Histopathological screening for prostate carcinoma: is a benign biopsy a negative biopsy?

The current value of histological findings in negative prostate biopsies to predict the future risk of clinically significant prostate cancer

BACKGROUND

Repeat prostate biopsy (PBx) is recommended under persistent suspicion of prostate cancer (PCa) or in the face of the following findings: atypical small acinar proliferation (ASAP); extense (≥3 biopsy sites) high-grade prostatic intraepithelial neoplasia (HGPIN); or HGPIN with atypical glands; suspicious for adenocarcinoma (PIN-ATYP). Nowadays; multiparametric magnetic resonance imaging (mpMRI) and mpMRI targeted PBx (MRI-TBx) are recommended in repeat PBx. Our objective was to analyze the current value of ASAP; mHGPIN; PIN-ATYP and other histological findings to predict clinically significant PCa (csPCa) risk.

METHODS

Retrospective analysis of 377 repeat PBxs. MRI-TBx was performed when Prostate Imaging-Reporting and Data System (PI-RADS) score >3 and 12-core transrectal ultrasound (TRUS) systematic PBx when ≤2. ASAP; HGPIN; mHGPIN; PIN-ATYP; and 8 other histological findings were prospectively reported in negative PBx. CsPCa was defined as ISUP group grade >2.

RESULTS

Incidence of ASAP; multifocal HGPIN (mHGPIN) and PINATYP was 4.2%; 39.7% and 3.7% respectively; and csPCa rate was statistically similar among men with these histological findings. However; the rate of csPCa was 22.2% when proliferative inflammatory atrophy (PIA) was present; and 36.1% when it was not. PIA was the only histological finding which predicted lower risk of csPCa; with an OR of 0.54 (95%CI: 0.308-0.945; P = .031). In addition; PIA was an independent predictor of a model combining clinical variables and mpMRI which reached area under de ROC curve of 0.86 (95%CI: 0.83-0.90).

CONCLUSION

PIA emerged as the only predictive histological finding of csPCa risk and can contribute to a predictive model. mHGPIN failed to predict csPCa risk. The low incidence of ASAP (4.2%) and PIN-ATYP (3.7%) prevented us from drawing conclusions.

The current value of histological findings in negative prostate biopsies to predict the future risk of clinically significant prostate cancer

INTRODUCTION

Repeat prostate biopsy (PBx) is recommended under persistent suspicion of prostate cancer (PCa) or in the face of the following findings: atypical small acinar proliferation (ASAP), extense (≥3 biopsy sites) high-grade prostatic intraepithelial neoplasia (HGPIN), or HGPIN with atypical glands, suspicious for adenocarcinoma (PIN-ATYP). Nowadays, multiparametric magnetic resonance imaging (mpMRI) and mpMRI targeted PBx (MRI-TBx) are recommended in repeat PBx. Our objective was to analyze the current value of ASAP, mHGPIN, PIN-ATYP and other histological findings to predict clinically significant PCa (csPCa) risk.

METHODS

Retrospective analysis of 377 repeat PBxs. MRI-TBx was performed when Prostate Imaging-Reporting and Data System (PI-RADS) score>3 and 12-core transrectal ultrasound (TRUS) systematic PBx when≤2. ASAP, HGPIN, mHGPIN, PIN-ATYP, and 8 other histological findings were prospectively reported in negative PBx. CsPCa was defined as ISUP group grade>2.

RESULTS

Incidence of ASAP, multifocal HGPIN (mHGPIN) and PINATYP was 4.2%, 39.7% and 3.7% respectively, and csPCa rate was statistically similar among men with these histological findings. However, the rate of csPCa was 22.2% when proliferative inflammatory atrophy (PIA) was present, and 36.1% when it was not. PIA was the only histological finding which predicted lower risk of csPCa, with an OR of .54 (95% CI: .308-.945, P=.031). In addition, PIA was an independent predictor of a model combining clinical variables and mpMRI which reached area under de ROC curve of .86 (95% CI: .83-.90).

CONCLUSIONS

PIA emerged as the only predictive histological finding of csPCa risk and can contribute to a predictive model. mHGPIN failed to predict csPCa risk. The low incidence of ASAP (4.2%) and PIN-ATYP (3.7%) prevented us from drawing conclusions.

Prediction of clinically significant prostate cancer after negative prostate biopsy: The current value of microscopic findings

OBJECTIVE

To assess the current ability of atypical small acinar proliferation (ASAP), multifocal high-grade prostatic intraepithelial neoplasia (mHGPIN), HGPIN with atypia (PINATYP) and other non-malignant lesions to predict clinically significant prostate cancer (csPCa) in repeat prostate biopsies.

METHODS

This retrospective study analyzed 377 repeat prostate biopsies, carried out between 2.014 and 2.017, and excluding those with previous PCa or 5-alpha reductase inhibitors treatment. ASAP, mHGPIN, PINATYP, prostatic atrophy, prostatic hyperplastic atrophy, proliferative inflammatory atrophy (PIA), chronic prostatitis, acute prostatitis, or granulomatous prostatitis, were prospectively reported after 12-core transrectal ultrasound (TRUS) systematic negative previous biopsies. 3T-multiparametric magnetic resonance imaging (mpMRI) was performed previous repeat biopsies. At least 2-core TRUS targeted biopsies of Prostate Imaging-Reporting and Data Systemv2 lesions ≥3, and/or 12-core TRUS systematic biopsy were performed in repeat prostate biopsies. The main outcome measurements were csPCa detection, which was defined when the International Society of Uro-Pathology group grade >1 and avoided biopsies. After logistic regression analysis the most efficient model was selected, nomogram was designed with internal validation, and clinical utility was analyzed.

RESULTS

Normal benign tissue alone was present in less than 2% of previous negative biopsies. mHGPIN (39.7%), ASAP (4.3%) and PINATYP (3.7%) failed to predict csPCa risk in repeat biopsies. The finding of PIA (38.2%) associated with a decreased the risk of csPCa with an Odd ratio of 0.54 (95% confidence interval: 0.31-0.95), P= 0.031. The area under the curve, to predict csPCa, of mpMRI was 0.736, increasing up to 0.860 (95% confidence internal:0.82-0.90) when PSA density, age, digital rectal examination, and differential PSA between biopsies and PIA finding were integrated in a predictive model. At 6% threshold, more than 20% of repeat prostate biopsies were saved without missing csPCa.

CONCLUSION

Currently, mHGPIN in negative prostate biopsy seems not able to predict the risk of future csPCa. The low incidence of ASAP and PINATYP, in our series, did not allow us to draw conclusions. PIA finding associated with a reduced risk of csPCa, and it could be integrated in a useful based-mpMRI predictive nomogram.

In Search for risk predictors at the microscopic scenario of a negative biopsy. A systematic review

INTRODUCTION

In cases of persistent suspicion of prostate cancer (PC), repeat prostate biopsies (PB) are frequently performed in spite of their low yield. In the context of a negative PB, there is a microscopic scenario (MS), which we define as the group of recognizable non-neoplastic lesions. While some of these lesions seem to have a protective effect, the existence of others increases the risk of PC detection in posterior PB. The objective of this systematic review is to identify the lesions that may belong to the MS of a negative PB and analyse the current evidence of their association with the risk of detecting PC in subsequent PBs.

EVIDENCE ACQUISITION

Two independent reviewers conducted a literature search on Medline, Embase and Central Cochrane with the following search terms: small acinar proliferation, ASAP, prostatic intraepithelial neoplasia, HGPIN, adjacent small atypical glands, pinatyp, atrophy, proliferative inflammatory atrophy, pia, prostatic inflammation, prostatitis and prostate cancer. 1,015 references were first identified, and 57 original articles were included in the study, following the PRISMA declaration and the PICO selection principles.

EVIDENCE SYNTHESIS

Atypical small acinar proliferation is associated with PC detection in repeat PB with rates ranging between 32 and 48%. High-grade prostatic intraepithelial neoplasia (HGPIN) is related to PC in 13 to 42% of cases. Studies show that HGPIN, when multifocal, is a significant independent risk factor for PC. Prostatic atrophy, inflammatory proliferative atrophy and prostatic inflammation seem to act as protective factors on the detection of PC in repeat PB. On the other hand, the risk of PC detection reduces significantly in male patients with multifocal HGPIN and coexistent PIA.

CONCLUSIONS

The MS of a negative PB may include atypical small acinar proliferation, HGPIN, prostatic atrophy, inflammatory proliferative atrophy and prostatic inflammation lesions, since they all seem to be associated with the risk of PC detection in repeat PB. This review has led us to create the hypothesis that the MS of a negative PB might be a valuable and useful tool when considering repeat PB.

Markers of clinical utility in the differential diagnosis and prognosis of prostate cancer

Molecular diagnostics is a rapidly evolving area of surgical pathology, that is gradually beginning to transform our diagnostical procedures for a variety of tumors. Next to molecular prognostication that has begun to complement our histological diagnosis in breast cancer, additional testing to detect targets and to predict therapy response has become common practice in breast and lung cancer. Prostate cancer is a bit slower in this respect, as it is still largely diagnosed and classified on morphological grounds. Our diagnostic immunohistochemical armamentarium of basal cell markers and positive markers of malignancy now allows to clarify the majority of lesions, if applied to the appropriate morphological context (and step sections). Prognostic immunohistochemistry remains a problematic and erratic yet tempting research field that provides information on tumor relevance of proteins, but little hard data to integrate into our diagnostic workflow. Main reasons are various issues of standardization that hamper the reproducibility of cut-off values to delineate risk categories. Molecular testing of DNA-methylation or transcript profiling may be much better standardized and this review discusses a couple of commercially available tests: The ConfirmDX test measures DNA-methylation to estimate the likelihood of cancer detection on a repeat biopsy and may help to reduce unnecessary biopsies. The tests Prolaris, OncotypeDX Prostate, and Decipher all are transcript tests that have shown to provide prognostic data independent of clinico-pathological parameters and that may aid in therapy planning. However, further validation and more comparative studies will be needed to clarify the many open questions concerning sampling bias and tumor heterogeneity.

[Intraductal carcinoma of the prostate]

For many tumor entities, especially in breast cancer, an intraductal carcinoma is generally perceived as a precursor lesion, which precedes the emergence of invasive carcinoma. Therefore, in addition to parameters of the invasive carcinoma, histological parameters of the intraductal component have always played an important role in therapy planning of breast cancer. This is different in prostate cancer and although the term "intraductal carcinoma" has long been propagated by some authors, its routine use remains rare and inconsistent. This is certainly not only due to the far simpler therapy options of prostate cancer, in which focal and organ-preserving therapies still play a subordinate role, but also due to substantial interobserver variation and our inconsistent perception of intraductal carcinomas. This article gives a brief overview of currently available literature on this topic and explains why intraductal carcinoma of the prostate deserves our attention. In contrast to breast cancer, intraductal carcinoma of the prostate usually represents a post-invasive lesion, in which an aggressive tumor exhibits spread into pre-existing ducts; however, in rare cases, intraductal carcinoma may represent a true precursor lesion.