procedures has continued to improve through stepwise developments in ablation devices and image guidance. This article provides an overview of these techniques, currently available and future technologies, and the imaging findings encountered. It also sets out the current position image-guided ablation merits alongside chemotherapy and surgical resection. In selected cases ablation for colorectal metastases can produce oncological outcomes equivalent to surgery and critically with less morbidity in an increasingly older patient population. We examine whether with careful patient selection, optimal technology, meticulous technique, and diligent follow-up, consistently reproducible high quality outcomes will be achieved in the next few years.

Image-guided tumor ablation: standardization of terminology and reporting criteria--a 10-year update

Image-guided tumor ablation has become a well-established hallmark of local cancer therapy. The breadth of options available in this growing field increases the need for standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison among treatments that use different technologies, such as chemical (eg, ethanol or acetic acid) ablation, thermal therapies (eg, radiofrequency, laser, microwave, focused ultrasound, and cryoablation) and newer ablative modalities such as irreversible electroporation. This updated consensus document provides a framework that will facilitate the clearest communication among investigators regarding ablative technologies. An appropriate vehicle is proposed for reporting the various aspects of image-guided ablation therapy including classification of therapies, procedure terms, descriptors of imaging guidance, and terminology for imaging and pathologic findings. Methods are addressed for standardizing reporting of technique, follow-up, complications, and clinical results. As noted in the original document from 2003, adherence to the recommendations will improve the precision of communications in this field, leading to more accurate comparison of technologies and results, and ultimately to improved patient outcomes. Online supplemental material is available for this article .

Unusual radiological behaviour after cryoablation of renal cell carcinoma

Cryoablation has evolved into an effective treatment option in patients with renal tumours. The procedure is minimally invasive, and patients are often spared the morbidity and hospital stay that is often associated with open or partial nephrectomy. We present an unusual case of a 62-year-old male patient who underwent cryoablation of a renal cell carcinoma. He subsequently developed apparent exuberant local disease progression, which spontaneously regressed on follow-up CT imaging.

The clinical effectiveness and cost-effectiveness of ablative therapies in the management of liver metastases: systematic review and economic evaluation

BACKGROUND

Many deaths from cancer are caused by metastatic burden. Prognosis and survival rates vary, but survival beyond 5 years of patients with untreated metastatic disease in the liver is rare. Treatment for liver metastases has largely been surgical resection, but this is feasible in only approximately 20-30% of people. Non-surgical alternatives to treat some liver metastases can include various forms of ablative therapies and other targeted treatments.

OBJECTIVES

To evaluate the clinical effectiveness and cost-effectiveness of the different ablative and minimally invasive therapies for treating liver metastases.

DATA SOURCES

Electronic databases including MEDLINE, EMBASE and The Cochrane Library were searched from 1990 to September 2011. Experts were consulted and bibliographies checked.

REVIEW METHODS

Systematic reviews of the literature were undertaken to appraise the clinical effectiveness and cost-effectiveness of ablative therapies and minimally invasive therapies used for people with liver metastases. Studies were any prospective study with sample size greater than 100 participants. A probabilistic model was developed for the economic evaluation of the technologies where data permitted.

RESULTS

The evidence assessing the clinical effectiveness and cost-effectiveness of ablative and other minimally invasive therapies was limited. Nine studies of ablative therapies were included in the review; each had methodological shortcomings and few had a comparator group. One randomised controlled trial (RCT) of microwave ablation versus surgical resection was identified and showed no improvement in outcomes compared with resection. In two prospective case series studies that investigated the use of laser ablation, mean survival ranged from 41 to 58 months. One cohort study compared radiofrequency ablation with surgical resection and five case series studies also investigated the use of radiofrequency ablation. Across these studies the median survival ranged from 44 to 52 months. Seven studies of minimally invasive therapies were included in the review. Two RCTs compared chemoembolisation with chemotherapy only. Overall survival was not compared between groups and methodological shortcomings mean that conclusions are difficult to make. Two case series studies of laser ablation following chemoembolisation were also included; however, these provide little evidence of the use of these technologies in combination. Three RCTs of radioembolisation were included. Significant improvements in tumour response and time to disease progression were demonstrated; however, benefits in terms of survival were equivocal. An exploratory survival model was developed using data from the review of clinical effectiveness. The model includes separate analyses of microwave ablation compared with surgery and radiofrequency ablation compared with surgery and one of radioembolisation in conjunction with hepatic artery chemotherapy compared with hepatic artery chemotherapy alone. Microwave ablation was associated with an incremental cost-effectiveness ratio (ICER) of £3664 per quality-adjusted life-year (QALY) gained, with microwave ablation being associated with reduced cost but also with poorer outcome than surgery. Radiofrequency ablation compared with surgical resection for solitary metastases < 3 cm was associated with an ICER of -£266,767 per QALY gained, indicating that radiofrequency ablation dominates surgical resection. Radiofrequency ablation compared with surgical resection for solitary metastases ≥ 3 cm resulted in poorer outcomes at lower costs and a resultant ICER of £2538 per QALY gained. Radioembolisation plus hepatic artery chemotherapy compared with hepatic artery chemotherapy was associated with an ICER of £37,303 per QALY gained.

CONCLUSIONS

There is currently limited high-quality research evidence upon which to base any firm decisions regarding ablative therapies for liver metastases. Further trials should compare ablative therapies with surgery, in particular. A RCT would provide the most appropriate design for undertaking any further evaluation and should include a full economic evaluation, but the group to be randomised needs careful selection.

SOURCE OF FUNDING

Funding for this study was provided by the Health Technology Assessment programme of the National Institute for Health Research.

Guidelines for the management of gastroenteropancreatic neuroendocrine (including carcinoid) tumours (NETs)

These guidelines update previous guidance published in 2005. They have been revised by a group who are members of the UK and Ireland Neuroendocrine Tumour Society with endorsement from the clinical committees of the British Society of Gastroenterology, the Society for Endocrinology, the Association of Surgeons of Great Britain and Ireland (and its Surgical Specialty Associations), the British Society of Gastrointestinal and Abdominal Radiology and others. The authorship represents leaders of the various groups in the UK and Ireland Neuroendocrine Tumour Society, but a large amount of work has been carried out by other specialists, many of whom attended a guidelines conference in May 2009. We have attempted to represent this work in the acknowledgements section. Over the past few years, there have been advances in the management of neuroendocrine tumours, which have included clearer characterisation, more specific and therapeutically relevant diagnosis, and improved treatments. However, there remain few randomised trials in the field and the disease is uncommon, hence all evidence must be considered weak in comparison with other more common cancers.

Chemotherapy plus percutaneous radiofrequency ablation in patients with inoperable colorectal liver metastases

AIM: To access the efficacy of chemotherapy plus radiofrequency ablation (RFA) as one line of treatment in inoperable colorectal liver metastases.

METHODS: Eligible patients were included in three Phase II studies. In the first study percutaneous RFA was used first followed by 6 cycles of 5-fluorouracil, leucovorin and irinotecan combination (FOLFIRI) (adjunctive chemotherapy trial). In the other two, chemotherapy (FOLFIRI or 5-fluorouracil, leucovorin and oxaliplatin combination) up to 12 cycles was used first with percutaneous RFA offered to responding patients (primary chemotherapy trials).

RESULTS: Thirteen patients were included in the adjunctive chemotherapy trial and 17 in the other two. At inclusion they had 1-4 liver metastases (up to 6.5 cm in size). Two patients died during chemotherapy. All patients in the adjunctive chemotherapy trial and 44% in the primary chemotherapy studies had their metastases ablated. Median PFS and overall survival in the adjunctive study were 13 and 24 mo respectively while in the primary chemotherapy studies they were 10 and 21 mo respectively. Eighty one percent of the patients had tumour relapse in at least one previously ablated lesion.

CONCLUSION: Chemotherapy plus RFA in patients with low volume inoperable colorectal liver metastases seems safe and relatively effective. The high local recurrence rate is of concern.

Minimally invasive treatment of small renal tumors: trends in renal cancer diagnosis and management

Renal cell carcinoma is a common malignancy causing significant mortality. In recent years abdominal imaging, often for alternate symptomatology, has led the trend toward the detection and confirmation of smaller renal tumors. This has permitted the greater use of localized and nephron-sparing techniques including partial nephrectomy and image-guided ablation. This article aims to review the current role of image-guided biopsy and ablation in the management of small renal tumors. The natural history of renal cell carcinoma, the role of renal biopsy, the principles and procedural considerations of thermal energy ablation, and the oncological outcomes of these minimally invasive treatments are discussed and illustrated with cases from the authors' institution. Image-guided ablation, in particular, has changed the treatment paradigm and, by virtue of its increasingly evident efficacy and low morbidity, now favors the treatment of smaller tumors in patients previously unfit for surgery.

Long-term results of percutaneous radiofrequency ablation of unresectable colorectal hepatic metastases: final outcomes

INTRODUCTION

Percutaneous radiofrequency ablation (PcRFA) provides alternative means of treating patients with unresectable colorectal liver metastases. We previously reported our initial experience in 30 patients treated with PcRFA. We present the final long-term results in these 30 patients.

METHODS

The final outcome of the 30 patients treated with PcRFA is reported, 30 months following the initial results published in 2004.

RESULTS

Thirty patients (21 males and 9 females), median age 74.5 (44-85) years, underwent PcRFA for 57 lesions in 60 sessions. The final results in this cohort of patients are reported: 28 dead and 2 lost to follow-up. Median follow-up was 22 (3-53) months. Median size was 31 (8-70) mm. Nineteen lesions required repeat PcRFA. Median ablation time per lesion was 12 (4.5-36) min. Eleven patients received chemotherapy pre-PcRFA and 15 received chemotherapy post-PcRFA. Three patients went on to have limited hepatectomies. Complications occurred in 3 (5%) and median hospital stay was 1 (1-7) day. The median hepatic disease-free survival was 12 (95% CI 6.1-17.9) months and actuarial survival was 23.2 (95% CI 18.5-27.8) months.

CONCLUSION

PcRFA is safe and associated with increased disease-free and overall survival in patients with unresectable colorectal hepatic metastases.

Management of renal tumors by image-guided radiofrequency ablation: experience in 105 tumors

Aims

In this article we present our experience with radiofrequency ablation (RFA) in the treatment of 105 renal tumors.

Materials and Methods

RFA was performed on 105 renal tumors in 97 patients, with a mean tumor size of 32 mm (11–68 mm). The mean patient age was 71.7 years (range, 36–89 years). The ablations were carried out under ultrasound (n = 43) or CT (n = 62) guidance. Imaging follow-up was by contrast-enhanced CT within 10 days and then at 6-monthly intervals. Multivariate analysis was performed to determine variables associated with procedural outcome.

Results

Eighty-three tumors were completely treated at a single sitting (79%). Twelve of the remaining tumors were successfully re-treated and a clinical decision was made not to re-treat seven patients. A patient with a small residual crescent of tumor is under follow-up and may require further treatment. In another patient, re-treatment was abandoned due to complicating pneumothorax and difficult access. One patient is awaiting further re-treatment. The overall technical success rate was 90.5%. Multivariate analysis revealed tumor size to be the only significant variable affecting procedural outcome. (p = 0.007, Pearson χ²) Five patients had complications. There have been no local recurrences.

Conclusion

Our experience to date suggests that RFA is a safe and effective, minimally invasive treatment for small renal tumors.

Is routine magnetic resonance imaging justified for the early detection of resectable liver metastases from colorectal cancer?

PURPOSE

This study was designed to determine whether routine follow-up by magnetic resonance imaging improves the detection of resectable liver metastases from colorectal cancer and patients' survival.

METHODS

Patients who underwent curative surgery for colorectal cancer were included in a program of liver surveillance by routine magnetic resonance imaging, in addition to the standard follow-up protocol consisting of clinical examination and biochemical tests. The median follow-up was 41 (interquartile range, 30-53) months, with a median magnetic resonance imaging surveillance period of 20 (interquartile range, 12-27) months. Cases were analyzed for mode of diagnosis, resectability, and overall survival.

RESULTS

Liver metastases were found in 37 (13 percent) of 293 patients studied. Magnetic resonance imaging diagnosed hepatic metastases with 84 percent sensitivity and 90 percent specificity. In 28 (76 percent) patients, carcinoembryonic antigen and/or liver function tests were abnormally elevated and 5 patients (14 percent) were symptomatic. Hepatic resection was possible in only nine patients (24 percent). Magnetic resonance imaging detected all resectable cases, whereas traditional follow-up would have missed three (33 percent) cases suitable for surgery.

CONCLUSIONS

Although magnetic resonance imaging surveillance increased the number of patients suitable for liver resection by 50 percent, these represented only 1 percent of the patients included in the study. Whether these results are enough to justify the allocation of expensive resources is controversial.

Routine follow-up by magnetic resonance imaging does not improve detection of resectable local recurrences from colorectal cancer

OBJECTIVE

To determine if routine follow-up by magnetic resonance imaging (MRI) improves the detection of resectable local recurrences from colorectal cancer.

SUMMARY BACKGROUND DATA

Surgical treatment offers the best prospect of survival for patients with recurrent colorectal cancer. Unfortunately, most cases are often diagnosed at an unresectable stage when traditional follow-up methods are used. The impact of MRI surveillance on the early diagnosis of local recurrences has yet to be ascertained.

METHODS

Patients who underwent curative surgery for rectal and left-sided colon tumors were included in a program of pelvic surveillance by routine MRI, in addition to the standard follow-up protocol. Cases were then analyzed for mode of diagnosis, resectability, and overall survival.

RESULTS

Pelvic recurrence was found in 30 (13%) of the 226 patients studied. MRI detected 26 of 30 (87%) and missed 4 of 30 (13%) cases with local recurrence. Of the latter, 3 were anastomotic recurrences. In 28 (14%) patients, local recurrence was suspected by an initial MR scan but cleared by subsequent MRI or CT-guided biopsy. Recurrent pelvic cancer was diagnosed by MRI with 87% sensitivity and 86% specificity. In 19 (63%) cases, CEA was abnormally elevated, and 9 patients (30%) were symptomatic. Surgical resection was possible in only 6 patients (20%). There was no difference between MRI and conventional follow-up tests in their ability to detect cases suitable for surgery.

CONCLUSIONS

Pelvic surveillance by MRI is not justified as part of the routine follow-up after a curative resection for colorectal cancer and should be reserved for selectively imaging patients with clinical, colonoscopic, and/or biochemical suspicion of recurrent disease.

Percutaneous radiofrequency ablation of colorectal hepatic metastases - initial experience. An adjunct technique to systemic chemotherapy for those with inoperable colorectal hepatic metastases

BACKGROUND AND AIM

Most patients with hepatic metastases from colorectal carcinoma are unsuitable for resection. Radiofrequency ablation (RFA) has been applied to such lesions at laparotomy. This study aimed to evaluate the less invasive approach of percutaneous RFA.

METHOD

Patients with unresectable liver metastases identified on cross-sectional imaging were considered for percutaneous RFA either alone or in combination with systemic chemotherapy. Subjects with >6 lesions or lesions of maximum size >70 mm were excluded. Percutaneous RFA was applied under sedation and radiological guidance (CT/US). Treatment effect was determined by follow-up imaging. Actuarial survival was calculated by the Kaplan-Meier analysis.

RESULTS

Thirty patients (21 males), median age 74.5 years (range 44-85 years), underwent percutaneous RFA to 56 lesions during 54 treatment sessions. The median size of lesion was 30 mm (range 8-70 mm). Fifteen lesions were treated more than once because of recurrence or incomplete ablation. The median ablation time per lesion was 12 min (range 4.5-36 min). Eleven patients had pre-procedural chemotherapy and 15 patients received chemotherapy after treatment. There was minimal associated morbidity (5.6% of treatments). Median hospital stay per treatment was 1 day (range 1-7). Median actuarial survival from the date of first percutaneous RFA was 22 months (95% CI 12.9-31.1 months). Eleven patients were alive at the time of data collection.

CONCLUSION

Percutaneous RFA is a safe, well-tolerated intervention for unresectable hepatic metastases which can be repeated, if required. The technique may be associated with prolonged survival in this selected group of subjects. Future studies should consider the role of percutaneous RFA either in place of or as an adjunct to palliative chemotherapy.

Intrahepatic arterioportal shunting and anomalous venous drainage: understanding the CT features in the liver

The increased use of high-contrast volume, arterial-phase studies of the liver has demonstrated the frequent occurrence of arterioportal shunts within both the cirrhotic and non-cirrhotic liver. This article sets out to explain the underlying microcirculatory mechanisms behind these commonly encountered altered perfusion states. Similarly, well-recognised portal perfusion defects occur around the perifalciform and perihilar liver and are largely caused by anomalous venous drainage via the paraumbilical and parabiliary venous systems. The underlying anatomy will be discussed and illustrated. These vascular anomalies are all caused by or result in diminished portal perfusion and are often manifest in the setting of portal venous thrombosis. The evolving concept of zonal re-perfusion following portal vein thrombosis will be discussed.

Percutaneous thrombin injection for the treatment of a post-pancreatitis pseudoaneurysm

Visceral artery pseudoaneurysms are often treated surgically or by transcatheter embolisation. We report a case of a pseudoaneurysm in a patient with chronic pancreatitis, which was successfully occluded by percutaneous injection of thrombin into the pseudoaneurysmal sac as a first-line management.

Technical aspects and complications of laparoscopic banding for morbid obesity—a radiological perspective

Morbid obesity is a significant clinical problem in the western world. Various surgical restrictive procedures have been described as an aid to weight reduction when conservative treatments fail. Adjustable laparoscopic gastric banding (LAPBAND) has been popularized as an effective, safe, minimally invasive, yet reversible technique for the treatment of morbid obesity. Radiological input is necessary in the follow-up of these patients and the diagnosis of complications peculiar to this type of surgery. In this review we will highlight the technical aspects of radiological follow-up and the lessons learnt over the last 5 years.

Early experience with percutaneous radiofrequency ablation of small solid renal masses

OBJECTIVE

Incidental small renal-cell masses are often seen in elderly patients with significant comorbidity who are unfit to undergo major surgery. This study was conducted to determine the safety and efficacy of percutaneous imaging-guided radiofrequency ablation in the management of small solid renal masses, almost all of which are renal cell cancers.

CONCLUSION

Early experience suggests that radiofrequency ablation is a safe, well-tolerated, and minimally invasive therapy for patients with solid renal masses. In the era of nephron-sparing surgery, radiofrequency ablation may have a role in the management of small problematic renal masses.

Radiofrequency thermal ablation of a metastatic lung nodule

Pulmonary metastases are a common finding in patients with colonic adenocarcinoma. We report the treatment of a metastatic lung nodule with radiofrequency (RF) ablation under CT guidance. This case illustrates the use of RF ablation in a patient in whom surgical resection was no longer possible and where chemotherapy was unlikely to produce benefit. This technique may offer a viable method of cytoreduction when other treatments have not succeeded.

The impact of new technology on surgery for colorectal cancer

Advances in technology continue at a rapid pace and affect all aspects of life, including surgery. We have reviewed some of these advances and the impact they are having on the investigation and management of colorectal cancer. Modern endoscopes, with magnifying, variable stiffness and localisation capabilities are making the primary investigation of colonic cancer easier and more acceptable for patients. Imaging investigations looking at primary, metastatic and recurrent disease are shifting to digital data sets, which can be stored, reviewed remotely, potentially fused with other modalities and reconstructed as 3 dimensional (3D) images for the purposes of advanced diagnostic interpretation and computer assisted surgery. They include virtual colonoscopy, trans-rectal ultrasound, magnetic resonance imaging, positron emission tomography and radioimmunoscintigraphy. Once a colorectal carcinoma is diagnosed, the treatment options available are expanding. Colonic stents are being used to relieve large bowel obstruction, either as a palliative measure or to improve the patient’s overall condition before definitive surgery. Transanal endoscopic microsurgery and minimally invasive techniques are being used with similar outcomes and a lower mortality, morbidity and hospital stay than open trans-abdominal surgery. Transanal endoscopic microsurgery allows precise excision of both benign and early malignant lesions in the mid and upper rectum. Survival of patients with inoperable hepatic metastases following radiofrequency ablation is encouraging. Robotics and telemedicine are taking surgery well into the 21^st century. Artificial neural networks are being developed to enable us to predict the outcome for individual patients. New technology has a major impact on the way we practice surgery for colorectal cancer.

Symptomatic malignant gastroesophageal anastomotic leak: management with covered metallic esophageal stents

OBJECTIVE

Gastroesophageal anastomotic leak after cancer resection has a mortality rate of up to 60% and significant morbidity, whatever the mode of treatment. We assessed the efficacy of esophageal stenting as a therapeutic option to reduce the mortality and morbidity associated with symptomatic intrathoracic anastomotic leakage.

SUBJECTS AND METHODS

During a 52-month period, 14 patients had placement of stents for clinically significant postoperative leaks: 10 patients had an esophagogastrectomy and four patients had a total gastrectomy with esophagojejunal anastomosis. Thirteen of 14 patients had tumors that were histologically staged as T3 N1 M0 or worse. Significant anastomotic leaks were revealed by a contrast-enhanced study at 3-28 days after surgery. Stents were inserted in patients in whom the leakage was debilitating or initial conservative treatment had failed. Stenting outcome in terms of clinical and radiologic healing, hospital stay, survival, and complications was assessed.

RESULTS

No procedural morbidity or 30-day mortality occurred. Immediate postprocedural leak occlusion was obtained in all patients. Clinical healing of the leak occurred in 13 (92.8%) of 14 patients, with a median healing time of 6 days. Of the 13 patients, healing occurred within 10 days in 10 patients (76.9%). Eight of these 10 early closures received a knitted nitinol stent (p = 0.02). One patient (7%) died as a consequence of leakage at 135 days. Median survival for all 14 patients was 11 months (Kaplan-Meier method). Complications included five episodes of food blockages in three patients, which required endoscopic clearance, and one case of stent-related upper gastrointestinal hemorrhage. No patients developed anastomotic stricture or occlusive epithelial hyperplasia.

CONCLUSION

Covered esophageal stenting appears to reduce the mortality and morbidity of symptomatic anastomotic leakage after surgery for gastroesophageal cancer. Knitted nitinol stents may be best suited to this purpose.

Testicular microlithiasis: prevalence and tumor risk in a population referred for scrotal sonography

OBJECTIVE

Considerable accrued evidence points to an association between testicular microlithiasis, intratubular germ cell neoplasia, and testicular tumor. This study assesses both the prevalence of testicular microlithiasis revealed on sonography in a referred population and the concurrent tumor risk.

MATERIALS AND METHODS

Over a 32-month period (April 1996 through November 1998), 4892 scrotal sonographic examinations were performed in 4819 patients at four referral centers. All patients underwent high-resolution (7- to 10-MHz) imaging. Using a computerized word search (n = 4102; testicular microlithiasis, calcification, microliths, calcific foci, tumor, neoplasm, cancer, hyperecho, hypoecho, heterogen, and carcinoma) and manual retrieval (n = 790), cases of tumor, testicular microlithiasis (>5 microliths per sonogram), and testicular microlithiasis plus tumor were pulled and retrospectively reviewed. The presence and type of tumor were confirmed at histology after orchidectomy.

RESULTS

Fifty-four tumors were found among 4892 scrotal sonograms (28 seminomas, 14 teratomas, 8 mixed germ cell tumors, 2 Leydig cell tumors, and 2 non-Hodgkin's lymphomas). Testicular microlithiasis was present in 33 patients, giving a prevalence of 0.68%. Concurrent tumor and testicular microlithiasis were detected in seven patients, a relative risk of tumor in testicular microlithiasis was 21.6-fold (95% confidence limits: 10. 6-fold, 44.2-fold). In one patient with testicular microlithiasis, a previous orchidectomy for mixed germ cell tumor had been performed (not included in the relative risk calculation).

CONCLUSION

In a referred population of 4819 patients the prevalence of testicular microlithiasis was 0.68% and the relative risk of concurrent tumor was 21.6-fold. Sonographic surveillance of testicular microlithiasis cases for tumor is mandatory.

The clinical utility of spiral CT cholangiography

Spiral CT cholangiography has received little attention, yet in a single breath-hold spiral and with limited manipulation at the workstation it can yield high resolution images of the biliary tract. In addition it can clearly demonstrate periampullary detail and contribute some dynamic information regarding biliary excretion. The clinical utility of this technique is illustrated and discussed. Breen, D. J., Nicholson, A. A. (2000). Clinical Radiology55, 733-739.

Rapid fibrin D-dimer tests for deep venous thrombosis: factors affecting diagnostic utility

Measurement of fibrin D-dimer may be a useful diagnostic test to exclude a diagnosis of deep venous thrombosis (DVT) in the emergency department setting. However, the specific assay format may influence its sensitivity and ultimate clinical utility. We tested samples from 200 patients under evaluation for DVT using three fibrin D-dimer assays: the SimpliRED whole blood agglutination assay, a latex agglutination assay, and the Dimertest EIA. Latex agglutination assays were performed in both a specialized laboratory and a routine laboratory. The negative predictive value for all tests was > 90%. The sensitivity of the SimpliRED assay was similar to that of the latex assay. The sensitivity of the latex assay was significantly lower when performed by generalist laboratory technologists. Thus, while D-dimer may be a useful test for the exclusion of DVT, subjective endpoint latex agglutination assays should be performed only by appropriately trained personnel.

Diagnostic accuracy of helical CT for detection of blunt bowel and mesenteric injuries

OBJECTIVE

To determine the diagnostic accuracy of helical computed tomography (CT) in the detection of blunt bowel and mesenteric injury in a clinical setting.

MATERIALS AND METHODS

We evaluated the helical CT and surgical findings in 31 patients with blunt abdominal trauma. Nineteen patients had surgically proven bowel and/or mesenteric injury, and 12 patients had no bowel or mesenteric injury at laparotomy. The CT scans were assessed by three observers in consensus and were graded as showing no injury, minor bowel or mesenteric injury (not requiring urgent surgery), or major bowel or mesenteric injury (requiring immediate surgery). The CT diagnoses were compared with the surgical findings.

RESULTS

In the 19 cases of surgically proven bowel injury, CT had an accuracy of 84% (26/31), specificity 84% (16/19), and negative predictive value 89% (16/18) for diagnosis of bowel injury. CT correctly differentiated minor from major bowel injuries in eight of 12 cases (75%). For the 13 cases of mesenteric injury, the accuracy of CT diagnosis was 77% (24/31), specificity 67% (12/18), and negative predictive value 93% (12/13) for diagnosis of mesenteric injury. The CT findings allowed correct differentiation of minor from major mesenteric injuries in seven of 13 cases (54%).

CONCLUSION

Helical CT is moderately accurate and has a high negative predictive value in detecting bowel and mesenteric injuries after blunt trauma. Helical CT is not highly accurate in predicting the severity of injury or need for urgent surgery.

Blunt bowel and mesenteric injury: diagnostic performance of CT signs

PURPOSE

Our goal was to determine the sensitivity and specificity of various CT signs of blunt bowel and mesenteric injury.

METHOD

The CT findings of 31 patients with blunt abdominal trauma were retrospectively assessed by three observers in consensus. All patients had laparotomy within 24 h of CT. The study group consisted of 19 patients with surgically proven bowel and/or mesenteric injury. The control group consisted of 12 traumatized patients who had no bowel or mesenteric injury. The CT signs assessed were presence, location, and extent of intraperitoneal fluid, extraluminal air, bowel wall thickening, bowel wall discontinuity, mesenteric streaking, and mesenteric hematoma.

RESULTS

In the 12 cases of bowel injury (9 transmural injury, 3 partial thickness injury), the CT sign of bowel wall thickening had sensitivity of 50% and specificity of 84% and the CT sign of bowel wall discontinuity had sensitivity of 58% and specificity of 95%. Extraluminal air was a specific but relatively insensitive sign of transmural bowel injury (sensitivity 44%, specificity 100%). In the 13 patients with mesenteric injuries, the CT sign of mesenteric hematoma had sensitivity of 54% and specificity of 94%. Isolated mesenteric streaking was a less specific sign of mesenteric injury (sensitivity 77%, specificity 44%). The finding of peritoneal fluid with no visible solid organ injury was a useful sign of bowel or mesenteric injury, occurring in 11 of 19 (58%) study patients and none of the controls (p < 0.001).

CONCLUSION

Bowel wall thickening, bowel wall discontinuity, extraluminal air, and mesenteric hematoma are reasonably specific CT signs of bowel and mesenteric injury following blunt abdominal trauma. The presence of a moderate to large volume of intraperitoneal fluid without visible solid organ injury is an important sign of bowel or mesenteric injury.

Fluoroscopically-guided retrieval of ureteric stents

Percutaneous fluoroscopically-guided retrieval of seven dysfunctional ureteric stents was performed in five patients (four male, one female) over an 18 month period. The technical aspects of the procedure are discussed and the preferred method using rigid forceps is described.

[Analgesics; the use of aspirin in dogs; effects of tablet type and food intake on plasma salicylate level]

Administration of acetylsalicylic acid (aspirin) in the dog may cause gastric mucosal damage. Enteric-coated tablets protect the canine stomach during oral aspirin medication. A therapeutic plasma salicylate concentration can be attained using enteric-coated aspirin tablets at a dosage of 25 mg/kg TID. In a series 4 of experiments using adult beagle and large mixed breed dogs and two types enteric-coated tablets, the influence of food intake on the plasma salicylate concentration was studied. Tablets were administered with 8h intervals and food intake was either once daily or three time daily with 8h intervals. Plasma salicylate concentrations were also studied during fasting. It is concluded that, when using enteric-coated tablets, the plasma salicylate concentration in the dog after oral medication is strongly influenced by the aspirin dosage, the tablet type and the feeding pattern. Large enteric-coated tablets may accumulate in the stomach over several days and are not suitable for use in the dog. The gastric accumulation is caused by the enteric-coating of the large tablets and not by the aspirin medication.

Titanium lines: a manifestation of metallosis and tissue response to titanium alloy megaprostheses at the knee

Titanium alloy, in its Ti-318 (Ti-A16-V4) format, is a widely used material for orthopaedic implants. However, it has frequently been reported as causing black staining of the periprosthetic tissues as a result of debris from metallic wear. This process of metallosis has been implicated in implant failure. We report three cases in which titanium alloy prostheses for primary bone tumours at the knee have caused the formation of fluid-filled cysts containing metallic debris. The cysts result in radiological appearances which may mimic soft tissue tumour recurrence and also contribute to post-operative failure of the extensor mechanism of the knee.

Invasive aspergilloma of the skull base

Aspergillus infection originating in the nasal cavity or paranasal sinuses is a rare cause of benign, locally invasive disease affecting the skull base. We describe a case in which extensive disease led to bilateral proptosis and invasion of the anterior cranial fossa.