The effect of sampling more cores on the predictive accuracy of pathological grade and tumour distribution in the prostate biopsy

Abstract

The technique for taking prostatic biopsies has received a major evaluation from many departments around the world in terms of the number of cores, site of biopsy, complications, need for local anaesthesia or sedation, etc., and the authors from Charlottesville review their technique. They present data confirming the impression that increasing the number of cores increases diagnostic sensitivity. Authors from Chapel Hill have performed a pilot study into the concept that cyclooxygenase (COX)‐2 inhibitors inhibit tumour growth in prostate cancer, both in vivo and in vitro. In a few patients they found evidence to suggest that COX‐2 inhibitors may be of value in patients with prostate cancer, concluding that a large trial is indicated. Vascular endothelial growth factor (VEGF) is known to be an important angiogenic factor. The authors from Sweden assessed its value as a marker in renal cancer cells. They found it to be present in most such cells, and found that the correlation between VEGF expression and tumour stage and prognosis was valuable in terms of progression of renal cancer. OBJECTIVE To determine if increasing the number of cores at biopsy improves the predictive accuracy of the Gleason score or aids in anticipating the location and volume of prostate tumour. PATIENTS AND METHODS The charts of 75 consecutive patients who underwent radical retropubic prostatectomy for clinical T1–2 adenocarcinoma of the prostate were reviewed retrospectively; 31 patients had a sextant biopsy (group 1) and 44 had ≥ 8 cores taken (group 2). The concordance between biopsy data and final prostatectomy Gleason score, tumour location and volume was determined for each group. RESULTS There were no differences in mean age, prostate‐specific antigen level before biopsy or biopsy Gleason score for the two groups; 58% of group 1 had their final pathological grade changed after prostatectomy, vs 29% of group 2 (P < 0.05). In neither group was there a significant correlation between the percentage of cores positive for tumour and the percentage volume of prostate involved with cancer, or the ability of the biopsy to predict tumour location. CONCLUSION Taking ≥ 8 biopsy cores improved the pathological grading accuracy, which may be valuable in choosing a treatment for the patient with newly diagnosed prostate cancer.

Characteristics of insignificant clinical T1c prostate tumors

“…It has been demonstrated that the probability of detecting prostate carcinoma and the accuracy of pathologic grading both increase with increasing number of biopsy cores obtained. 12,13 The number of cores found to be positive for malignancy also varies according to the number of cores obtained, as does the probability of detecting an elevated level of involvement in a given positive core. When the Epstein criteria were developed, the standard technique in use at The Johns Hopkins Hospital was a sextant (i.e., six-core) biopsy procedure.…”

Trends in distribution and prognostic significance of Gleason grades on radical retropubic prostatectomy specimens between 1989 and 2001

“…[5][6][7][8][9][12][13][14] Technical aspects of needle biopsy that may have an impact on Gleason grading, including the use of ultrasound for guidance, the size of needle used, and the number of cores obtained, all have changed over time. 19 Similarly, the diminishing rates of transurethral resection may contribute to changes in the spectrum of prostate cancers that are diagnosed. 20 Nonetheless, clear trends can be discerned from previous studies regarding the distribution of GS on RRP specimens.…”

Minireview: Epigenetic Alterations in Human Prostate Cancers

“…The major unmet need is the lack of definitive prostate imaging that can discriminate likely carcinoma from focal inflammation, atrophy, scarring, etc. Because the biopsies are not directed at suspicious lesions, arguments continue to rage over the pattern of sampling, the zonal regions of the prostate to be sampled, the number of core samples to be taken, and when or whether repeat biopsy procedures should be pursued if prostate cancer is not detected (62,63). Of interest, serum testing for bound vs. free serum PSA was approved as a tool for reducing unnecessary prostate biopsies in men with an elevated serum PSA (64).…”