Incidental carcinoma of the prostate

The significance of the extent of tissue embedding for the detection of incidental prostate carcinoma on transurethral prostate resection material: the more, the better?

The aim of this study is to investigate the incidental prostate cancer (iPCa) detection rates of different embedding methods in a large, contemporary cohort of patients with bladder outlet obstruction (BOO) treated with transurethral surgery. We relied on an institutional tertiary-care database to identify BOO patients who underwent either transurethral loop resection or laser (Holmium:yttrium–aluminium garnet) enucleation of the prostate (HoLEP) between 01/2012 and 12/2019. Embedding methods differed with regard to the extent of the additional prostate tissue submitted following the first ten cassettes of primary embedding (cohort A: one [additional] cassette/10 g residual tissue vs. cohort B: complete embedding of the residual tissue). Detection rates of iPCa among the different embedding methods were compared. Subsequently, subgroup analyses by embedding protocol were repeated in HoLEP-treated patients only. In the overall cohort, the iPCa detection rate was 11% (46/420). In cohort A (n = 299), tissue embedding resulted in a median of 8 cassettes/patient (range 1–38) vs. a median of 15 (range 2–74) in cohort B (n = 121) (p < .001). The iPCa detection rate was 8% (23/299) and 19% (23/121) in cohort A vs. cohort B, respectively (p < .001). Virtual reduction of the number of tissue cassettes to ten cassettes resulted in a iPCa detection rate of 96% in both cohorts, missing one stage T1a/ISUP grade 1 carcinoma. Increasing the number of cassettes by two and eight cassettes, respectively, resulted in a detection rate of 100% in both cohorts without revealing high-grade carcinomas. Subgroup analyses in HoLEP patients confirmed these findings, demonstrated by a 100 vs. 96% iPCa detection rate following examination of the first ten cassettes, missing one case of T1a/ISUP 1. Examination of 8 additional cassettes resulted in a 100% detection rate. The extent of embedding of material obtained from transurethral prostate resection correlates with the iPCa detection rate. However, the submission of 10 cassettes appears to be a reasonable threshold to reduce resource utilization while maintaining secure cancer detection.

Prostate cancer screening by prostate-specific antigen (PSA); a relevant approach for the small population of the Cayman Islands

INTRODUCTION

The common tool for diagnosing prostate cancer is prostate-specific antigen (PSA), but the high sensitivity and low specificity of PSA testing are the problems in clinical practice. There are no proper guidelines to investigate the suspected prostate cancer in the Cayman Islands. We correlated PSA levels with the incidence of prostate cancers by tissue diagnosis and proposed logical protocol for prostate screening by using PSA test in this small population.

MATERIALS AND METHODS

A total of 165 Afro Caribbean individuals who had prostate biopsy done after the investigations for PSA levels from year 2005 to 2015 were studied retrospectively. The patients were divided into subgroups by baseline PSA levels as follows: <4, 4.1-10, 10.1-20, 20.1-50, 50.1-100, and >100 ng/mL and were correlated to the age and presence of cancer.

RESULTS AND DISCUSSION

Benign lesions had lower PSA levels compared to cancer which generally had higher values. Only three cases that had less than 4 ng/mg were turned out to be malignant. When PSA value was more than 100 ng/mL, all the cases were malignant. Between PSA values of 4-100 ng/mL, the probability of cancer diagnosis was 56.71% (76 cancers out of 134 in this range). Limitation of PSA testing has the risk of over diagnosis and the resultant negative biopsies owing to poor specificity. Whereas the cutoff limit for cancer diagnosis still remains 4 ng/mL from our study, most of the patients can be assured of benign lesion below this level and thus morbidity associated with the biopsy can be prevented. When the PSA value is greater than 100 ng, biopsy procedure was mandatory as there were 100% cancers above this level. On the background of vast literature linking PSA to prostate cancer and its difficulty in implementing in clinical practice, we studied literature of this conflicting and complex topic and tried to bring relevant protocols to the small population of Cayman Islands for the screening of prostate cancer. In this study, a total of 165 Afro Caribbean individuals who had prostate biopsy done after the investigations for PSA levels from year 2005 to 2015 were studied retrospectively. As a result of this research work, it can be concluded that a benign diagnosis can be given with a fair certainty when the PSA was below 4 ng/mL and a level of 100 ng/mL can be very unfavorable for the patients. This study helped to solidify the cancer screening protocols in Cayman Islands.

CONCLUSION

The PSA level can reassure and educate the patients towards the diagnosis of cancer of prostate in Cayman Islands. Benign diagnosis can be given with a fair certainty when the PSA was below 4 ng/mL and a level of 100 ng/mL can be very unfavorable for the patients. This study helped to solidify the cancer screening protocols in Cayman.

Successful treatment of incidental prostate cancer by radical transurethral resection of prostate cancer

BACKGROUND

To evaluate the rationale for RTUR-PCa against pT1a/b cancer, we analyzed oncological and functional outcomes.

PATIENTS AND METHODS

Fifty-six patients with incidental prostate cancer were included and the age ranged from 66 to 91 years (mean, 76.6; median, 75.0). Preoperative prostate specific antigen (PSA) levels were between 0.70 and 44.1 ng/mL (mean, 5.90; median, 4.60). We performed 69 RTUR-PCa's by resecting and fulgurating the residual prostate tissues after previous transurethral resection of the prostate. Prostate specific antigen nonrecurrence rate was calculated by Kaplan-Meier method.

RESULTS

Follow-up duration of 51 patients was mean ± SD 64.1 ± 21.6 months (median, 67.8 months; range, 13.8-99.8) excluding 5 patients that were lost to follow-up. Prostate specific antigen failure developed in 3 patients (5.9%). In the other 48 patients, PSA stabilized as follows: PSA ≤ 0.01, 24 cases; ≤ 0.02, 5 cases; ≤ 0.03, 6 cases; ≤ 0.04, 3 cases; ≤ 0.1, 7 cases; and ≤ 0.4, 3 cases. Prostate specific antigen nonrecurrence rates were 100% for pT2a and 91.3% for pT2b at the mean follow-up period of 64.1 months. Nonrecurrence rate grouped by D'Amico classification system were 100% in the low-risk group, 94.7% in the intermediate-risk group, and 88.2% in the high-risk group, respectively. Water intoxication did not develop and no patients required transfusion. Bladder neck contracture, which developed in 22 out of 51 patients (43.1%), was the most frequent postoperative complication. Postoperative incontinence was temporary and disappeared within 3 months in all patients.

CONCLUSION

Satisfactory oncologic and functional results suggest that RTUR-PCa could be a promising option for radical treatment against incidental prostate cancer.

Serum early prostate cancer antigen (EPCA) as a significant predictor of incidental prostate cancer in patients undergoing transurethral resection of the prostate for benign prostatic hyperplasia

BACKGROUND

Early prostate cancer antigen (EPCA), a nuclear matrix protein, has been recently suggested as a novel biomarker in malignant lesions of the prostate. This study was to determine whether preoperative serum EPCA levels predicted the presence of incidental prostate cancer (IPCa) in patients undergoing TURP for BPH.

METHODS

Serum EPCA levels were measured by ELISA in 449 consecutive patients with symptomatic BPH treated with TURP and 112 healthy men. Predictive performance of serum EPCA levels for IPCa were evaluated.

RESULTS

With a cutoff of 10ng/ml, serum EPCA protein had a 100% specificity for the healthy men and a 98% specificity and a 100% sensitivity in separating men with IPCa from those without. Serum EPCA levels in patients with IPCa were significantly higher than in those without and in healthy controls (17.63±2.42ng/ml vs. 5.58±1.61 ng/ml and 4.95±1.43 ng/ml, all P<0.001), whereas an indwelling transurethral catheter presence and 5α-reductase inhibitor therapy had no effect on EPCA levels (P=0.144 and P=0.238, respectively). The area under ROC curves (AUC) showed that serum EPCA level had the best predictive accuracy of all IPCa (AUC: 0.952, 95% CI: 0.912-0.981, P<0.001). Univariate and multivariate Cox regression analyses further demonstrated the independently predictive performance by preoperative serum EPCA (Hazards Ratio: 4.23, 95% CI: 3.62-6.46, P<0.001).

CONCLUSIONS

This study firstly shows that EPCA might be used as a highly sensitive and specific serum biomarker to predict IPCa presence and to help reduce the unnecessary biopsies taken before TURP in patients with BPH.

MUC1 expression in incidental prostate cancer predicts staging and grading on the subsequent radical prostatectomy

The behavior of Incidental prostate cancer (IPC) cannot be reliably predicted by means of conventional histomorphology. MUC1 (episialin) expression has been linked to poor outcome in peripheral prostate cancer (PC). We aimed to determine the so far neglected prognostic role of MUC1 expression in IPC which most commonly represents transition zone cancer. Using Tissue microarray (TMA), we assessed the association between MUC1 expression recorded in transurethral resection specimens of the prostate (TURP chips) and histopathologic outcome parameters (Gleason scores and histologic staging) performed on the subsequent radical prostatectomies (RPs) in a study cohort of 54 patients. Due to tissue loss during arraying and sectioning, a total of 44 (81.5%) tumor samples remained available for immunostaining which was dichotomized by two independent clinical pathologists as being absent or present. MUC1 expression was present in 7 (15.9%) of the 44 IPC immunohistochemically investigated with a striking over-representation in high stage tumors, and was significantly correlated with histopathologic staging (ρ = 0.4; p = 0.02) and Gleason scores (ρ = 0.3; p = 0.03) performed on the corresponding RPs. These data were confirmed by means of the McNemar test (staging: p = 0.01; grading: p = 0.04). Our findings suggest that MUC1 might become a valuable adjunct to enable individual prognostic ramification prior to radical surgery in prostate cancer histologically detected in TURP chips. This interesting observation clearly awaits validation by larger studies surveying clinical follow-up data.

Expression of prostatic acid phosphatase (PSAP) in transurethral resection specimens of the prostate is predictive of histopathologic tumor stage in subsequent radical prostatectomies

Clinical management of incidental prostate cancer (IPC) remains challenging since its clinical course cannot be predicted by conventional histopathology. Aiming to define predictive factors in IPC, we correlated the immunohistochemically detected expression of prostate-specific antigen (PSA), prostatic acid phosphatase (PSAP), alpha-methylacyl-CoA racemase (AMACR, p504s), and androgen receptor in transurethral resection specimens with Gleason scores and histologic staging on the corresponding radicals in a cohort of 54 patients (mean age, 65.9 years; range, 49-80 years). PSAP expression showed a significant correlation with tumor staging (rho = -0.37; p = 0.02) but not with Gleason scores (rho = -0.06; p = 0.69). K-statistics revealed a highly significant moderate interobserver agreement concerning the evaluation of PSAP staining (K = 0.47; p < 0.001). In contrast, the other markers assessed failed to correlate with conventional histopathology. Therefore, PSAP might be predictive of tumor stage in IPC and represent a valuable adjunct for clinical decisions in terms of individual therapeutic management.

How much tissue sampling is required when unsuspected minimal prostate carcinoma is identified on transurethral resection?

CONTEXT

When minimal prostate cancer is detected in the initial transurethral resection of the prostate (TURP) sample, it is uncertain how extensively the remaining tissue should be sampled for accurate grading and staging.

OBJECTIVE

To identify whether additional partial or complete sampling is required to accurately evaluate TURP samples with minimal cancer (stage T1a).

DESIGN

We prospectively examined all TURP samples in our institution during 1 year. All specimens were sampled randomly in 6 cassettes. When minimal cancer was found, we performed additional partial sampling (1 block per 5 g of remaining tissue), followed by complete submission of all remaining tissue. All samples were evaluated separately to identify possible changes in Gleason score and tumor volume. We performed a cost analysis for the additional tissue sampling.

RESULTS

Of 747 TURP samples evaluated on the initial 6 cassettes, 125 (16.7%) contained prostate cancer. Minimal cancer involving less than 5% of sampled tissue was found in the initial submission in 26 (3.5%) patients. Additional partial examination required 3.5 blocks per case (median; range, 1-23), while complete processing required an additional 5.5 blocks per case (median; range, 2-25). Initial Gleason scores and tumor volumes were not changed in any of the studied cases after evaluating the additional partial and complete samples. In our laboratory, we calculated a cost of $4336 per year for the additional sampling of TURPs with minimal cancer ($1681 for partial and $2655 for complete sampling).

CONCLUSIONS

When minimal cancer was found in the first 6 cassettes of transurethral resections, additional partial and complete sampling did not change the initial Gleason scores and tumor volumes.

Predictive Factors for Progression in Patients with Clinical Stage T1a Prostate Cancer in the PSA Era

OBJECTIVE

In the literature, most data regarding the outcome of patients with clinical stage T1a prostate cancer were established before the prostate-specific antigen (PSA) era. The aim of our study was to determine the predictive factors of progression in patients with T1a prostate cancer diagnosed in the PSA era.

METHODS

Consecutive patients (n=144) with newly diagnosed T1a prostate cancer (tumor involving < or =5% of the resected prostatic tissue) were included. None of them was treated before evidence of tumor progression confirmed by prostate needle biopsies. The associations between tumor characteristics and time to cancer progression were assessed using Cox regression analysis.

RESULTS

With a mean follow-up of 5.1 yr, 30 patients (21%) experienced cancer progression. Five adverse parameters were significantly associated with cancer progression: preoperative PSA> or =10 ng/ml, postoperative PSA> or =2 ng/ml, prostate weight > or =60 g, weight of resected tissue > or =40 g, and Gleason score> or =6. The 5-yr progression rate was 12% if fewer than two of these parameters were present, whereas it was 47% if two or more parameters were present (p<0.001).

CONCLUSION

In the PSA era the risk of progression associated with T1a prostate cancer can be predicted using five criteria, and two groups of patients can be defined. The patients at low risk of progression may be good candidates for surveillance. In those with a high risk of progression, a more aggressive treatment should be discussed.

Prognostic Value of DNA Ploidy, bcl-2 and p53 in Localized Prostate Adenocarcinoma Incidentally Discovered at Transurethral Prostatectomy

PURPOSE

Discovery of prostatic adenocarcinoma limited to transurethral resection material generates a treatment dilemma. We investigated the usefulness of parameters shown to be associated with prognosis in prostate cancer (p53 and bcl-2 immuno-expression, DNA cell cycle analysis and Gleason score) to stratify these incidentally identified tumors to guide clinical decision making.

MATERIALS AND METHODS

Paraffin embedded tissues from transurethral prostate resection specimens containing T1a prostate adenocarcinoma from 44 patients who underwent resection between 1980 and 1990 were immunostained for p53 and bcl-2, and subjected to flow cytometry to determine DNA ploidy. Gleason score was determined by 2 pathologists independently. Statistical relationships among these 4 variables, tumor progression and cancer specific survival were analyzed.

RESULTS

Six of 44 patients in the study population had cancer progression. Time to clinical progression was 4.5 years (range 7 months to 11 years). Most tumors stained negative for p53 and bcl-2. Only 2 tumors studied were aneuploid and neither of these 2 patients had cancer progression. Only Gleason score was a significant predictor of cancer progression on univariate and multivariate Cox regression analysis (p = 0.045 and 0.046, respectively). No tumor characteristics correlated with time to disease progression, including p53 and bcl-2 immuno-expression, and Gleason score (p = 0.182, 0.563 and 0.346, respectively). Positive immunostaining for p53 and bcl-2 did not occur together in the same tumor in significant fashion (p = 0.334), nor did either significantly occur more with aneuploidy (p = 0.237 and 0.307 respectively).

CONCLUSIONS

For T1a prostate cancer incidentally detected on transurethral prostate resection p53 and bcl-2 immuno-expression, and DNA ploidy do not predict survival or disease progression.

[Clinicopathological study of incidental cancer prostate in patients undergoing surgery for symptomatic diagnosis of BPH]

OBJECTIVES-INTRODUCTION: Retrospective study of a series of patients with prostate surgery (suprapubic prostate adenomectomy -APS-, and prostate transurethral resection -RTU-P-) for presumed BPH symptomatic non-respondent to the conservative medical treatment. Analysis of prevalence, incidence, clinical-pathological, treatment, tumor progression and evolution of the patients with incidental prostate cancer (CPI) detected.

MATERIAL AND METHODS

1593 patients with prostate surgery (APS and RTU-P) during 6 years (1996-2001) were revised. APS 35%, RTU-P 65%. Revision of all pathological anatomy of surgical specimens and the evolutions of the patients with CPI.

RESULTS

78 CPI; Prevalence 4,89%; Incidence 13 cases/year. Mean age 73.6 years. Digital rectal examination was normal in 100%, mean PSA 6 ng/ml (0.5-30). Group APS: 25 CPI (32%); prevalence 4.55%; incidence 4 cases/year; mean PSA 7.7 ng/ml (2.8-30); mean weight resection 65 gs. Group RTU-P: 53 CPI (68%); prevalence 5,07%; incidence 9 cases/year; mean PSA 5.2 ng/ml (0,5-29); mean weight resection 20 gs. 22% biopsy previously by high PSA, mean PSA 14 ng/ml (4,8-30). Gleason average 5 (mean 4.8), rank 3-8. pTla 66%, pTlb 33%.

TREATMENT

57% follow-up watched without treatment (wait and see); 18% hormonal treatment; 3% finasteride; 9% Radical Prostatectomy; 9% radiotherapy. Follow Lost 4%. Mean follow-up 47.19 months (12-96). Tumor progression 13.3% (10 patients). Specific CPI mortality 2.6% (2 patients).

CONCLUSIONS

We didn't observe significant differences between the prevalence of CPI in both groups (APS and RTU-P). The detected tumours were mainly well differentiated and in stage pTla. In more than half of the cases an expectant attitude without treatment was decided. 13,3% of tumor progression after 47.19 months of follow mean and specific CPI mortality 2.6%.

Did the rate of incidental prostate cancer change in the era of PSA testing? A retrospective study of 1127 patients

OBJECTIVES

To evaluate, in a retrospective study, the impact of routine prostate-specific antigen (PSA) testing on the rate of incidental prostate cancer in patients undergoing surgery for obstructive symptoms caused by presumed benign prostatic enlargement (BPE) and to investigate the indication of a routine biopsy before alternative treatment procedures for BPE. In the pre-PSA era, the diagnosis of incidental carcinoma was exclusively based on normal digital rectal examination (DRE) findings.

METHODS

Since January 1993, 2422 operations (2283 transurethral resection of the prostate, 139 retropubic adenoma enucleations) for BPE were performed at our institution. The preoperative DRE findings and PSA level were evaluated, and patients with any suspicion for cancer were excluded. The pathologic reports of all patients were reviewed. A diagnosis of incidental carcinoma of the prostate required histologic evidence of cancer and negative DRE findings and a PSA level within age-specific reference ranges preoperatively.

RESULTS

Of 2422 patients, 1127 (46.5%) had both negative DRE findings and an age-specific PSA level and were evaluated for our study. Overall, prostate cancer was diagnosed by surgery in 314 (13%) of 2422 patients. The rate of incidental prostate cancer in patients with both negative age-specific PSA levels and negative DRE findings was 6.4% (72 of 1127).

CONCLUSIONS

In our series, the likelihood of detecting incidental prostate cancer by surgery was 6.4%. In the PSA era, the rate of incidental prostate cancer has been decreased by more than 50%. Today, the low rate of incidental carcinoma does not warrant routine histologic evaluation of the prostate if PSA testing and DRE are negative when alternative treatment modalities without tissue sampling are offered for the treatment of BPE.

Clinically unsuspected and undetected (clinical stage t0) prostate cancer diagnosed on random needle biopsy

OBJECTIVES

To describe the findings in 4 patients who underwent radical prostatectomy for clinically undetected and unsuspected prostate cancer detected on random needle biopsy.

METHODS

We reviewed the Mayo Clinic Radical Prostatectomy Prostate Cancer Database of 5793 prostatectomies from 1987 to 1997, and identified 4 patients who had prostate cancer detected on random needle biopsy of the prostate with serum prostate-specific antigen (PSA) less than 4 ng/mL and normal digital rectal examination. Each had requested biopsy despite the absence of clinical suspicion of cancer; 3 had normal transrectal ultrasound, and the fourth had a benign hypoechoic lesion contralateral to the cancer.

RESULTS

Mean patient age at diagnosis was 65.5 years (range 61 to 67). Mean PSA was 2.4 ng/mL (range 2 to 2.9). Mean tumor volume was 3 cc (range 0.04 to 11.2). Mean Gleason grade at prostatectomy was 5.75 (range 5 to 7). Prostate cancer was Stage T2a in 1 patient (25%), T2c in 2 (50%), and T3a (25%) in 1. Three tumors were DNA diploid, and one was aneuploid. All patients were alive without evidence of cancer at a mean follow-up of 43 months (range 25 to 53) with undetectable serum PSA concentration.

CONCLUSIONS

Our findings indicate that clinically unsuspected and undetected (clinical Stage T0) prostate cancer may be clinically significant. Patient insistence on biopsy reflects increasing concern among the public about prostate cancer. Current clinical thresholds for biopsy detection will fail for some patients with clinically significant prostate cancer.

Prostate-specific antigen utilization in Ontario: extent of testing in patients with and without cancer

OBJECTIVES

To ascertain the extent of prostate-specific antigen (PSA) testing in patients with prostate cancer (PC), with other cancers (OC), and with no cancer (NC) in two clinical laboratory databases.

DESIGN AND METHODS

PSA test records were obtained from a tertiary care hospital, Sunnybrook Health Science Centre (SHSC) and from a private laboratory, Gamma-Dynacare Medical Laboratories (GDL), during the period 1988 to 1995. These records were linked with the Ontario Cancer Registry (OCR) to establish a diagnosis of PC, OC, or NC. Trends in PSA testing according to diagnostic category, testing laboratory, patient age (by decade), and PSA value (in microgram/L) were determined.

RESULTS

Major cancer sites identified in the patients tested for PSA were prostate (60%), bladder and colon (7% each), lung (5%), kidney (3%), and rectum (3%). There were 11,867 patients (8.5%) with PC, 8,002 (5.9%) with OC, and 118,954 (86%) with NC. The total number of PSA tests performed on these patients was 230,756, of which 21% were on PC, 5% on OC, and 74% on NC; of these tests, 64% were performed through GDL and 36% through SHSC. The mean (median) number of tests per patient was: PC, 4.0 (2); OC, 1.4 (1); and NC, 1.5 (1). For PC 89% and for OC 72% of all tests occurred after diagnosis. Between 1990 and 1995 the number of PSA tests increased two-fold in PC and OC, and 20-fold in NC. We estimate that about one-half of the PSA tests in the NC group were for screening purposes. The proportion of PSA tests occurring in PC, OC, and NC for patients 50 to 70 years of age was 41%, 50%, and 63%, respectively; for patients over 70 years of age, this proportion was 58%, 46%, and 22% respectively; and for patients under 50 it was 1%, 4%, and 15%, respectively. Between 1990 and 1995, the largest increase in testing frequency was in the NC group, particularly in patients 50 to 70 years of age, which was accompanied by a decrease in patients over 70. Less than 10% of testing occurred in patients under 50 in all diagnostic groups. We estimate that about 26% of PSA screening tests in NC occurred outside the guidelines for patient age. Between 1988 and 1995, the proportion of PSA results below our detection limit (< 0.2 micrograms/L) showed a steady rise in the PC group, as did the proportion between 0.2 and 3.9 micrograms/L; these were accompanied by a fall in the proportion > 20.0 micrograms/L. However, the proportion of PSA results within these ranges did not change much during the same time period for the OC and NC groups. At cutoffs of PSA = 4.0 micrograms/L (or PSA = 10.0 micrograms/L), estimates of clinical specificity were 84.0% (or 96.3%), and of clinical sensitivity were 83.4% (or 47.1%).

CONCLUSIONS

Most (86%) PSA testing occurred in men with NC, consistent with diagnosis or screening. There were more PSA tests per patient in PC than in OC, and most testing occurred after diagnosis. PSA testing in the NC group continues to increase rapidly. The proportion of PSA tests in patients over age 70 decreased in the order of PC > NC > OC. Between 1990 and 1995, there was an increase in the proportion of patients tested who were between 50 and 70 in the NC group, which may suggest more screening in this group. Over this same time period, there was an increase in the proportion of undetectable PSA values, possibly suggesting increased use of radical therapy; there was also a decrease in the proportion of PSA > 20 micrograms/L, possibly suggesting a decrease in the prevalence of advanced stage PC.