Safety of percutaneous renal cryoablation: an international multicentre experience from the EuRECA retrospective percutaneous database.

OBJECTIVE: To investigate the safety profile of percutaneous cryoablation of renal tumours < 7 cm, utilising data extracted from an international multicentre registry. MATERIALS AND METHODS: A retrospective review of all immediate and delayed complications from a multicentre database was performed and was categorised according to the Clavien-Dindo classification. Statistical analysis was performed for both overall complications (all Clavien-Dindo) and major complications (Clavien-Dindo 3 to 5). The following criteria were identified as potential predictive factors for complications: centre number, modality of image guidance, tumour size (≤ 4 cm vs. > 4 cm), number of tumours treated in the same session (1 vs. > 1) and tumour histology. RESULTS: A total of 713 renal tumours underwent ablation in 647 individual sessions. In 596 of the cases, one tumour was treated; in the remaining 51 cases, several tumours were treated per session. Mean lesion size was 2.8 cm. Fifty-four complications (Clavien-Dindo 1 to 5) occurred as a result of the 647 procedures, corresponding to an overall complication rate of 8.3%. The most frequent complication was bleeding (3.2%), with 9 cases (1.4%) requiring subsequent treatment. The rate of major complication was 3.4%. The only statistically significant prognostic factor for a major complication was a tumour size > 4 cm. CONCLUSION: Percutaneous renal cryoablation is associated with a low rate of complications. Tumours measuring more than 4 cm are associated with a higher risk of major complications. KEY POINTS: • Percutaneous kidney cryoablation has a low rate of complications. • Bleeding is the most frequent complication. • A tumour size superior to 4 cm is a predictive factor of major complication.

Adaptive statistical iterative reconstruction improves image quality without affecting perfusion CT quantitation in primary colorectal cancer.

OBJECTIVES: To determine the effect of Adaptive Statistical Iterative Reconstruction (ASIR) on perfusion CT (pCT) parameter quantitation and image quality in primary colorectal cancer. METHODS: Prospective observational study. Following institutional review board approval and informed consent, 32 patients with colorectal adenocarcinoma underwent pCT (100 kV, 150 mA, 120 s acquisition, axial mode). Tumour regional blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) were determined using identical regions-of-interests for ASIR percentages of 0%, 20%, 40%, 60%, 80% and 100%. Image noise, contrast-to-noise ratio (CNR) and pCT parameters were assessed across ASIR percentages. Coefficients of variation (CV), repeated measures analysis of variance (rANOVA) and Spearman' rank order correlation were performed with statistical significance at 5%. RESULTS: With increasing ASIR percentages, image noise decreased by 33% while CNR increased by 61%; peak tumour CNR was greater than 1.5 with 60% ASIR and above. Mean BF, BV, MTT and PS differed by less than 1.8%, 2.9%, 2.5% and 2.6% across ASIR percentages. CV were 4.9%, 4.2%, 3.3% and 7.9%; rANOVA P values: 0.85, 0.62, 0.02 and 0.81 respectively. CONCLUSIONS: ASIR improves image noise and CNR without altering pCT parameters substantially.

Imaging appearances at follow-up after image-guided solid-organ abdominal tumour ablation.

The role of minimally invasive, locoregional therapies in cancer is increasingly driven by the detection of small asymptomatic disease either incidentally or under surveillance for a known primary malignancy. Percutaneous image-guided ablation has become established as a parenchyma-sparing tool in the management of small volume primary and metastatic disease in the liver as well as solitary renal masses. As ablation is non-extirpative, post-ablation imaging is critical for the assessment of treatment completion, recurrence, and complications. Within established regional cancer networks, understanding of normal post-ablation imaging appearances is essential for the early identification of primary treatment failure or local recurrence, which may be amenable to repeat treatment. We provide an imaging primer of two common ablation sites - kidney and liver - focusing on normal appearances and appreciation of local disease progression.

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.

Immediate and long-term CT appearances following radiofrequency ablation of renal tumours.

The incidence of renal cell carcinoma is increasing and image-guided radiofrequency ablation (RFA) is emerging as a safe and effective primary treatment. Therefore, it is essential for radiologists to appreciate the varied computed tomography (CT) imaging features following RFA. Prompt recognition of residual or recurrent tumour is crucial in facilitating timely re-treatment where necessary. Conversely, involuting, completely ablated lesions may be mistaken for residual disease. Using examples from experience of treating 105 renal tumours over a 5-year period, the spectrum of post-RFA CT appearances will be illustrated.

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.

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.

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.

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.

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.

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.

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.