Is transition zone biopsy valuable in benign prostatic hyperplasia patients with serum prostate-specific antigen >10 ng/ml and prior negative peripheral zone biopsy?

Differences in Upgrading of Prostate Cancer in Prostatectomies between Community and Academic Practices

Objective. To determine whether initial biopsy performed by community or academic urologists affected rates of Gleason upgrading at a tertiary referral center. Gleason upgrading from biopsy to radical prostatectomy (RP) is an important event as treatment decisions are made based on the biopsy score. Materials and Methods. We identified men undergoing RP for Gleason 3 + 3 or 3 + 4 disease at a tertiary care academic center. Biopsy performed in the community was centrally reviewed at the academic center. Multivariate logistic regression was used to determine factors associated with Gleason upgrading. Results. We reviewed 1,348 men. There was no difference in upgrading whether the biopsy was performed at academic or community sites (OR 0.9, 95% CI 0.7-1.2). Increased risk of upgrading was seen in those with >1 positive core, older men, and those with higher PSAs. Secondary pattern 4 and larger prostate size were associated with a reduction in risk of upgrading. Compared to the smallest quartile of prostate size (<35 g), those in the highest quartile (>56 g) had a 49% reduction in risk of upgrading (OR 0.51, 95% CI 0.3-0.7). Conclusion. There was no difference in upgrading between where the biopsy was performed and community and academic urologists.

Low incidence of prostate cancer identified in the transition and anterior zones with transperineal biopsy

PURPOSE

Determine the incidence of anterior (AZ) and transition (TZ) zone prostate cancers using a transperineal mapping approach.

METHODS

A retrospective review of 137 patients with history of previous negative biopsy undergoing transperineal saturation biopsy for an elevated prostate-specific antigen (PSA), high-grade prostate intraepithelial neoplasia, atypical small acinar proliferation history, or abnormal digital rectal exam. The number of biopsy cores was determined by prostate volume and obtained using a predefined template. The electronic medical records were reviewed for patients' clinical and pathological characteristics.

RESULTS

Forty-one of 137 patients (31.4%) had positive biopsy for prostate adenocarcinoma; 11 were from 24-core, 19 from 36-core, and 11 from 48-core sampling. Glands > 45 mL had a mean of 1.7 previous biopsies and a PSA of 9.1 ng/mL. Glands < 30 mL were 1.3 and 6.3 ng/mL and glands 30-45 mL were 1.4 and 6.5 ng/mL. Glands < 45 mL had a higher number of positive biopsies per total cores. Seven patients chose active surveillance while 34 chose treatment. Of the 36- and 48-cores biopsies, 2.2% and 1.5%, respectively, were positive in the TZ. One patient was AZ-positive, 1 was TZ-positive, and 18 were peripheral zone (PZ)-positive alone. Twelve patients had cancer detected in PZ and TZ. Two patients developed urinary retention and one had a urine infection.

CONCLUSION

Transperineal saturation biopsy is a safe and efficacious method of prostate cancer detection in patients with previous negative biopsy and high suspicion for cancer. Few cancers were found to originate in the TZ or AZ alone. We recommend that initial biopsy templates should sample PZ with less focus on the TZ.

Diagnosis of prostate cancer

The contemporary challenge of prostate cancer diagnosis has been changed in the past decade from the endeavor to increase detection to that of detecting only those tumors that are clinically significant. Better interpretation of the role of prostate-specific antigen (PSA) and its kinetics as a diagnostic tool, the adoption of extended prostate biopsy schemes, and perhaps implementation of new transrectal ultrasound (TRUS) technologies promote the achievement of this clinical mission. This chapter reviews these issues as well as the change in practice of patient preparation for TRUS-biopsy and analgesia during it, the role of repeat and saturation prostate biopsies, and the interpretation of an incidental prostate cancer finding. Currently, the lifetime risk of a diagnosis of prostate cancer for North American men is 16%, compared to the lifetime risk of death from prostate cancer, which is 3% (Carter 2004). The advent of prostate-specific antigen (PSA) screening and transrectal ultrasonography (TRUS) has significantly impacted the detection of prostate cancer over the last 20 years. The mean age at diagnosis has decreased (Hankey et al. 1999; Stamey et al. 2004) and the most common stage at diagnosis is now localized disease (Newcomer et al. 1997; Stamey et al. 2004). The goal of prostate cancer screening is to detect only those men at risk for death from the disease at an early curable phase. The ambiguous natural history of this most common malignancy in men, being latent with questionable life-threatening potential in a large number of cases on the one hand, with only a relatively small number (though not negligible) of highly malignant cases on the other, propels many doubts about whether this is possible. This was famously phrased more than 20 years ago by Whitmore who asked: "Is cure possible for those in whom it is necessary; and is it necessary for those in whom it is possible?" This is probably even more relevant nowadays. During the past decade two factors influenced significantly the increased detection rate of prostate cancer in general and that of clinically insignificant prostate cancers in particular: the widespread use of serum PSA as a screening tool to a large extent and to a lesser though significant extent the application of extended multiple core biopsy schemes (Master et al. 2005). In fact, 75% of men in the United States aged 50 years and older have been screened with the PSA test (Sirovich et al. 2003). Outside of the screening context, which is dealt with in depth in Chap. 5, clinical suspicion of prostate cancer is raised usually by abnormal digital rectal examination (DRE) and/or by abnormal levels of serum PSA. Final diagnosis is achieved only based on positive prostate biopsies.