Comparison of type I and II papillary renal cell carcinoma (RCC) and clear cell RCC.

OBJECTIVE: To compare the pathological features of clear cell renal cell carcinoma (ccRCC) with papillary RCC (pRCC) and further differentiate type I and II pRCC as independent prognosticators for survival. PATIENTS AND METHODS: From September 1994 to February 2007 557 RCCs were treated and reviewed. All patients underwent radical nephrectomy or nephron-sparing surgery. We reviewed patient data and correlated RCC subtypes to tumour size, pathological stage, nuclear grade, and 5-year cancer-specific survival (CSS). pRCC was re-evaluated in to type I and II. The 2002 Tumour-Node-Metastasis and Fuhrman classifications were used. RESULTS: In all, 391 (70%) patients had ccRCC, 96 (17%) had pRCC, 34 (6%) had chromophobe RCC, seven (1%) had ductus Bellini RCC and 29 (5%) had unclassified RCC. Upon re-evaluation 34 patients had type I pRCC and 62 had type II. The pRCCs were significantly smaller than the ccRCCs, at a mean (sd) of 4.5 (2.5) cm vs 5 (2.9) cm (P = 0.013), and multifocal (25% vs 12%, P = 0.001). Whereas patients with ccRCC had significantly more primary metastases (12% vs 3%, P = 0.014). The mean (sd) follow-up was 42.3 (41.4) months. The 5-year CSS for M0 patients was 84% for ccRCC and 90% for pRCC (P = 0.573). At multivariate analyses predictors for 5-year CSS were only tumour size (hazard ratio, HR 2.6, P < 0.001), pathological stage (HR 3.9, P < 0.001) and nuclear grade (HR 2.7, P < 0.001). The type I and II pRCCs had significantly different lymphovascular invasion (LVI) and 5-year CSS rates (94% vs 74%, P = 0.03). CONCLUSIONS: The ccRCCs were significantly larger at diagnosis than the pRCCs. The histological subtype (pRCC vs ccRCC) had no impact on the 5-year CSS in multivariate analyses. The type I and II pRCCs had similar histopathological features except for a significant difference in LVI. However, the 5-year CSS was significantly different in type I and II pRCC.

Diagnostic accuracy of computed tomography-guided percutaneous biopsy of renal masses.

OBJECTIVE: Modern imaging modalities increase the detection of small (

Renal tumour size measured radiologically before surgery is an unreliable variable for predicting histopathological features: benign tumours are not necessarily small.

OBJECTIVE: To compare histopathological findings as a function of radiological tumour size, as published data suggest that small renal tumours are often benign and large tumours are renal cell cancer (RCC). PATIENTS AND METHODS: Data from 543 surgically treated patients with solid renal tumours were analysed retrospectively. Tumour size measured by computed tomography (CT) before surgery was stratified into seven subgroups (cm): 0-2, 2.1-3, 3.1-4, 4.1-5, 5.1-6, 6.1-7 and >7, and correlated with final histology. RESULTS: In all, 80 lesions (14.7%) were benign on final histology; tumour size did not correlate with benign histology (P=0.660). Histopathological tumour size was not statistically significant different (P=0.521) from measured tumour size on CT, and there was no statistical significance between CT and histopathological tumour size (P=0.528). Only 13 (17%) of lesions were correctly defined as benign on CT before surgery, whereas 67 (83%) were considered to be suspicious for malignant disease. Only one patient with a tumour correctly defined as benign had a radical nephrectomy; by contrast, 28 of 67 (42%) had a radical nephrectomy for benign lesions not correctly identified as benign on CT before surgery (P<0.001). CONCLUSION: Substantially many renal masses are benign, independent of tumour size. Radical nephrectomy could potentially have been avoided in 42% of patients with benign renal tumours. These data provide a good argument for the use of a more refined preoperative diagnostic evaluation, in particular needle biopsy.