Imaging characteristics of papillary renal cell carcinoma by computed tomography scan and magnetic resonance imaging.

AIM: To analyse the differences in the patterns between clear and papillary renal cell carcinomas using magnetic resonance imaging (MRI) and dual-phase helical computed tomography (CT). METHODS: We examined seven patients with papillary renal cell carcinoma, and six with clear cell carcinoma. The highest attenuation value of tumors in the corticomedullary phase (CMP) and the excretory phase (EP) was measured using the observer-defined region of interest (ROI). MRI consisted of T1-weighted and T2-weighted spin-echo imaging. RESULTS: All five tumors except for one with papillary renal cell carcinoma showed homogenous hypointensity, but all six tumors with clear cell carcinoma showed heterogeneous hyperintensity on their T2-weighted images. In the CMP, the mean CT numbers of the papillary renal cell carcinomas were significantly lower than those of the clear cell carcinomas. The mean enhancement of the papillary renal cell carcinomas in the CMP and the EP was significantly lower than that of the clear renal cell carcinomas. The mean CT numbers of the clear cell carcinomas in the CMP were markedly increased from those on the unenhanced CT; those in the EP were decreased gradually. But the mean CT numbers of the papillary renal cell carcinomas in the EP were still slightly more increased than those in the CMP. The enhancement patterns of the papillary renal cell carcinomas in the CMP and the EP were homogenous, but those of the clear cell carcinomas were heterogeneous. CONCLUSIONS: We can speculate the differential diagnosis from clear to papillary renal cell carcinoma using MRI and dual-phase helical CT.

[Two cases of femoral nerve palsy after radical prostatectomy].

We report two cases of femoral nerve palsy after radical prostatectomy due to compression ascribed to the use of a ring retractor. The first case is in a 69-year-old man who fell when getting out of bed on the first postoperative day. Physical examination revealed hypoesthesia around the patella and weakness of the quadriceps muscle. The second case is in a 66-year-old man who complained of numbness of the anteromedial aspects of the right thigh and inability to extend his right knee on the first postoperative day. Postoperative femoral nerve palsy is not a well-recognized complication in urology. The literature was reviewed and the management of postoperative femoral nerve palsy was discussed.

[Adrenocorticotropic hormone-secreting adrenal pheochromocytoma: a case report].

A 55-year-old woman with transient faintness was referred to our hospital. Laboratory studies showed high levels of plasma catecholamines, cortisol, adrenocorticotropic hormone (ACTH) and urinary vanyl mandelic acid (VMA). Abdominal computed tomography (CT) showed a right adrenal tumor measuring 4.5 cm diameter that was enhanced heterogeneously by contrast medium. Brain CT and chest CT did not detect any other tumors. Under the clinical diagnosis of ectopic ACTH secreting adrenal pheochromocytoma, we performed right adrenalectomy. Pathological findings showed pheochromocytoma, and tumor cells were heterogeneously stained by anti-ACTH antibody.

[Periureteral inflammatory pseudotumor: a case report].

A 59-year old female presented with right flank pain and hydronephrosis. Abdominal computed tomography (CT) and magnetic resonance imaging (MRI) before admission (August 2001), revealed a periureteral mass measuring 11 cm in length along the right ureter. Since the preoperative image examinations could not exclude a malignancy, she was admitted for surgery. After admission, however, she presented no abnormal findings in laboratory investigations including tumor markers, urinalysis, urine cytology and retrograde pyelography. C-reactive protein was normalized. CT after admission (September 2001), showed spontaneous regression of the mass. We cancelled the operation and decided to carefully watch this lesion by CT. The lesion continued to regress thereafter. Judging from the clinical course, we regard the mass as inflammatory pseudotumor although pathological diagnosis was not performed. The possibility of preserving the urinary tract in this disease is discussed by reviewing the previously reported inflammatory pseudotumor of the upper urinary tract.