Pathologic features the urologist should expect on a prostate biopsy

Diagnosis of prostate cancer using differentially expressed genes in stroma

More than one million prostate biopsies are performed in the United States every year. A failure to find cancer is not definitive in a significant percentage of patients due to the presence of equivocal structures or continuing clinical suspicion. We have identified gene expression changes in stroma that can detect tumor nearby. We compared gene expression profiles of 13 biopsies containing stroma near tumor and 15 biopsies from volunteers without prostate cancer. About 3,800 significant expression changes were found and thereafter filtered using independent expression profiles to eliminate possible age-related genes and genes expressed at detectable levels in tumor cells. A stroma-specific classifier for nearby tumor was constructed on the basis of 114 candidate genes and tested on 364 independent samples including 243 tumor-bearing samples and 121 nontumor samples (normal biopsies, normal autopsies, remote stroma, as well as stroma within a few millimeters of tumor). The classifier predicted the tumor status of patients using tumor-free samples with an average accuracy of 97% (sensitivity = 98% and specificity = 88%) whereas classifiers trained with sets of 100 randomly generated genes had no diagnostic value. These results indicate that the prostate cancer microenvironment exhibits reproducible changes useful for categorizing the presence of tumor in patients when a prostate sample is derived from near the tumor but does not contain any recognizable tumor.

Manganese superoxide dismutase (MnSOD) genetic polymorphism is associated with risk of early-onset prostate cancer

Prostate cancer continues to be the most frequently diagnosed neoplasm, and the second leading cause of cancer-related mortality in men. Oxidative stress may enhance prostatic carcinogenesis. Manganese superoxide dismutase (MnSOD) is the only known superoxide scavenger in mitochondria. It plays a key role in antioxidant defense as mitochondria are important for oxidative metabolism coupled to the electron transport chain and oxidative phosphorylation and hence, ROS production. A T-->C single nucleotide substitution, resulting in a Val-->Ala change at position 9 (Ala-9Val), which alters the secondary structure of the protein, has been noted to affect transport of MnSOD into the mitochondria. We have determined the MnSOD genotype in 85 prostate cancer cases and 151 control subjects. Ala-9Val polymorphism was determined using real time polymerase chain reaction (PCR) amplification with fluorescently labeled primers. No significant difference was found in prostate cancer susceptibility in the subjects with Ala/Ala and Val/Ala genotype compared with Val/Val genotype (Odds ratio (OR), 1.3; 95% confidence interval (95% CI), 0.69-2.42; p = 0.416). We did not observe an association of the MnSOD genotype or allele frequency between subgroups of cases divided by disease status (aggressive vs. non-aggressive prostate cancer). However, in the analyses stratified by the age at diagnosis we have observed that men homozygous for Ala had a 5.2-fold increased risk of early-onset prostate cancer (under age of 65) compared to men homozygous for Val allele (p = 0.05). These data suggest that Ala/Ala MnSOD genotype in the Macedonian population could have an influence on early onset of prostate cancer, but no impact on the subsequent development of the disease.

Saturation biopsy protocol enhances prediction of pT3 and surgical margin status on prostatectomy specimen

A 21-samples saturation biopsy procedure (SBP) was developed in order to improve prostate cancer detection rate. Out of 650 patients who underwent this protocol, 150 had a clinically localized prostate cancer and underwent a radical prostatectomy. The number of cores positive for tumor was assessed in the SBP, and also in the sextant component of the SBP (SC) and in the non-sextant component of the SBP (NSC). Numbers of cores positive for tumor on SBP, SC, and NSC were significantly higher in pT3 group versus pT2 (P < 0.001 each) and in positive surgical margins (PSM) group versus no PSM (P < 0.001 each). When comparing area under the curve obtained from SBP with those obtained from NSC and SC, the SBP showed higher accuracy than the NSC and the SC for the prediction of pT3 and PSM. On multivariate analyses, SC and NSC were independent predictors of pT3 and PSM on radical prostatectomy.

Significance of atypical and suspicious small acinar proliferations, and high grade prostatic intraepithelial neoplasia on prostate biopsy: implications for cancer detection and biopsy strategy

PURPOSE

We reviewed our results from a urological pathology reference laboratory with respect to the incidence of HGPIN, and atypical and suspicious lesions in the spectrum of ASAP. Subsequent CaP findings on repeat biopsy with relevant clinical implications were assessed.

MATERIALS AND METHODS

A review of 42,667 prostate biopsies was performed. We defined atypical and suspicious as variants of ASAP with suspicious being more worrisome for CaP. Findings were correlated with the location of CaP on repeat prostate biopsy.

RESULTS

The rate of subsequent CaP detection was significantly higher for an initial diagnosis of suspicious findings (51% or 54 of 107 cases) than for atypical findings (34% or 39 of 116) or HGPIN (22% or 79 of 358, p < 0.001). CaP was found on the same side of the prostate in 61 of 78 (78%), 30 of 39 (77%) and 41 of 54 patients (76%) with initial HGPIN, atypical and suspicious biopsies, respectively. There was no significant difference among the 3 groups in the likelihood of future CaP at the same site or the same side of the prostate.

CONCLUSIONS

Patients with a suspicious biopsy were significantly more likely to have CaP on future biopsy than those with atypical findings or HGPIN, suggesting that there may be divisions with prognostic significance in the larger category of ASAP. To our knowledge the reproducibility of recognizing such divisions remains to be established. Neither atypical nor suspicious lesions were more likely than HGPIN to predict CaP at the same site or side of the prostate as the original diagnosis. Repeat biopsy may be indicated in any patient with HGPIN, or atypical or suspicious lesions and this biopsy should not be limited to the site or side of the original pathological findings.

What Information are Urologists Extracting from Prostate Needle Biopsy Reports and What do They Need for Clinical Management of Prostate Cancer?

OBJECTIVES

This survey-based study examines what information urologists are extracting from prostate needle biopsy reports, and what they need for clinical management of prostate cancer (PC) patients.

METHODS

A questionnaire was used to investigate several topics related to PC biopsy reporting. Two different clinical situations were separately explored, depending on whether the urologist intended a curative or a palliative therapy.

RESULTS

110 of the 300 (37%) urologists responded to the questionnaire and returned anonymous responses. The mean age of respondents was 47.5 years old (range 27-66). On average, they performed 31 (range 0-182) radical prostatectomies per year. Before proposing a curative therapy, several biopsy parameters were requested by the majority of respondents, including number of positive biopsies (104/110 or 95%), Gleason score (103/110 or 94%), highest Gleason grade (94/110 or 85%), localization of positive biopsies (80/110 or 73%), length of tumor on biopsy (58/110 or 53%), presence of extraprostatic extension (66/110 or 60%). In a palliative situation, only three parameters were requested by the majority of respondents: Gleason score (101/110 or 92%), highest Gleason grade (67/110 or 61%) and number of positive biopsies (59/110 or 54%). In prostate needle biopsies harboring cancer on multiple cores from separately designated locations, 77% (68/88) of respondents used the highest Gleason score, regardless of the overall percentage involvement, to determine their treatment plan. PIN (Prostatic Intraepithelial Neoplasia) on biopsy without PC was considered sufficient to re-biopsy by 77% (85/110) of respondents. Thirty six percent (40/110) of the respondents considered ASAP (Atypical Small Acinar Proliferation) to be equivalent to PIN. There was no significant association between the demographic data and the type of information requested on the biopsy report.

CONCLUSIONS

In this sample of 110 French and Belgian urologists there was high variability in the way clinicians use prostate needle biopsy pathology report. Results of this survey should improve communication between urologists and pathologists and should help evaluate what data should be included in routine pathology reports.

Prostate needle biopsy reporting: how are the surgical members of the Society of Urologic Oncology using pathology reports to guide treatment of prostate cancer patients?

Recent trends in prostate needle biopsy reporting have resulted in the inclusion of more information and new diagnostic categories. The goal of the current study was to survey surgical Members of the Society of Urologic Oncology to determine what information academic urologists consider important in the management of their prostate cancer (PCa) patients. A questionnaire was developed to investigate several areas of PCa biopsy reporting, which vary from institution to institution. Urologists were sent questionnaires and asked to return anonymous responses; 42 questionnaires were completely evaluated with a response rate of 76% (42 of 55). The urologists targeted for this survey were highly experienced with an average of 22 years in clinical practice (range, 6-35 years). On average, they performed 92 radical prostatectomies per year and 449 over the past 5 years (range, 60-1500) for a group total of 18,840 radical prostatectomies; 94% have their patient's biopsy reviewed prior to surgery. The primary and secondary Gleason pattern was required by 60% (25 of 42) of the respondents. In prostate needle biopsies containing only a single minute focus of PCa, only 41% (17 of 42) of respondents would request a Gleason score if not provided in the initial report. Interestingly, in biopsies with multiple positive cores from separate locations, 81% (34 of 42) use the highest Gleason score, regardless of the overall percentage involvement, to determine their treatment plan. Other pathology parameters requested by the respondents in descending order included: % involvement of the core by PCa (67%), the presence or absence of perineural invasion (38%), the number of cores with PCa (33%), and the length of core involvement (29%). Only 24% (10 of 42) of respondents use perineural invasion status to guide nerve-sparing surgery. The more radical prostatectomies performed by a surgeon, the greater the likelihood that they considered perineural invasion clinically important (Mann-Whitney, two-tailed, P = 0.015). The term atypical small acinar proliferation was uniformly considered sufficient to re-biopsy by 98% (41 of 42) of the urologists. This is the first study to survey urologists as to what information they require from prostate needle biopsy reports in their treatment planning of men with clinically localized PCa. With the exception of Gleason score, the use of detailed pathology information was variably used to guide treatment. PNI was not considered important by the majority of respondents. In contrast, atypical small acinar proliferation, a more recent diagnostic category, was recognized as important by nearly all respondents. Knowledge of how pathology biopsy reports are being used should help evaluate what data should be uniformly part of standard biopsy pathology report and help improve communication between pathologists and urologists.