[Correlation of the anatomo-pathological staging of radical prostatectomy specimens with the amount of cancer in the preoperative sextant biopsy].

OBJECTIVE

We assess the value of the percent of cancer in needle cores of sextant biopsy for predicting the risk of extraprostatic extension at radical retropublic prostatectomy.

MATERIAL AND METHODS

We reviewed prostate needle biopsy findings in 97 patients with prostate cancer T1c-T2, who subsequently underwent radical retropubic prostatectomy. In each needle biopsy were assessed, number of cores positive, percent of cores positive, percent cancer in all cores, Gleason score, intraepithelial neoplasia, perineural invasion and vascular invasion. Initial PSA and preoperative clinical stage were incorporated with biopsy results into a univariate and multivariate model to determine the parameters most predictive of pathological stage.

RESULTS

Of the 97 patients, 72 (74%) had organ confined cancer and 25 (26%) had extraprostatic extension. The average of cores positive for organ confined cancer was 4.2 (median 4) vs. 6.9 (median 6) for extraprostatic extension (p = 0.001), the percent of cores positive for organ confined cancer was 34.9% (median 28) vs. 53.8% (median 46) for extraprostatic extension (p = 0.013). The average of cancer in all cores in organ confined cancer was 13.6% (median 6) vs. 30.5% (median 30) for extraprostatic extension (p = 0.002). The mean Gleason score in needle cores was 5.9 (median 6) in organ confined cancer vs. 6.6 (median 7) in extraprostatic extension (p = 0.007). The average of intraepithelial neoplasia in needle cores was 3 (4%) in organ confined cancer vs. 1 (4%) in extraprostatic extension (p = 0.972). The perineural invasion of needle cores was 6 (8.3%) in confined cancer vs. 4 (16%) in extraprostatic extension (p = 0.355). Univariate analysis demonstrated that the risk of extraprostatic extension is predicted by the number of cores positive (p = 0.003), the percent of cores positive (p = 0.006), the percent of cancer in all cores (p = 0.001), the Gleason score (p = 0.002), the clinical stage (p = 0.019) and initial PSA (p = 0.032). Extraprostatic extension is not predicted by the intraepithelial neoplasia (p = 0.971), vascular invasion and perineural invasion (p = 0.285). Multivariate analysis showed that the percent of cancer in all cores is the strongest predictor of extraprostatic extension (p = 0.035). With a percent of cancer less than 3% in the biopsy specimen, the risk of extraprostatic extension is 11.5%.

CONCLUSIONS

The amount of cancer on preoperative needle sextant biopsy is the strongest predictor of prostate stage, but it is slightly practical at the moment of admitting or to reject a patient for radical prostatectomy.