Value of Abdominal Ultrasound Scan, CT and MRI for Diagnosing Inferior Vena Cava Tumour Thrombus in Renal Cell Carcinoma

Background: We used abdominal ultrasound scan (USS), computed tomography (CT) and magnetic resonance imaging (MRI) findings in venous spread of renal cell carcinoma (RCC) to determine the superior extent of inferior vena cava (IVC) thrombus and IVC wall invasion and compared them with surgical and pathological reports.

Methods: From January 1999 to August 2007, 25 patients were diagnosed with RCC with IVC tumour thrombus. Before their operation, all patients had USS, contrast enhanced CT and MRI to find the superior extent of tumour thrombus and IVC wall invasion. All postprocessing techniques were performed by experienced radiologists. Two pathologists reported on all pathology specimens. The superior extent of tumour thrombus was confirmed by the senior surgeon at each operation, using the levels of thrombus defined according to 2004 Mayo Clinic classification. The radiographic results were compared with surgical and pathological findings.

Results: All patients had radical nephrectomy and tumour thrombus excision. Eight patients had RCC on the left side and 17 on the right side. According to the clinical and pathological findings, 6 patients had level I tumour thrombus, 9 level II, 5 level III and 5 level IV. Six patients had IVC wall invasion. No patient had evidence of lymph node or distant metastases. Of the 25 patients, USS correctly diagnosed the superior extent of tumour thrombus in 18/25, CT 23/25 and MRI 23/25. USS found 1 case of IVC wall invasion preoperatively.

Conclusions: Multidetector computed tomography and magnetic resonance imaging are comparable and more effective than abdominal ultrasound in diagnosing inferior vena cava tumour thrombus in renal cell carcinoma. None of the three methods can detect inferior vena cava wall invasion.