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To evaluate the use of dual-phase three-dimensional magnetic resonance (MR) angiography in the preoperative staging of renal cancer.MR angiography was performed in 18 patients before performance of partial (n = 7), radical (n = 10), or laparoscopic (n = 1) nephrectomy to treat renal cancer. Dynamic, three-dimensional MR angiograms were obtained with gadoteridol enhancement, breath holding, and a three-dimensional spoiled gradient-echo sequence. Images were obtained at 15-second intervals to achieve opacification of arteries and veins. Source, maximum intensity projection, and multiplanar reconstruction images were evaluated. Imaging results were compared with surgical findings.Renal arterial phase MR angiograms depicted 30 of 31 (97%) surgically confirmed renal arteries, with one false-positive result (an artery that arose from an early-branching single main renal artery, interpreted as a separate accessory artery). Renal venous phase MR angiograms depicted all seven instances of renal vein involvement, including extension to the inferior vena cava in two patients. Collateral vessels around the tumor, including prominent gonadal veins in three patients, were demonstrated. Additional findings included adenopathy and adrenal and pulmonary metastases.Dual-phase MR angiography of the kidney may be a useful technique in depicting renal vessels before nephrectomy.

In the setting of von Hippel-Lindau disease, accurate quantitation of kidney lesions is important for genetic research. Unfortunately, fully automated quantitation is difficult because the lesion boundaries are complex. Therefore, we developed a method to semi-automate the quantitation of these renal lesions. We studied helical CT scans of 10 kidneys from 8 patients with von Hippel-Lindau disease. The kidneys were segmented from surrounding structures using an interactive marker-controlled watershed algorithm. Renal lesions (cysts and solid tumors) were identified using thresholding and then characterized by size using mathematical morphology and granulometry. There were 50 cysts and 16 solid lesions. The mean (/spl plusmn/ sd) numbers of interior and exterior manually placed contours required to perform a complete watershed segmentation of the kidneys were 2.2 /spl plusmn/1.2 and 1.2 /spl plusmn/0.6, respectively. The mean difference between the watershed and manual methods of computing renal volume was 13 /spl plusmn/18 mL (5 /spl plusmn/2% of total renal volume) and is not clinically significant. There was no significant difference between volumes of renal lesions measured manually and using the semi-automated method (p > 0.3).

Hereditary papillary renal carcinoma (HPRC) is a recently recognized form of inherited kidney cancer characterized by a predisposition to develop multiple, bilateral papillary renal tumours. The pattern of inheritance of HPRC is consistent with autosomal dominant transmission with reduced penetrance. HPRC is histologically and genetically distinct from two other causes of inherited renal carcinoma, von Hippel-Lindau disease (VHL) and the chromosome translocation (3;8). Malignant papillary renal carcinomas are characterized by trisomy of chromosomes 7, 16 and 17, and in men, by loss of the Y chromosome. Inherited and sporadic clear cell renal carcinomas are characterized by inactivation of both copies of the VHL gene by mutation, and/or by hypermethylation. We found that the HPRC gene was located at chromosome 7q31.1-34 in a 27-centimorgan (cM) interval between D7S496 and D7S1837. We identified missense mutations located in the tyrosine kinase domain of the MET gene in the germline of affected members of HPRC families and in a subset of sporadic papillary renal carcinomas. Three mutations in the MET gene are located in codons that are homologous to those in c-kit and RET, proto-oncogenes that are targets of naturally-occurring mutations. The results suggest that missense mutations located in the MET proto-oncogene lead to constitutive activation of the MET protein and papillary renal carcinomas.