Discussion of Last Issue's Case Scenario

Case Scenario

Case Scenario Discussion of Last Issue’s Case Scenario IN THE LAST ISSUE, DR. LEPOR 53-year-old man with a prostate-specific antigen (PSA) level of 4.2 ng/dL has a benign 40 g prostate on digital rectal examination. The patient undergoes a 12-core biopsy of the prostate, which shows a single focus of prostatic intraepithelial neoplasia (Figure 1). A THE PRESENTED THIS CASE REPORT: Figure 1. High-grade prostatic intraepithelial neoplasia: micropapillary pattern (hematoxylin and eosin,
400). FOLLOWING MANAGEMENT OPTIONS WERE OFFERED: 1. Immediate repeat 12-core biopsy 2. Immediate repeat saturation biopsy 3. Immediate repeat biopsy of transition zone 4. Repeat biopsy in 1 year 5. Repeat biopsy in 3 years independent of PSA change VOL. 7 NO. 3 2005 REVIEWS IN UROLOGY 185 Case Scenario continued AUTHOR’S DISCUSSION High-grade prostatic intraepithelial neoplasia (HGPIN) was described by Brawer and associates in 1991.1 Because HGPIN was often observed in proximity to prostate cancer, it was assumed to represent a premalignant condition.2 Transrectal ultrasound–guided biopsy became widely accepted for the diagnosis of prostate cancer in the early 1990s. Hodge and colleagues3 recommended performing sextant biopsies directed bilaterally to the apex, middle, and base of the prostate in the midsagittal plane. The number and orientation of these biopsies were established empirically. For cases in which HGPIN was detected on transrectal ultrasound–guided sextant biopsy, rebiopsy yielded a diagnosis of prostate cancer in 27% to 100% of cases.4 Therefore, repeat biopsy was deemed mandatory if HGPIN was observed in a 6-core sextant biopsy. Several investigators have recommended that a 12-core biopsy be routinely performed in order to provide adequate tissue sampling to exclude prostate cancer.5 In the modern era, a 6-core biopsy is considered inadequate. The number of tissue cores required to exclude coexisting prostate cancer in the presence of HGPIN remains controversial. Taneja and associates4 of New York University (NYU) Medical Center repeated a 12-core biopsy in men who were found to have HGPIN without co-existing prostate cancer, and only 2% of men were found to have prostate cancer. This implies that a 12-core biopsy is adequate to exclude co-existing prostate cancer in men with HGPIN. Other investigators have reported a higher rate of prostate cancer detection following an initial 12-core biopsy.6 On the basis of our data, we would not recommend repeat biopsy. Biopsy of the transition zone rarely yields prostate cancer when it is performed at the time of initial biopsy. There is no consensus regarding the indication for transition zone biopsy. We generally perform transition zone biopsy in cases where the PSA progressively rises despite multiple negative peripheral zone biopsies. 186 VOL. 7 NO. 3 2005 REVIEWS IN UROLOGY We have shown that men with HGPIN are at higher risk for developing prostate cancer independent of changes in PSA level.7 Repeat 12-core biopsies were performed on men 3 years after the initial diagnosis of HGPIN. Twentyfive percent of these men were found to have prostate cancer.7 Three of these men underwent radical retropubic prostatectomy and all had pT2 disease. The changes in PSA level were similar in men with or without prostate cancer on the repeat biopsy, indicating that rebiopsy should be performed in all men independent of PSA change. We do not know if the HGPIN developed into prostate cancer or a coexisting cancer grew to a detectable level; whatever the case, the cancer detection rate of 25% argues in favor of repeating the biopsy. The optimal timing for repeat biopsy in the presence of HGPIN is unknown. We believe it is unlikely that men with HGPIN will develop local or systemic metastases in a 3-year interval. Therefore, at NYU Medical Center, we would manage this patient with repeat biopsy in 3 years independent of PSA change. References 1. 2. 3. 4. 5. 6. 7. Brawer MK, Bigler SA, Sohlberg OE, et al. Significance of prostatic intraepithelial neoplasia on prostate needle biopsy. Urology. 1991;38:103-107. Bostwick DG. Prostatic intraepithelial neoplasia is a risk factor for cancer. Semin Urol Oncol. 1999;17:187-198. Hodge KK, McNeal JE, Stamey TA. Ultrasound guided transrectal core biopsies of the palpably abnormal prostate. J Urol. 1989;142:66-70. Lefkowitz GK, Sidhu GS, Torre P, et al. Is repeat prostate biopsy for high-grade prostatic intraepithelial neoplasia necessary after routine 12-core sampling? Urology. 2001;58:999-1003. Levine MA, Ittmann M, Melamed J, Lepor H. Two consecutive sets of transrectal ultrasound guided sextant biopsies of the prostate for the diagnosis of prostate cancer. J Urol. 1998;159:471-475; discussion 475-476. Rosser CJ, Broberg J, Case D, et al. Detection of high-grade prostatic intraepithelial neoplasia with the five-region biopsy technique. Urology. 1999;54:853-856. Lefkowitz GK, Taneja SS, Brown J, et al. Followup interval prostate biopsy 3 years after diagnosis of high grade prostatic intraepithelial neoplasia is associated with high likelihood of prostate cancer, independent of change in prostate specific antigen levels. J Urol. 2002;168:1415-1418.