Hyperechoic renal masses Jean-Yves Meuwly, MD Department of Diagnostic and Interventional Radiology, University Hospital Lausanne, Switzerland Department of Diagnostic and Interventional Radiology
Renal masses in the adult patient Increased frequency of discovery because increasing use of imaging modalities Increased incidence of renal cell carcinoma Substantial fraction of solid renal masses are benign 25% of masses smaller than 3 cm 30% of masses smaller than 2 cm 40% of masses smaller than 1 cm 1. Israel GM, Bosniak MA. How I do it: evaluating renal masses. Radiology 2005; 236:441-450. 2. Silverman SG, Gan YU, Mortele KJ, Tuncali K, Cibas ES. Renal masses in the adult patient: the role of percutaneous biopsy. Radiology 2006; 240:6-22. Department of Diagnostic and Interventional Radiology
Benign solid tumors Angiomyolipoma Most common benign solid renal tumor Almost always diagnosed by using imaging alone Hypervascular and contain fat Oncocytoma Presence of a prominent central scar Spoke-wheel pattern on angiographic images Metanephric adenoma Leiomyoma Adenoma Department of Diagnostic and Interventional Radiology
US pattern Angiomyolipoma Well defined hyperechoic mass Small to huge size Hypervascular when large CT pattern Hypodense on non-enhanced scan in 95.5% of cases Homogeneous enhancement Prolonged enhancement pattern MRI pattern Hyperintense on T1 weighted images Hypointense on T2 weighted images Loss of signal in chemical shift imaging (in phase out of phase) 1. Duffy P, Ryan J, Aldous W. Ultrasound demonstration of a 1.5 cm intrarenal angiomyolipoma. J Clin Ultrasound 1977; 5:111-113. 2. Lee TG, Henderson SC, Freeny PC, Raskin MM, Benson EP, Pearse HD. Ultrasound findings of renal angiomyolipoma. J Clin Ultrasound 1978; 6:150-155. 3. Shawker TH, Horvath KL, Dunnick NR, Javadpour N. Renal angiomyolipoma: diagnosis by combined ultrasound and computerized tomography. J Urol 1979; 121:675-676. Department of Diagnostic and Interventional Radiology 4. Bagley D, Appell R, Pingoud E, McGuire EJ. Renal angiomyolipoma: diagnosis and management. Urology 1980; 15:1-5.
Typical angiomyolipoma Department of Diagnostic and Interventional Radiology
Typical angiomyolipoma? Papillary carcinoma! Department of Diagnostic and Interventional Radiology
Angiomyolipoma?
Angiomyolipoma?
Density measurement Department of Diagnostic and Interventional Radiology Angiomyolipoma!
Angiomyolipoma?
Angiomyolipoma?
Angiomyolipoma?
Densitity measurement Department of Diagnostic and Interventional Radiology Angiomyolipoma!
Angiomyolipoma?
Angiomyolipoma?
MRI T2 T1 fat saturated Department of Diagnostic and Interventional Radiology
Chemical shift imaging In phase Out of phase Department of Diagnostic and Interventional Radiology Angiomyolipoma!
Angiomyolipoma?
Enhanced CT
MRI haste T2 fat sat In phase Department of Diagnostic and Interventional Radiology Out of phase
Contrast enhanced MRI Complicated cyst Department of Diagnostic and Interventional Radiology
Angiomyolipoma?
Angiomyolipoma?
CT
MRI Department of Diagnostic and Interventional Radiology Scar
Angiomyolipoma?
Angiomyolipoma?
CT No fat density Department of Diagnostic and Interventional Radiology
What to do?
US guided biopsy
Epithelioid cells Adipocyts Department of Diagnostic and Interventional Radiology Courtesy from Dr Letovanek
Adipocyts Courtesy from Dr Letovanek Department of Diagnostic and Interventional Radiology Epithelioids cells
Percutaneous biopsy He has performed percutaneous biopsy of renal masses Department of Diagnostic and Interventional Radiology
Percutaneous biopsy Sensitivity for diagnosis of malignancy 80-92% Specificity 83-100% Seeding of the needle track is possible Extremely rare (estimated( at less than 0.01%) Six cases described Major complications rare Hematuria may occur Self-limited limited bleeding frequent 1. Brierly RD, Thomas PJ, Harrison NW, Fletcher MS, Nawrocki JD, Ashton-Key M. Evaluation of fine-needle aspiration cytology for renal masses. BJU Int 2000; 85:14-18. 2. Caoili EM, Bude RO, Higgins EJ, Hoff DL, Nghiem HV. Evaluation of sonographically guided percutaneous core biopsy of renal masses. AJR Am J Roentgenol 2002; 179:373-378. 3. Lechevallier E, Andre M, Barriol D, et al. Fine-needle percutaneous biopsy of renal masses with helical CT guidance. Radiology 2000; 216:506-510. 4. Silverman SG, Gan YU, Mortele KJ, Tuncali K, Cibas ES. Renal masses in the adult patient: the role of percutaneous biopsy. Radiology 2006; 240:6-22. Department of Diagnostic and Interventional Radiology
Hyperechoic mass
No characterization
US guided biopsy
Renal cell carcinoma Department of Diagnostic and Interventional Radiology
Angiomyolipoma?
Angiomyolipoma?
Enhanced CT
US guided biopsy Department of Diagnostic and Interventional Radiology Renal cell carcinoma
Percutaneous biopsy Established indications Patients with a renal mass and known extrarenal primary malignancy Patients with a renal mass and imaging findings that suggest unresectable renal cancer Patients with a renal mass and surgical comorbidity Patients with a renal mass that have been caused by an infection Emerging indications Patients with a small (< 3 cm) hyperattenuating, homogeneously enhancing renal mass Patients with a renal mass considered for percutaneous ablation 1. Brierly RD, Thomas PJ, Harrison NW, Fletcher MS, Nawrocki JD, Ashton-Key M. Evaluation of fine-needle aspiration cytology for renal masses. BJU Int 2000; 85:14-18. 2. Caoili EM, Bude RO, Higgins EJ, Hoff DL, Nghiem HV. Evaluation of sonographically guided percutaneous core biopsy of renal masses. AJR Am J Roentgenol 2002; 179:373-378. 3. Lechevallier E, Andre M, Barriol D, et al. Fine-needle percutaneous biopsy of renal masses with helical CT guidance. Radiology 2000; 216:506-510. 4. Silverman SG, Gan YU, Mortele KJ, Tuncali K, Cibas ES. Renal masses in the adult patient: the role of percutaneous biopsy. Radiology 2006; 240:6-22. Department of Diagnostic and Interventional Radiology
Percutaneous radiofrequency ablation Thermal ablation technique Temperature in excess of 48-50 C Coagulation necrosis and cellular death Indications If radical nephrectomy would render the patient anephric Presence of significant comorbidities Tumor size strong predictor of outcome (< 4cm) Exophytic tumors Complications Lower as compared to partial or radical nephrectomy (0-11%) 1. Boss A, Clasen S, Kuczyk M, Schick F, Pereira PL. Image-guided radiofrequency ablation of renal cell carcinoma. Eur Radiol 2007; 17:725-733. 2. Silverman SG, Gan YU, Mortele KJ, Tuncali K, Cibas ES. Renal masses in the adult patient: the role of percutaneous biopsy. Radiology 2006; 240:6-22. 3. Zagoria RJ, Traver MA, Werle DM, Perini M, Hayasaka S, Clark PE. Oncologic efficacy of CT-guided percutaneous radiofrequency ablation of renal cell carcinomas. AJR Am J Roentgenol 2007; 189:429-436. Department of Diagnostic and Interventional Radiology
Radiofrequency ablation Department of Diagnostic and Interventional Radiology
Immediate post-treatment treatment control Department of Diagnostic and Interventional Radiology
3 months post-treatment treatment Department of Diagnostic and Interventional Radiology
Small solid mass
Non enhanced CT
Contrast enhanced CT Arterial phase Venous phase Department of Diagnostic and Interventional Radiology
MRI Haste Department of Diagnostic and Interventional Radiology Axial T2
MRI in / out of phase Department of Diagnostic and Interventional Radiology
Fat poor angiomyolipoma Department of Diagnostic and Interventional Radiology 1. Milner J, McNeil B, Alioto J, et al. Fat poor renal angiomyolipoma: patient, computerized tomography and histological findings. J Urol 2006; 176:905-909.
Conclusion Many hyperechoic solid renal masses are AML but Some hyperechoic solid renal masses are RCC These masses need further characterization CT MRI When CT or MRI fail to characterize the lesion Percutaneous biopsy Department of Diagnostic and Interventional Radiology