Renal Cell Carcinoma: The Evolving Role of Imaging in the 21st Century.

Kidney lesions are commonly an incidental finding on cross sectional studies carried out for a variety of reasons. The detection of renal cell carcinoma (RCC) has increased accordingly. There are a variety of different contrast-enhanced CT imaging protocols that have been developed to help diagnose and stage RCC. More recently, renal MRI and contrast-enhanced ultrasound have also been used as problem-solving tools. This paper describes the epidemiology of RCC and the role of imaging in diagnosis and follow-up.

Percutaneous Renal Ablation.

Incidental small renal cell cancers are increasingly being diagnosed on cross-sectional imaging. This review article describes the indications for percutaneous ablation of small renal cell cancers, choice of ablation technologies and imaging follow-up.

Extravascular findings during upper limb computed tomographic angiography focusing on undiagnosed malignancy.

BACKGROUND: Computer tomography angiography (CTA) has been an established method for diagnostic vascular disease of lower limbs. Recently, the method is widely used for diagnosis of vascular pathologies in the upper limbs too. It also has increased the possibilities of this scans being reviewed by no specially trained radiologists. This increases the risk of incidental non vascular findings to be missed or misinterpreted. The study is focusing in the frequency of extravascular incidental finding (EVIF) and highlights the importance for both the reporting radiologist and the referring physician recognizing the frequency of EVIFs. AIM: To analyse the frequency of EVIF identified on computed angiography (CT) of the upper limb. METHODS: A total of 1383 CT angiographic studies of the peripheral arterial system were performed between August 2015 and August 2017. All upper limb CTAs (n = 79) were retrospectively reviewed for the presence of non-vascular incidental findings within the chest, abdomen/pelvis, musculoskeletal system or head and neck. These EVIFs were subsequently grouped into 3 categories based on clinical significance. EVIFs of immediate clinical relevance were included in category A, findings considered indeterminate but most likely benign were placed in category B, while incidental findings of no clinical significance were included in category C. RESULTS: Complete imaging datasets were available in 74/79 (93.7%). Patient demographics included 39 (52.7%) females and 35 (47.2%) males with a mean age of 59 ± 19.5 years (range 19-93 years). A total of 153 EVIFs were reported in 52 patients (70.3%). Of these, 44 EVIFs (28.7%) were found in the chest, 83 (54.2%) in the abdomen, 14 (9.2%) in the musculoskeletal system and 9 (5.8%) in the head and neck. Thirteen EVIFs (8.4%) identified in 11 patients were noted to be of immediate clinical significance (Category A), 50 EVIFs (32.3%) were identified in 20 patients and were considered indeterminate but most likely benign, while the remaining 91 EVIFs (59.5%) identified in 21 patients were determined to be of no clinical significance (Category C). One index case of malignancy (1.3%) and four cases of new disseminated metastatic disease (5.4%) were identified. CONCLUSION: Our study of upper limb CTA examinations demonstrated a frequency of 8.4% for extravascular incidental findings of immediate clinical significance. We highlight the importance for both the reporting radiologist and the referring physician of the need to recognize the frequency with which EVIFs are identified in the upper limb peripheral arterial system and of the necessity for further clinical and imaging work-up.

Percutaneous Radiofrequency Ablation Versus Robotic-Assisted Partial Nephrectomy for the Treatment of Small Renal Cell Carcinoma.

INTRODUCTION: The authors compared the oncologic outcomes of radiofrequency ablation (RFA) with robotic-assisted partial nephrectomy (RPN) for the treatment of T1 stage renal cell carcinoma (RCC). MATERIALS AND METHODS: This was a retrospective data analysis of a high-volume single tertiary centre. Patients were treated with RFA or RPN following multidisciplinary decision making. Only histologically proven RCCs were included. Baseline demographics were collected, and PADUA scores of tumour features were calculated to standardize baseline anatomy. Peri-operative complications, kidney function and oncological outcomes were compared. RESULTS: Sixty-three cases were included in each group. Baseline renal function was poorer in RFA, and 16/63 RFA patients had tumours in single kidneys compared to 1/63 RPN cases (p < 0.001). Length of stay was shorter in RFA (1 vs. 3 days, p < 0.0001). Post-procedure renal function decline at 30 days was significantly less in RFA [(-0.8) ± 9.6 vs. (-16.1) ± 19.5 mls/min/1.73 m2; p < 0.0001]. More minor complications were recorded in RPN (10/63 vs. 4/63, p = 0.15), but local recurrence was numerically higher in RFA (6/63 vs. 1/63, p = 0.11). Disease-free survival (DFS) was not significantly different (adjusted HR = 0.6, 95 % Cl 0.1-3.7; p = 0.60). Increasing tumour size was an independent predictor of local recurrence (adjusted HR = 1.7; 95 % Cl 1.1-2.6 per cm; p = 0.02). CONCLUSIONS: Both RPN and RFA offer very good oncological outcomes for the treatment of T1 RCC with low peri-operative morbidity and similar oncologic outcomes. RFA demonstrated fewer peri-operative complications and better preservation of renal function, whereas RPN had an insignificantly lower local recurrence rate. RFA should be offered alongside RPN for selected cases.

Renal Angiomyolipoma: Mid- to Long-Term Results Following Embolization with Onyx.

PURPOSE: Percutaneous transcatheter embolization is currently the preferred treatment for ruptured or enlarging renal angiomyolipoma (AML), although the optimum choice of embolic material has not yet been established. We present mid- to long-term outcomes following embolization of AMLs with Onyx. MATERIALS AND METHODS: Ten AMLs in seven patients (including two with tuberous sclerosis) were embolized with Onyx. Patients were followed-up clinically, with tumour size and renal function measured pre- and post-procedure. RESULTS: Mean pre-treatment AML size was 63.4 mm (range 42-100). Mean clinical follow-up was 431.4 days (range 153-986) and imaging follow-up 284.2 days (range 30-741). There was no haemorrhage from treated lesions within the follow-up period. Of patients who had cross-sectional imaging pre- and post-procedure, mean decrease in AML size of 22 mm was seen after Onyx embolization (p = 0.0058, 95 % CI 9.13-34.87). No significant difference between serum creatinine was seen pre- and post-procedure (p = 0.54, 95 % CI 8.63-4.85). CONCLUSIONS: Onyx embolization of renal AMLs is effective in the medium to long term, with theoretical benefits in safety and durability of result.

Radiological Evaluation of Abdominal Endovascular Aortic Aneurysm Repair.

Endovascular aortic aneurysm repair (EVAR) is an alternative to open surgical repair of aortic aneurysms offering lower perioperative mortality and morbidity. As experience increases, clinicians are undertaking complex repairs with hostile aortic anatomy using branched or fenestrated devices or extra components such as chimneys to ensure perfusion to visceral branch vessels whilst excluding the aneurysm. Defining the success of EVAR depends on both clinical and radiographic criteria, but ultimately depends on complete exclusion of the aneurysm from the circulation. Aortic stent grafts are monitored using a combination of imaging modalities including computed tomography angiography (CTA), ultrasonography, magnetic resonance imaging, plain films, and nuclear medicine studies. This article describes when and how to evaluate aortic stent grafts using each of these modalities along with the characteristic features of several of the main stent grafts currently used in clinical practice. The commonly encountered complications from EVAR are also discussed and how they can be detected using each imaging modality. As the radiation burden from serial follow up CTA imaging is now becoming a concern, different follow-up imaging strategies are proposed depending on the complexity of the repair and based on the relative merits and disadvantages of each imaging modality.