Adherence of the indication to European Association of Urology guideline recommended pelvic lymph node dissection at a high-volume center: Differences between open and robot-assisted radical prostatectomy

PURPOSE

Contemporary adherence of the indication to European Association of Urology (EAU) guideline recommendation for pelvic lymph node dissection (PLND) at either open (ORP) or robot-assisted radical prostatectomy (RARP) at a high-volume center is unknown. To assess guideline recommended and observed PLND rates in a high-volume center cohort.

METHODS

We relied on the Martini-Clinic database and focused on patients treated with either ORP or RARP, between 2010 and 2013. Actual performed PLND was compared to European Association of Urology (EAU) guideline recommendation defined by nomogram predicted risk of lymph node invasion >5%. Categorical and multivariable logistic regression analyses targeted two endpoints: 1) probability of guideline recommended PLND and 2) probability of no PLND, when not recommended by EAU guideline.

RESULTS

Within 7868 PCa patients, adherence to EAU PLND guideline recommendation was 97.1% at ORP and 96.8% at RARP (p = 0.7). When PLND was not recommended, it was more frequently performed at RARP (71.6%) than at ORP (66.2%) (p = 0.002). Gleason score, PSA and number of positive biopsy cores were independent predictors for both either PLND when recommended, or no PLND when not recommended (all p < 0.05). Clinical tumor stage, age and surgical approach were also independent predictors for no PLND when not recommended (all p < 0.05).

CONCLUSIONS

Adherence of the indication to EAU guideline recommended PLND is high at this high-volume center. Neither ORP nor RARP represent a barrier for PLND, when recommended. However, a high number of patients underwent PLND despite absence of guideline recommendation. Possible staging advantages and PLND related complications needs to be individually considered, especially, when LNI risk is low.

[Technical aspects of nerve sparing during retropubic prostatectomy]

Retropubic radical prostatectomy is the most commonly used therapeutic option for the treatment of clinically localized prostate cancer. An ongoing stage migration towards organ-confined cancers allows performing a nerve-sparing procedure in a growing number of patients. Key elements for achieving convincing functional results are a sphincter preserving Ligation of the distal part of Santorini's plexus and the subtle preparation of the neurovascular bundle. This article gives a detailed description of the operative technique. Furthermore, a strategy for patient selection and tumour selection for the indication of nerve-sparing radical prostatectomy (NSRP) is suggested.

Transition zone cancers undermine the predictive accuracy of Partin table stage predictions

PURPOSE

The Partin tables represent the most widely used predictor of pathological stage in men with localized prostate cancer (PCa). The accuracy and performance of the tables have been tested across different populations. However, to our knowledge the potential limitations that may stem from differences between transition zone (TZ) and peripheral zone (PZ) prostate cancers has not been explored. We tested the predictive accuracy and performance of the Partin tables according to TZ vs PZ tumor predominance.

MATERIALS AND METHODS

Preoperative serum prostate specific antigen, clinical stage and biopsy Gleason sum data on 1,990 patients treated with radical retropubic prostatectomy were used to define the 2001 Partin probabilities of organ confinement and seminal vesicle invasion (SVI). Data on 1,320 patients who underwent staging pelvic lymphadenectomy and radical retropubic prostatectomy were used to define the probabilities of lymph node invasion (LNI) and organ confined disease (OC). ROC area under the curve was used to assess the predictive accuracy of the 2001 Partin tables relative to observed extracapsular extension (ECE), SVI, LNI and OC. Performance characteristics for each prediction were explored graphically with local regression, nonparametric smoothing plots. Results were compared between 222 TZ cancers and 1,768 PZ cancers.

RESULTS

The 1,990 radical retropubic prostatectomy specimens demonstrated ECE in 689 cases (34.6%) (TZ in 58 or 27.1% and PZ in 631 or 35.8%) and SVI in 224 (TZ in 13 or 6.1% and PZ in 211 or 11.9%). The 1,320 lymphadenectomy specimens demonstrated LNI in 56 cases (TZ in 2 or 0.9% and PZ in 54 or 4.6%). OC was found in 784 cases (59.4%) (TZ in 95 or 69.9% and PZ in 689 or 58.2%). Predictive accuracy was for ECE 76.4% (TZ 69.0% and PZ 77.2%), 78.0% for SVI (TZ 73.5% and PZ 78.3%), 78.6% for LNI (TZ 44.5% and PZ 79.9%) and 79.4% for OC (TZ 73.8% and PZ 80.0%).

CONCLUSIONS

The biological tumor characteristics of TZ PCa differ from those of PZ PCa. These differences appear to undermine the accuracy of pathological stage predictions.

Isoformen des freien prostataspezifischen Antigens

Detection of prostate-specific antigen remains the mainstay in the early detection of prostate cancer. A problem yet unsolved is the lack of specificity of this organ- but not cancer-specific marker, which generates subsequent, invasive procedures in a high number of patients without detecting prostate cancer. While the separate detection of free PSA and the ratio of free to total PSA has significantly improved specificity while maintaining high sensitivity, the number of patients undergoing unnecessary further diagnostics is still of concern. In this context, the evolving knowledge on isoforms of free PSA is a major focus of current research. Isoforms of free PSA are variants of free PSA that circulate, e.g., as precursor forms, internally cleaved variants of intact molecules, and are suggested to be either more associated with cancer or more with benign diseases. This article describes biochemical and clinical properties of the isoforms of free PSA.

[Transrectal ultrasound-guided punch biopsies of the prostate. Indication, technique, results, and complications]

The golden standard for diagnosis of prostate cancer is transrectal ultrasound-guided systematic biopsy (TRUS-Bx). The optimal number of cylinders, sampling design, and indications for repeat biopsy are still in a state of flux. At the beginning of the 1980s, considerable doubts persisted regarding the benefit of ultrasound-guided punch biopsy for the diagnosis of prostate cancer. The examination on a chair with a fixed ultrasound head caused the patient substantial discomfort. Besides, in the pre-PSA era, most prostate carcinomas were detected by palpation and digitally guided biopsies were easily obtained. Indeed, the DRU procedure alone exhibited low sensitivity. Keetch et al. found that in only 25% of patients with abnormal palpatory findings and PSA between 4 and 20 ng/ml was a carcinoma revealed upon biopsy. On the other hand, patients with suspicious palpatory findings and proven malignancy suffered more frequently from locally advanced and systemic metastasizing tumors. As a result of restaging based on PSA, in most series more than half of the detected carcinomas presented normal palpatory findings. Ultrasound examination made precise imaging of zonal structures possible and thus offered the advantage of precision guidance for tissue biopsy despite lower sensitivity and specificity for diagnosis of suspicious lesions. Furthermore, calculation of prostate volume was possible. At the end of the 1980s, Hodge defined the systematic sextant biopsy as the first golden standard for early detection of prostate cancer. This meant the systematic removal of three punch cylinders from both lateral lobes of the prostate in the parasagittal midline at various levels (apex, middle, and base).

Indikationstellung und Ergebnisse der radikalen Prostatektomie

Radical prostatectomy represents the mainstay of therapy for clinically localized prostate cancer. The combination of diagnostic parameters such as PSA or biopsy Gleason grade in nomograms allows a safe prediction of pathologic stage and prognosis of the disease. Imaging techniques are useful in a subset of patients. International studies have proven a high cancer control rate of radical prostatectomy. A nerve-sparing modification of the operative technique does not compromise radicality of the procedure if patients are carefully selected. For this purpose simple and reliable algorithms are available.

Serummarker in der Fr�herkennung und dem Staging des Prostatakarzinoms

Prostate-specific antigen (PSA) is by far the most important tumor marker in urology and has revolutionized early detection, staging, treatment, and aftercare of prostate cancer [77]. Despite these merits, inadequacies have surfaced which prohibit characterizing PSA as a perfect tumor marker. First, PSA is not a marker for prostate cancer as such:benign prostate hyperplasia, prostatitis [40,69], or prostatic manipulation [66] influence serum concentrations of PSA and lead to biopsies that are costly and potentially harmful. In the entire PSA range between 4 and 10 ng/ml, the specificity at a sensitivity of 95% continues to remain unsatisfactory. Furthermore, 30-40% of all men develop prostate cancer, but only 9-11% a clinically significant tumor burden, and 2.5-4.3% of all men die from prostate cancer. The vast majority of all carcinomas are thus in significant in terms of the patient's life expectancy. PSA is incapable of differentiating these clinically insignificant carcinomas from significant ones. Finally, prevalence of prostate cancer is increasing due to higher life expectancy. On the other hand, particularly patients aged 50-70 years are the ones who develop an aggressive form of carcinoma and profit from early detection and treatment. The global term "total PSA"encompasses a heterogeneous blend of bound and free molecular forms of PSA. Complexed PSA represents the major form of total PSA. The smaller portion, free PSA, is enzymatically inactive. In addition, different isoforms of free PSA exist Recent studies provide support for clinical application of these isoforms for early detection of prostate cancer. Clinical measurement of human glandular kallikrein 2 (hK2) serves as a complementary marker to PSA for early detection of prostate cancer and constitutes a considerable improvement over PSA as a staging marker for clinically localized prostate cancer. This overview summarizes established and potentially new forms of PSA and hK2 for early detection and staging of prostate cancer.

[Can nomograms derived in the U.S. applied to German patients? A study about the validation of preoperative nomograms predicting the risk of recurrence after radical prostatectomy]

In patients suffering from prostate cancer, preoperative nomograms, which predict the risk of recurrence may provide a helpful tool in regard to the counselling and planning of an appropriate therapy. The best known nomograms were published by the Baylor College of Medicine, Houston and the Harvard Medical School, Boston. We investigated these nomograms derived in the U.S. when applied to German patients. Data from 1003 patients who underwent radical prostatectomy at the University-Hospital Hamburg were used for validation. Nomogram predictions of the probability for 2-years (Harvard nomogram) and 5-years (Kattan nomogram) freedom from PSA recurrence were compared with actual follow-up recurrence data using areas under the receiver-operating-characteristic curves (AUC). The recurrence free survival after 2 and 5 years was 78% and 58%, respectively. The AUC of the Harvard nomogram predicting 2-years probability of freedom from PSA recurrence was 0.80 vs. Kattan-Nomogram 5-years prediction of 0.83. Thereby, the Kattan nomogram showed a significant higher predictive accuracy (p=0.0274). For that reason preoperative nomograms derived in the U.S. can be applied to german patients. However, we would recommend the utilization of the Kattan nomogram due to its higher predictive accuracy.

Differences in biopsy features between prostate cancers located in the transition and peripheral zone

OBJECTIVE

To identify the zonal location of prostate cancers before surgery, by analysing the mapping of ultrasonography-guided systematic sextant biopsies for differences between cancers located in the transition zone (TZ) and peripheral zone (PZ); and to compare the correlation between Gleason scores of needle biopsies and those of radical prostatectomy (RP) specimens.

PATIENTS AND METHODS

In all, 186 patients with TZ (46) and PZ cancers (140) underwent ultrasonography-guided systematic sextant biopsy and RP at the same institution. The clinical and pathological characteristics, and the anatomical location of positive biopsies, were determined and compared using t-tests and chi-square tests. Differences between Gleason scores of needle biopsies and those of RP specimens were evaluated and compared by Cohen kappa testing.

RESULTS

TZ cancers had a significantly lower rate of positive biopsies in the middle (63% vs 80%) and base (50% vs 80%) of the prostate than had PZ cancers. Positive biopsies were exclusively obtained from the apex in 19.6% of TZ and 5% of PZ cancers (P = 0.002). There was exact agreement between Gleason scores of needle biopsies and those of RP specimens in 15.2% of TZ (kappa = 0.02) and 55% of PZ cancers (kappa = 0.25), respectively.

CONCLUSION

Compared with PZ cancers, TZ cancers had a different anatomical pattern of positive biopsies, with lower rates in the middle and base of the prostate. The finding of positive biopsies exclusively in the apex favoured prostate cancer located in the TZ. Furthermore, the correlation between needle biopsy Gleason scores and those of the RP specimens was clearly lower in TZ cancers.

Human glandular kallikrein 2 levels in serum for discrimination of pathologically organ-confined from locally-advanced prostate cancer in total PSA-levels below 10 ng/ml

BACKGROUND

We measured serum levels of human glandular kallikrein 2 (hK2) in patients treated with radical retropubic prostatectomy (rrP) for clinically localized prostate cancer (PCa) with a total PSA (tPSA)-level below 10 ng/ml to investigate whether hK2 can be applied to preoperatively distinguish organ-confined (pT2a/b) from nonorgan-confined (> or = pT3a)-PCa more accurately than total PSA. Further, we evaluated hK2, free- and tPSA-concentrations in all pathologic stages of PCa.

METHODS

161 serum samples from men scheduled for rrP were collected 1 day before surgery prior to any prostatic manipulation. Pathologic work-up revealed > or = pT3a-PCa in 48 and pT2a/b-PCa in 113 patients. HK2-levels in serum were measured using an immunofluorometric assay with an analytical sensitivity of 0.5 pg/ml, a functional sensitivity of 5 pg/ml and insignificant cross-reactivity with PSA (< 0.005%). Total (tPSA) and free PSA (fPSA) levels were measured using a commercially available assay from which we calculated %fPSA and an algorithm that combined hK2 and PSA-levels [hK2] x [tPSA/fPSA]. Means, medians, and ranges were calculated for pT2a/b vs. >/= pT3a-PCa and for all pathologic stages. Statistical significance of differences was calculated using Mann-Whitney-U and Kruskal-Wallis tests. Calculation of receiver-operator-characteristic (ROC) curves were performed for hK2, [hK2] x [tPSA/fPSA] and tPSA to compare diagnostic performance.

RESULTS

A mean tPSA level in serum of 6.12 ng/ml in > or = pT3a-PCa was not significantly different (P = 0.366) from 5.78 ng/ml in pT2a/b-PCa. Also, there were no statistically significantly different levels of fPSA (P = 0.947) or %fPSA (0.292) for these two groups. By contrast, mean hK2-level in pT2a/b-PCa of 80 pg/ml was significantly different (P = 0.004) from a mean hK2 level of 120 pg/ml in > or = pT3a-PCa as shown by Mann-Whitney-analysis Moreover, the algorithm of [hK2] x [tPSA/fPSA] was significantly lower (P = 0.0004) in pT2a/b-PCa vs. > or = pT3a-PCa. Calculation of areas under curve (AUC) by receiver-operator-characteristics (ROC) demonstrated that the AUC for hK2 (0.64) was larger and the AUC for [hK2] x [tPSA/fPSA] (=0.68) significantly larger (P = 0.007) compared to the AUC of tPSA (0.55). Furthermore, Kruskal-Wallis Test revealed a highly significant correlation to pathologic stage using hK2 (P = 0.008) and [hK2] x [tPSA/fPSA] (P = 0.0015) compared to no significant differences in serum concentration of tPSA (P = 0.296). Also at tPSA-levels from 10-20 ng/ml, the hK2-levels in pT2a/b-PCa were close to significantly different (P = 0.051) from those in men with >/= pT3a-PCa, while the algorithm of [hK2] x [tPSA/fPSA] in that tPSA-range was significantly lower (P = 0.002) in pT2a/b-PCa compared to > or = pT3a0-PCa.

CONCLUSIONS

Highly significant differences in serum concentration enable hK2 to be a powerful predictor of organ-confined disease and pathologic stage of clinically localized prostate cancer, especially in the PSA-range below 10 ng/ml. As such, there are important clinical consequences for the application of hK2 for the adequate treatment of prostate cancer patients, i.e., the option of nerve-sparing surgery. (c) 2001 Wiley-Liss, Inc.

[Nerve-sparing radical retropubic prostatectomy. Results of a patient survey]

Improved selection criteria have led to an increasing number of nerve-sparing radical retropubic prostatectomies (RRP) in patients with clinically localized prostate cancer. The results based on patient questionnaires regarding postoperative erectile function are described. Between January 1992 and March 1999, 366 patients (mean age: 62.5 years) underwent uni- or bilateral nerve-sparing RRP at our institution. For evaluation of postoperative patient-reported rates of sexual and erectile function, a questionnaire was used after a follow-up of at least 12 months. Data of five operation periods were analyzed. The results of the unilateral procedure for the five operation periods revealed consistent rates of 13-29% for erections sufficient for intercourse. Bilateral nerve-sparing procedures were almost exclusively performed in periods 3 to 5; only four patients from period 2 underwent the bilateral procedure. The rates of intercourse-sufficient erections were 25% (period 2), 61% (period 3), 50% (period 4), and 52% (period 5), respectively. The results of the unilateral procedure were disappointing. However, the bilateral nerve-sparing method achieved much better results inasmuch as about 50% of the patients reported recovery of erections sufficient for sexual intercourse.

A validated strategy for side specific prediction of organ confined prostate cancer: a tool to select for nerve sparing radical prostatectomy

PURPOSE

Nerve sparing radical prostatectomy for prostate cancer should be restricted to patients who harbor tumors without capsular penetration. To our knowledge the selection criteria for nerve sparing radical prostatectomy are not clearly defined. We investigated a panel of preoperative tumor characteristics with respect to their ability to predict organ confined tumor growth for each lobe of the prostate to indicate unilateral or bilateral nerve sparing radical prostatectomy.

MATERIALS AND METHODS

Nine preoperative tumor characteristics in 278 patients with clinically localized prostate cancer were included in retrospective univariate and multivariate tree structured regression analysis. The association of clinical stage, serum prostate specific antigen (PSA), PSA density, and results of transrectal ultrasound and systematic sextant biopsy, including a quantitative assessment of cancer in the biopsies with organ confined tumor growth, was statistically evaluated. Except for serum PSA and PSA density preoperative characteristics were considered separately for each prostate lobe. Multivariate analysis results were validated prospectively in 353 patients.

RESULTS

On univariate analysis the number of positive biopsies was the most useful single parameter with a positive predictive value of 83% in 274 lobes and a negative predictive value of 55%, followed by mm. of tumor in the biopsy. Of all characteristics included in multivariate analysis only the number of biopsies with high grade cancer, the number of positive biopsies and serum PSA were independent for predicting organ confined cancer. When PSA was less than 10 ng./ml. and not more than 1 biopsy with high grade cancer was identified in a lobe, organ confined tumor growth was present in 86.1% of cases. On prospective validation the same criteria led to an 88.5% incidence of organ confined prostate cancer. Pooling the 2 most favorable groups led to 391 prostate lobes (70.8% of those investigated) with a positive predictive value of 82.1% (95% confidence interval 77.9% to 85.8%). Using the multivariate approach more prostate lobes were assigned to a favorable risk group than on univariate analysis. Clinical stage and simple Gleason grade did not contribute independent information for predicting organ confined disease.

CONCLUSIONS

Quantifying cancer and high grade cancer by systematic biopsy and serum PSA concentration are useful preoperative characteristics for predicting organ confined prostate cancer. Side specific analysis of these parameters is a flexible and reliable tool for selecting patients for nerve sparing radical prostatectomy.

[Mucinous adenocarcinoma of the urachus. Case report and review of the literature]

We report on a 44-year-old man with the rare case of a mucin-positive carcinoma of the urachus. We performed extended partial cystectomy with regional staging lymphadenectomy of the obturator lymph nodes. Histological investigation revealed a mucin-positive carcinoma of the urachus with negative lymph nodes. For this case, we present symptoms, a plan for diagnosis, and treatment of these tumors.

Analysis of molecular isoforms of PSA and their ratios in men with PSA-relapse after radical prostatectomy

BACKGROUND

The aim of this study was the longitudinal comparison of % f-PSA in patients before radical prostatectomy and after PSA relapse. Is % f-PSA a consistent tumor specific parameter or does this ratio change during untreated tumor progression?

MATERIALS AND METHODS

In this study 41 out of 420 patients with untreated increasing PSA-progression (> 0.5 ng/ml) were analysed. Patients with neoadjuvant or adjuvant hormonal therapy were excluded. T-PSA were f-PSA were analyzed by Immulite DPC (Diagnostic Products Coop., CA) and Abbott Axsym (Abbott Park, Il, USA).

RESULTS

Pre-operative % f-PSA ratio was 10.6% (range 4.6-22%; Std. dev.: 4.9); T-PSA concentration was 26.4 ng/ml (range 5.5-10.2 ng/ml Std. dev.: 20.3). In men with PSA relapse after radical prostatectomy % f-PSA ratio was 14.73% (range 2.2-4.5% Std. dev.: 9.7). Repeated post-operative % f-PSA measurements resulted in 12.94% f-PSA (range 2.7-3.8% Std. dev.: 9.9%) with a regression of R = 0.57. All men with pre-operative elevated % f-PSA (> 15%) had post-operative elevated % f-PSA.

CONCLUSIONS

The data indicates that post-operative % f-PSA is a constant tumor specific parameter in men with untreated PSA relapse after radical prostatectomy. Post-operative % f-PSA was higher compared with pre-operative % f-PSA concentrations. No correlation with Gleason score or pathological stage was found.

Stage migration in clinically localized prostate cancer

OBJECTIVES

To determine whether migration of pathological tumor stages in patients with clinically localized prostate cancer exists and whether this is due to an increasing frequency of treating patients with clinically insignificant cancer.

METHODS

1,063 radical retropubic prostatectomies were performed in patients with clinically localized prostate cancer in one institution within 7.5 years (from 1992 until June 1999). All specimens were prospectively processed according to the Stanford protocol. These were then analyzed regarding the migration of pathological tumor stages and cancer volumes.

RESULTS

Within the observation period, the annual rate of radical retropubic prostatectomies increased by 225% from 69 to 224 cases. The authors noted a decline of advanced tumor stages (from 65 to 40%) and an increase in pathological T2 tumors (from 30 to 55%). The rate of small cancers (<0.5 cm(3)) remained stable between 2 and 5% over the last 5 years.

CONCLUSION

The data confirm trends which were observed in large US centers with increasing detection and treatment of localized prostate cancer without unnecessary treatment of clinically insignificant cancers.

Human glandular kallikrein 2: a potential serum marker for predicting the organ confined versus non-organ confined growth of prostate cancer

PURPOSE

We measured serum levels of human glandular kallikrein 2 (hK2) in patients with prostate cancer treated with radical retropubic prostatectomy for clinically localized prostate cancer to determine whether preoperative hK2 levels discriminate stage pT2a/b from pathological stage T3a or greater cancer. This finding would help to predict preoperatively the organ confined versus non-organ confined growth of prostate cancer.

MATERIALS AND METHODS

A total of 68 consecutive men underwent radical retropubic prostatectomy for clinically localized prostate cancer. Serum was obtained 1 day preoperatively before prostatic manipulation. hK2, and total and free prostate specific antigen (PSA) were measured using immunofluorometric assays. Mean, median and range of hK2, total and free PSA, and the ratio of free-to-total PSA (percent free PSA) were calculated. Each analyte or combination of analytes was evaluated to determine whether it significantly contributed to enhance the discrimination of organ confined from non-organ confined cancer. We calculated the statistical significance of observed differences using the Mann-Whitney U and Kruskal-Wallis tests. Sensitivity and specificity calculations were performed for hK2, total PSA and the algorithm, (hK2) x (total PSA/free PSA) in addition to receiver operating characteristics curves and the respective areas under the curves. Multivariate logistic regression analysis was done for hK2, and total and free PSA RESULTS: Disease was organ and non-organ (extraprostatic extension) confined in 38 and 30 men, respectively. In organ confined cancer mean hK2 was significantly lower than in non-organ confined cancer (0.09 ng./ml., range less than 0.03 to 0.23 versus 0.30, range 0.04 to 0.94, p <0.0001). In addition, there was significantly higher free and total but not percent free PSA in non-organ than in organ confined cases. There were also statistically significant differences in hK2, free PSA and total PSA at each pathological disease stage (p <0.001, <0.01 and <0.05, respectively). Sensitivity for detecting organ confined disease was 37% at 100% specificity (correct identification of all non-organ confined cancer) using hK2 measurements compared with a sensitivity of 14% for total PSA. At a specificity of 95%, sensitivity was 40% for hK2 versus 23% for total PSA, which was a statistically significant gain in sensitivity (p <0.05). Receiver operating characteristics curves demonstrated that hK2 had the largest area under the curve, followed by the algorithm, (hK2) x (total PSA/free PSA), and total PSA (0.76, 0.75 and 0.72, respectively). However, none of area under the curve differences was statistically significant.

CONCLUSIONS

Compared with total and free PSA hK2 testing improved the preoperative evaluation of patients who underwent radical retropubic prostatectomy due to the superior discrimination of organ from non-organ confined cancer.

Super-sensitive prostate-specific antigen (PSA) in serum of women with benign breast disease or breast cancer

BACKGROUND

Serum prostate-specific antigen (PSA) can be discovered in patients with breast cancer. We used ultrasensitive methods of PSA detection, successfully developed for early detection of PSA recurrence in prostatic-cancer patients, to study PSA in women with breast cancer and benign breast lesions before and after surgery.

MATERIALS AND METHODS

Blood samples of 45 women with suspect breast findings were prospectively analyzed for PSA before and after breast surgery. Supersensitive 2nd and 3rd generation DPC assays were used to measure PSA (clinical detection limit of > 0.1 and > 0.02 ng/mL, respectively) and combined with concentration of serum to improve the clinical detection limit to > 0.025 and > 0.005 ng/mL, respectively. PSA concentrations were correlated with histological findings.

RESULTS

The most sensitive detection was required to detect PSA preoperatively in 12 out of 45 patients, 8 (31%) out of 26 breast-cancer patients and 4 (25%) out of 16 patients with benign breast lesions. Postoperatively, 13 out of 45 patients were positive for PSA, 7 (27%) breast-cancer patients and 6 (23%) patients with benign breast lesions.

CONCLUSIONS

Cancer patients showed the highest concentrations of PSA measured preoperatively and a decrease after surgery that was however not significant. Women with breast lesions expressed serum PSA in one third of the cases studied. PSA expression in serum does not distinguish benign from malignant breast diseases, but it might be valuable for follow-up to analyze whether recurrent disease can be detected with quantitative ultrasensitive PSA measurement.

[Prognostic markers for prostate cancer]

Careful consideration of therapy for prostate cancer needs an accurate analysis of prognostic markers to estimate success and benefit for the patient. Prognosis of prostate cancer is determined by the proportion of high grade cancer, many usually utilized prognostic characteristics were rejected by multivariate analysis as no independent prognostic information was delivered. For planning therapy it is crucial to estimate the proportion of high grade cancer as exact as possible. A standardized biopsy technique combined with a quantified analysis of the biopsy cores is most helpful to achieve this goal. The prognostic value of molecular biological and other factors is object of research, only a combination of some of these factors could be demonstrated so far to be superior to the estimation of the proportion of high grade cancer. However, at present their routine use in daily practise is precluded by a high technical and financial expense.

Significance and metabolism of complexed and noncomplexed prostate specific antigen forms, and human glandular kallikrein 2 in clinically localized prostate cancer before and after radical prostatectomy

PURPOSE

We studied plasma concentrations and elimination rates of prostate specific antigen (PSA) complexed to alpha1-antichymotrypsin and alpha2-macroglobulin, free PSA, total PSA (free PSA plus PSA alpha1-antichymotrypsin) and human glandular kallikrein 2 before, during and after radical retropubic prostatectomy for clinically localized prostate cancer.

MATERIALS AND METHODS

Plasma was collected and frozen within 10 minutes after sampling from 18 patients undergoing radical retropubic prostatectomy for prostate cancer. One sample was drawn preoperatively. Subsequent sampling intervals were 5 to 20 minutes perioperatively, 2 to 4 hours during the first 12 postoperative hours and 24 to 48 hours until postoperative day 14. Free PSA, PSA alpha1-antichymotrypsin, total PSA, PSA alpha2-macroglobulin and human glandular kallikrein 2 were measured with time resolved immunofluorometric assays.

RESULTS

Preoperatively PSA alpha2-macroglobulin was undetectable (less than 2 ng./ml.) in 17 of 18 patients. Human glandular kallikrein 2, free PSA and total PSA but not PSA alpha1-antichymotrypsin were significantly higher in patients with extraprostatic cancer (pT3a-pT4a, pN1) compared to those with organ confined cancer (pT2a/b). Surgical manipulation of the prostate caused no detectable elevation of human glandular kallikrein 2, PSA alpha1-antichymotrypsin or PSA alpha2-macroglobulin. In contrast, a mean 9.6-fold increase (range 3.4 to 22) in free PSA was noted 5 minutes after prostatectomy. Free PSA was eliminated from plasma in a biphasic exponential pattern with an early plasma half-life of 55 minutes and a late plasma half-life of 18 hours. PSA alpha1-antichymotrypsin decreased slowly, whereas human glandular kallikrein 2 was detectable only 12 hours after prostatectomy. PSA alpha2-macroglobulin remained at insignificant, nondetectable concentrations during the entire perioperative and postoperative period.

CONCLUSIONS

Release of free PSA contributes to the elevation of plasma total PSA after prostatectomy. Free PSA is enzymatically inactive as the release does not result in subsequent elevation of PSA alpha1-antichymotrypsin or PSA alpha2-macroglobulin. Biphasic exponential elimination of free PSA may be explained by rapid extracellular redistribution (early half-life) and glomerular filtration in the kidneys (late half-life). Our data suggest rapid metabolism of human glandular kallikrein 2 but do not support suggestions of the significance in vivo of complex formations with alpha2-macroglobulin as a major means to eliminate PSA from plasma in patients with clinically localized prostate cancer.

Supersensitive PSA-analysis after radical prostatectomy: a powerful tool to reduce the time gap between surgery and evidence of biochemical failure

BACKGROUND

Using three commercially available, unmodified PSA assays, 917 sera of 355 patients after radical prostatectomy underwent native and lyophilisation-concentrated PSA-detection to evaluate the benefit of serum concentration as a tool to increase sensitivity for earlier detection of recurrent prostate cancer after RP.

MATERIALS AND METHODS

We evaluated Abbott IMX, Tosoh ALA-600 and DPC-Immulite Assay in the follow-up of 355 patients. Mean follow-up time is 374 days (43-2057). All sera underwent native analysis and 4 fold- lyoconcentration and subsequent triplicate standard analysis on each assay. Evaluation of native and concentrated sera: A PSA-value of > or = 0.10 ng/ml was positive. Sera reading < 0.10 ng/ml were considered negative. In 4-fold concentrated sera this means a calculated increase of sensitivity to > or = 0.025 ng/ml. The average day of detection of a first positive signal either in native or concentrated sera for each assay was calculated as well as the time showing the average day difference of earlier detection in the lyoconcentrated sera for each assay. 20 Female sera were run and consistently read zero values in native and concentrated sera.

RESULTS

In 355 patients, the number of PSA-positive patients were 58, 65 and 62 on Abbott, Tosoh and Immulite, respectively. 17/58 (29.3%), 19/65 (29.2%) and 20/62 (31.7%) patients could be identified earlier in lyoconcentrated than in native sera. A mean time advantage of 308-336 days was found. No patient who was positive according to supersensitive criteria had a negative supersensitive result, in his later follow-up. 17/19 (89.4%) patients in the Tosoh, 17/20 (85%) in the Immulite and 10/17 (58.8%) in the Abbott were identified as PSA-positive within one year after RP.

CONCLUSION

PSA was positive in lyoconcentrated sera a mean of one year earlier than in native sera The maximum time advantage of lyoconcentration was 862 days, indicating PSA-recurrence 2.3 years earlier than standard analysis. 58.8-89.4% of patients with biochemical evidence of PSA-recurrence in supersensitive analysis were found within one year after RP. Lyoconcentration increases PSA-signals reliably in different assays. It can be performed as a quick routine procedure.