High risk of under-grading and -staging in prostate cancer patients eligible for active surveillance - Abstract

BACKGROUND: Active surveillance (AS) is increasingly offered to patients with low risk prostate cancer.

The present study was conducted to evaluate the risk of tumor under-grading and -staging for AS eligibility. Moreover, we analyzed possible biomarkers for predicting more unfavorable final tumor histology.

METHODS: 197 patients who underwent radical prostatectomy (RPE) but would have met the EAU (European Association of Urology) criteria for AS (PSA< 10 ng/ml, biopsy GS ≤ 6, ≤ 2 cancer-positive biopsy cores with ≤ 50% of tumor in any core and clinical stage ≤ T2a) were included in the study. These AS inclusion parameters were correlated to the final histology of the RPE specimens. The impact of preoperative PSA level (low PSA ≤ 4 ng/ml vs. intermediate PSA of >4-10 ng/ml), PSA density (< 15 vs. ≥ 15 ng/ml) and the number of positive biopsy cores (1 vs. 2 positive cores) on predicting upgrading and final adverse histology of the RPE specimens was analyzed in uni- and multivariate analyses. Moreover, clinical courses of undergraded patients were assessed.

RESULTS: In our patient cohort 41.1% were found under-graded in the biopsy (final histology 40.1% GS7, 1% GS8). Preoperative PSA levels, PSA density or the number of positive cores were not predictive for worse final pathological findings including GS >6, extraprostatic extension and positive resection margin (R1) or correlated significantly with up-grading and/or extraprostatic extension in a multivariate model. Only R1 resections were predictable by combining intermediate PSA levels with two positive biopsy cores (p = 0.004). Sub-analyses showed that the number of biopsy cores (10 vs. 15 biopsy cores) had no influence on above mentioned results on predicting biopsy under-grading. Clinical courses of patients showed that 19.9% of patients had a biochemical relapse after RPE, among all of them were under-graded in the initial biopsy.

CONCLUSION: In summary, this study shows that a multitude of patients fulfilling the criteria for AS are under-diagnosed. The use of preoperative PSA levels, PSA density and the number of positive cores were not predictable for under-grading in the present patient collective.

Written by:
Heidegger I, Skradski V, Steiner E, Klocker H, Pichler R, Pircher A, Horninger W, Bektic J.   Are you the author?
Medical University of Innsbruck, Department of Urology, Innsbruck, Austria; Medical University of Innsbruck, Department of Haematology and Oncology, Innsbruck, Austria.

Reference: PLoS One. 2015 Feb 6;10(2):e0115537.
doi: 10.1371/journal.pone.0115537

PubMed Abstract
PMID: 25658878

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