[Prostatic rebiopsy. Prognosis factors of the anatomopathologic result]

Significación pronóstica del PIN y la atípia glandular focal en la Biopsia Transrectal Ecodirigida de Próstata

OBJECTIVE

To review the incidence of PIN and Atypical Small Acinar Proliferation (ASAP) on first biopsy, the risk to find cancer on following biopsies and what is the importance given to this findings, analizing how frequently and how long after the initial finding this patients are rebiopsied.

METHOD

We selected 6000 patients who underwent TRUS biopsy between 1994 and 2002. Patients with prior cancer diagnosis were not included. 861 of them underwent more than one biopsy, adding up to a total of 7127 biopsies. A descriptive study has been done including percentages and percentiles for qualitative variables, mean and median for continuous variables.

RESULTS

Incidence of cancer on the first biopsy was 39,1%. PIN and ASAP are stable or slightly increase from 2 and 2,1% respectively on the first biopsy to more than 6% on the fourth and fifth ones. Mean time between biopsies when ASAP or PIN are the initial findings is 180 +/- 221,6 and 264 +/- 213,8 days respectively. Just 42 and 40% of patients with prior PIN or ASAP diagnose are rebiopsied. On subsequent biopsies 45 and 40% of cancers were respectively found.

CONCLUSIONS

Presence of PIN or ASAP implies a higher cancer risk on subsequent biopsies; in spite of that, less than half of them are biopsied again. Performing two more biopsies or an amplified biopsy can find most of the tumors associated.

Diagnóstico del cáncer de próstata mediante biopsia ampliada de 24 cilindros

OBJECTIVE

To determine the diagnostic performance of extended prostatic biopsy (PB) in prostate cancer (PC) and variables affecting positivity.

MATERIALS AND METHODS

Patients (n = 147) underwent 24 cylinder PB at the Arquitecto Marcide Hospital, Ferrol, La Coruña, between December 2002-September 2004. Inclusion criteria were the following: patients aged < or = 70 with one or more negative PB or aged < or = 75 with two or more negative PB. An univariate analysis was carried out using the chi-squared test for the qualitative variables and the t-Student and U Mann-Whitney tests in the case of the quantitative variables, plus a logistical regression analysis in order to identify those variables related to the extended PB positivity.

RESULTS

60 patients (40.82%) were identified as having PC. Significant differences were observed in prostatic volume, free/total PSA ratio in the initial PB, free/total PSA ratio in the extended PB, PSA-density in the extended PB as well as the existence of chronic prostatitis in previous PB. During the multivariate analysis it was found that the PSA-density and the presence of chronic prostatitis in previous PB independently predicted the positivity of the extended PB.

CONCLUSIONS

Extended PB allows for the detection of PC in 40.82% of patients with previous negative PB. The increase in PSA density is associated with a greater probability of PC, whilst the existence of chronic prostatitis in prior PB significantly reduces the probability of PC in the extended PB.