The accuracy of renal tumor biopsy: analysis from a national prospective study.

OBJECTIVE: To assess preoperative renal tumor biopsy (RTB) accuracy. MATERIALS AND METHODS: As part of the prospective NEPHRON study, data from 1,237 renal tumors were collected, including the use and results of RTB and final histology following nephrectomy. During the 6 months period of inclusion, 130 preoperative biopsies were performed. We used the kappa coefficient of the McNemar test to determine the concordance between the biopsy and the nephrectomy specimen (NS) regarding four parameters: malignant/benign status, histological subtype, Fuhrman grade and microscopic necrosis. RESULTS: Preoperative biopsies were performed in 9.7 and 11.4 % of the 667 radical and 570 partial nephrectomies, respectively. Tumor biopsy was inconclusive in 7.7 % of the cases. In 117 cases, a comparison between RTB and NS was available. Benign tumors accounted for three (2.6 %) and five (4.3 %) of the RTB and NS, respectively (κ = 0.769, good). With seven (6 %) discordant results in terms of histological subtype characterization between RTB and final pathology, RTB accuracy was considered excellent (κ = 0.882). In 33 cases (31.7 %), Fuhrman grade was underestimated at biopsy resulting in an intermediate concordance level (κ = 0.498). Tumor microscopic necrosis was identified in 12 RTB (10.4 %) versus 33 NS (28.4 %) (κ = 0.357, poor). CONCLUSIONS: RTB provides good to excellent diagnostic performance for discriminating malignancy and tumor histological subtype. However, its performance is intermediate or even poor when considering prognostic criteria like Fuhrman grade or microscopic necrosis. Thus, this possible inaccuracy should be taken into consideration when using RTB for accurate guidance of treatment strategy.

[Cancer of the prostate. 1. Epidemiology]. / Cancer de prostate. 1. Epidémiologie.

Prostatic cancer is the second most frequent cancer in men in France. It is a serious disease with a relative 5-year survival of 42%. Although the incidence of latent forms appears to be constant throughout the world, the incidence of clinical forms varies from country to country and according to race. These aspects are in favour of a dual mechanism of prostatic carcinogenesis: initiation of a cellular modification, which may be transmitted genetically according to an autosomal dominant mode, but whose expression may be influenced by the environment, and successive steps of transformation (epigenetic factors) which are essentially environment-dependent. The main identified risk factors essentially consist of a direct family history, age and a diet rich in animal fats. In contrast, neither the presence of benign prostatic hypertrophy, nor the characteristics of the sex life or a history of vasectomy appear to influence the incidence of prostatic cancer. The main epidemiological data currently available are presented.

[Cancer of the prostate. 2. Physiology and cellular development]. / Cancer de prostate. 2. Physiologie et développement cellulaire.

Prostatic cancer is the second most frequent cancer in men in industrialised countries. The histological analysis of its initial development demonstrates the existence of precancerous lesions, PIN. The initial presence of several different cell populations accounts for the development of contingents of hormone-sensitive and hormone-resistant cells. The presence of numerous neuroendocrine cells appears to be a factor of poor prognosis. Hormones are intimately involved in the development of prostatic cancer and are an integral part of its treatment. Progress in molecular biology has furthered out knowledge of this disease. In particular, growth factors such as EGF and FGF are particularly involved and are starting to have a clinical application. The oncogene and anti-oncogene system is currently being explored (particularly p53 abd BCL 2). They are the basis for carcinogenesis and analysis of these factors will allow a better approach to the mechanisms of tumour induction and development.

[Renal nephrogenic nephroma: an little known exceptional tumor. Apropos of a case disclosed by xanthogranulomatous pyelonephritis]. / Le néphrome néphronogène rénal: une tumeur exceptionnelle peu connue. A propos d'un cas révélé par une pyélonéphrite xantho-granulomateuse.

The authors report a new case of an exceptional benign renal tumour: nephronogenic nephroma, composed of differentiation of the blastema into primitive nephronic formations. It raises the problem of differential diagnosis with adult Wilms' tumour and renal blastematosis. In this patient, it was associated with segmental xanthogranulomatous pyelonephritis, presenting in the form of psoïtis and an abscess of the thigh. Total nephrectomy was performed.