Population-based patterns of radical retropubic prostatectomy use

OBJECTIVES

To examine the use of radical retropubic prostatectomy (RRP) in a large population-based study.

METHODS

Identification of all RRPs performed in the province of Quebec between the years 1988 and 1993 was accomplished by relying on the Quebec Healthcare Plan Database.

RESULTS

Overall, 2861 RRPs have been performed during the study period. On average, 80% of surgeries have been performed by urologists using this surgery 12 times or less annually. Of all surgeries, 420 (15%) RRPs have been performed in individuals 71 years of age or older.

CONCLUSIONS

Each year, most RRPs (80%) in this population-based study were performed by urologists performing this procedure 12 times or less annually. A substantial proportion (15%) of RRPs have been performed in men 71 years of age or older, in whom the detriments of radical surgery may outweigh its benefits. These findings could potentially contribute to suboptimal outcomes when radical prostatectomy is compared with alternative treatment modalities.

Computer-assisted comparative analysis of four-sector and six-sector biopsies of the prostate

OBJECTIVES

To assess the potential difference in positive biopsy rates between four-sector and six-sector biopsy methods.

METHODS

This computer-assisted analysis is based on the records of 156 consecutive patients previously diagnosed with T1c cancer on systematic sextant biopsy of the peripheral zone. For each patient the computer randomly deleted one biopsy result from the left and right prostatic lobes. The deletion process was repeated 1000 times. Based on four randomly chosen biopsy cores, we determined the number of undetected cancers initially diagnosed with sextant biopsy.

RESULTS

Based on four-sector biopsy cores of the peripheral zone, between 6 and 30 (3.8% to 19.2% of cases) nonpalpable, isoechoic prostate cancers that were detected with sextant biopsy would have remained undiagnosed.

CONCLUSIONS

Our results suggest that the number of biopsy cores used in the early detection of nonpalpable, isoechoic prostate cancer may substantially affect the rate of positive findings.

Role of prostate-specific antigen density after applying age-specific prostate-specific antigen reference ranges

OBJECTIVES

To determine the potential role of prostate-specific antigen (PSA) density (PSAD) in the early detection of prostate carcinoma if we apply age-specific PSA reference ranges (2.5 ng/mL or less for ages 40 to 49 years, 3.5 or less for ages 50 to 59, 4.5 or less for ages 60 to 69, and 6.5 or less for ages 70 to 79.

METHODS

We retrospectively reviewed 3234 cases referred to us by urologists for transrectal ultrasound (TRUS) between January 1, 1991, and September 28, 1993. We included 2429 patients in the study, ages 40 to 79 years, with Hybritech or Abbott IMx serum PSA determinations and without previously diagnosed prostate cancer. We performed digital rectal examination (DRE) and TRUS in all cases, and TRUS-guided biopsies when indicated. We used stringent criteria to define 736 cases without clinical evidence of malignancy that were designated as a "benign group."

RESULTS

In the benign group, we found serum PSA to increase with age in parallel with the increase in prostate volume with age (r = 0.25 and r = 0.26, respectively). The association between serum PSA and prostate volume was stronger (r = 0.46). Using multiple regression analysis, prostate volume accounted for 18% of the variation in serum PSA, whereas age accounted for only an additional 2%. PSAD, which directly relates serum PSA to prostate volume, showed a weak association with age (r = 0.1). In the entire study population of 2429 cases, 555 patients had negative DRE and TRUS results and a serum PSA level between the age-specific upper limit of normal and 10.0 ng/mL. According to the proposed age-specific algorithm, these patients would have required automatic biopsies. Of these, 315 cases (56.8%) still had a PSAD of less than 0.15. We performed biopsies in 108 of these 315 and detected only two cancers, for a positive biopsy rate (PBR) of 1.9%. The remaining 240 cases had a PSAD of 0.15 or higher, and we performed biopsies in 217 of these cases and detected 59 cancers, for a PBR of 27.2%.

CONCLUSIONS

The use of age-specific PSA reference ranges does not totally account for the effect of prostate volume on serum PSA. Therefore PSAD can still be used to reduce safely the number of biopsies performed in patients with negative DRE and TRUS results and a serum PSA level 10.0 ng/mL or less and above the age-specific upper limit of normal.

Prospective evaluation of prostate-specific antigen density and systematic biopsies for early detection of prostatic carcinoma

Significant controversies persist in regard to the need for systematic biopsies in patients with serum prostate-specific antigen (PSA) levels above 4 ng/mL (Hybritech assay), especially if they show no signs of prostatic cancer on digital rectal examination (DRE) or transrectal ultrasonography (TRUS). We evaluated 565 consecutive patients referred to us for prostatism, suspicious lesions on DRE, or an elevated serum PSA level. These patients do not represent a purely screened population. A detection rate of 38.4 percent was achieved by performing directed biopsies of suspicious lesions on DRE and/or TRUS, and systematic biopsies of all patients with serum PSA levels above 4 ng/mL. Among 142 patients with serum PSA between 4.1 and 10 ng/mL, but without suspicion for cancer on DRE and TRUS (DRE- TRUS-), a large number of patients (6.2) were subjected to systematic biopsies to detect one cancer. A receiver-operating characteristics curve for PSA density (PSAD) applied to this population confirmed that the best cut-off point for biopsies was a PSAD of 0.15, below which only two of twenty-three cancers would have been missed, sparing biopsies in 77 of 142 patients. A similar approach was applied to DRE- TRUS- patients with serum PSA levels above 10 ng/mL. The number of cancers in those with serum PSA between 10.1 and 14 ng/mL was too low to establish a PSAD cut-off point. In patients with serum PSA above 14 ng/mL, the best PSAD cut-off point for biopsies was 0.3, below which two of thirteen cancers would have been missed, sparing biopsies in 19 of 39 patients. We conclude that PSAD can safely reduce the number of patients subjected to systematic biopsies without significantly compromising cancer detection.

Management of ureteral stones by extracorporeal shock wave lithotripsy using Lithostar lithotriptor

In 282 patients 290 ureteral stones were treated with extracorporeal shock wave lithotripsy using the Lithostar lithotriptor. Stones were in the upper ureter in 198 units (68.3%), middle ureter in 36 (12.4%) and lower ureter in 56 (19.3%). The average stone mass was 11.9 mm. and the mean number of shock waves was 4,913 for all levels with a mean kv. of 16.9. The average number of sessions was 1.5 for all sites. Auxiliary measures in the form of ureteral catheterization were done in 24 patients (8.5%) and internal stenting in 12 (4.25%), all of whom had upper or middle ureteral stones. Disintegration of the stones was achieved in 99% of the upper, 93.7% of the middle and 91.7% of the lower ureteral stones. However, clearance of fragments within 3 months from the last session was achieved in 94.8% of the upper, 87.5% of the middle and 91.7% of the lower ureteral stones for an overall stone-free rate of 93.3%.