Use of systematic biopsy results to predict pathologic stage in patients with clinically localized prostate cancer: a preliminary report

Correlation between prostate needle biopsies and radical prostatectomy specimens: can we predict pathological outcome?

AIMS

Prostate needle biopsy findings provide important information when considering treatment options. We examine the correlation between needle biopsy and radical prostatectomy pathology to predict patients at high risk of harbouring adverse pathological findings.

METHODS

We reviewed data from 100 consecutive patients who underwent radical prostatectomy between 1 January 2003 and 31 January 2005 at the Singapore General Hospital. Pre-operative clinical findings and needle biopsy pathological data were prospectively collected and compared with the final histology.

RESULTS

The mean pre-biopsy PSA level was 9.4 +/- 5.1 microg/L. Median maximum percent of tumour in any core was 50% (range 5-100) and mean percentage of positive cores was 34.5 +/- 23%. There was under-grading of the final tumour score in 27 (27%) patients on biopsy as compared with the radical prostatectomy, while over-grading occurred in eight (8%) patients. On stratifying patients pre-operatively into low risk and high risk groups, patients in the high risk group had a significantly higher chance of having adverse radical prostatectomy histology such as extraprostatic extension, positive surgical margins or tumour volume >3.0 mL (p = 0.041, OR = 3.96, 95%CI 1.13-13.86).

CONCLUSIONS

Our results demonstrated good pathological correlation between prostate needle biopsies and their radical prostatectomies. Patients with Gleason scores of 7 or more, maximum percent of tumour in any core >50%, or percent of positive cores of >50% on needle biopsy had a higher risk of having adverse pathological findings at radical prostatectomy. The converse, however, is not necessarily true, as a result of sampling error during the biopsy.

Prediction of pathological stages before prostatectomy in prostate cancer patients: analysis of 12 systematic prostate needle biopsy specimens

OBJECTIVE

To identify the most reliable predictor of the pathological stage among multiple parameters obtained by performing systematic biopsies and to assess the predictive value of any identified parameters in combination with the prostate specific antigen and the Gleason scores.

METHODS

We examined 5 biopsy parameters from 12 systematic needle biopsy results in 104 consecutive prostate cancer patients who underwent prostatectomy: the number of cores positive for cancer, percentage of positive biopsy cores, total linear cancer length (absolute sum of tumor length at each core), percentage cancer length (total cancer length divided by total length of cores obtained x100), and maximum cancer core length. The predictive values of these parameters were assessed using multivariate logistic analysis and receiver operating characteristic analysis. We evaluated whether the most reliable biopsy parameter in combination with traditional variables show better predictability of the pathological stage than traditional variables alone by receiver operating characteristic analysis.

RESULTS

Of 104 patients, 85 (82.9%) had organ confined cancer and 19 (17.1%) showed extraprostatic extension. Of the five parameters examined, maximum cancer length was found to best predict pathological staging. Although insignificant, adding results of maximum cancer length to prostate specific antigen and Gleason scores improved predictability. Of 41 patients with a maximum cancer length of <0.9 cm, PSA of <16 ng/mL, and Gleason score of <7, none showed extraprostatic extension.

CONCLUSIONS

The maximum cancer length was found to be the most reliable predictor of disease staging. The findings of a maximum cancer length of <0.9 cm, PSA of <16 ng/mL, and a Gleason score of <7 can suggest an organ-confined disease.

Percentage of Cancer in Prostate Biopsies as Prognostic Factor for Staging and Postoperative Biochemical Failure after Radical Prostatectomy

OBJECTIVE

To assess if the percentage of cancer in prostate needle biopsies provides independent prognostic information for predicting pathological stage and/or biochemical relapse after radical prostatectomy.

METHODS

One hundred and forty prostate cancer patients who underwent radical prostatectomy were evaluated. Preoperative parameters analyzed were patient age, PSA, clinical stage, and the information obtained from sextant biopsies (Gleason score, maximum percentage of cancer in a core, percentage of tissue with cancer in all biopsies and the number of cores positive for cancer). Univariate and multivariate analyses (logistic regression) for the dependent variables (prostate cancer, organ-confined and biochemical relapse) were performed.

RESULTS

The tumor was organ-confined in 73.6% of patients. In those patients studied for disease progression (n = 126), no biochemical recurrence was observed in 76.2%. In the multivariate analysis for organ-confined disease, the total percentage of biopsy tissue with cancer, the preoperative PSA level, the Gleason score and the clinical stage were the most accurate predictive factors of pathological stage. The multivariate analysis for the study of biochemical failure indicated that only the total percentage of biopsy tissue with cancer, the preoperative PSA level and the Gleason score were independent predictive factors. According to the logistic regression analysis for disease recurrence, 3 risk groups could be identified: low risk (less than 10% probability of disease progression), intermediate risk (30%) and high risk (more than 70%).

CONCLUSIONS

The percentage of cancer in prostate biopsy provides independent prognostic information for predicting pathological stage and the risk of biochemical failure after radical prostatectomy.

Evaluation of a Contralateral Biopsy Specimen in Prostate Cancer Patients with Unilateral Suspicious Lesions

INTRODUCTION

In patients with a clinically unilateral palpable and/or visible lesion confined to the prostate on digital rectal examination and transrectal ultrasonography, the findings of biopsy specimens of a clinically unsuspicious lobe do not reflect TNM staging results (2002 classification). In patients with such a unilateral lesion, we compared the biopsy results of a clinically unsuspicious lobe with the pathological assessment of the radical prostatectomy specimen and evaluated the importance of the results of biopsy specimens in an unsuspicious lobe.

PATIENTS AND METHODS

Between April 2000 and August 2004, 97 prostatic cancer patients without neoadjuvant therapy underwent a radical retropubic prostatectomy. In the patients with a unilateral lesion on digital rectal examination and/or transrectal ultrasound, the preoperative prostate-specific antigen levels, the results of contralateral biopsy specimens, and contralateral cancer foci in radical prostatectomy specimens were examined.

RESULTS

Of 39 patients with a unilateral palpable and/or visible lesion, 15 had contralateral positive biopsy findings, while 24 had contralateral negative biopsy findings. In a pathological analysis of prostatectomy specimens, a significantly higher rate of clinically significant cancer foci and a larger cancer volume in a clinically unsuspicious lobe have been observed in patients with contralateral positive biopsy findings than in patients with contralateral negative biopsy findings (p < 0.001). Moreover, contralateral cancer foci in patients with a contralateral positive biopsy specimen exhibited a more ominous state, such as seminal vesicle invasion, extraprostatic extension, and a positive surgical margin, than those in patients with a contralateral negative biopsy specimen (40.0 vs. 8.3%, p = 0.017). However, in a pathological analysis of both ipsilateral and contralateral cancer foci, the proportion of ominous pathological findings did not differ between the patients with a contralateral positive biopsy and those with a contralateral negative biopsy.

CONCLUSIONS

In patients with clinically unilateral palpable and/or visible tumors confined to the prostate, the results of a bilateral biopsy need not be used to determine the clinical stage. However, in patients with positive biopsy results for an unsuspicious lobe, urologists should perform an extended surgical resection.

Active Surveillance for Prostate Cancer: For Whom?

Prostate-specific antigen (PSA) –based prostate cancer screening results in the diagnosis of prostate cancer in many men who are not destined to have clinical progression during their lifetime. Good-risk prostate cancer, defined as a Gleason score of 6 or less, PSA < 10, and T1c to T2a, now constitutes 50% of newly diagnosed prostate cancer. In most of these patients, the disease is indolent and slow growing. The challenge is to identify those patients who are unlikely to experience significant progression while offering radical therapy to those who are at risk. The approach to favorable-risk prostate cancer described in this article uses estimation of PSA doubling time (PSA DT) to stratify patients according to the risk of progression. Patients who select this approach are managed initially with active surveillance. Those who have a PSA DT of 3 years or less (based on a minimum of three determinations over 6 months) are offered radical intervention. The remainder are closely monitored with serial PSA and periodic prostate rebiopsies (at 2, 5, and 10 years). In this series of 299 patients, the median DT was 7 years. Forty-two percent had a PSA DT > 10 years, and 20% had a PSA DT > 100 years. The majority of patients on this study remain under surveillance. The approach of active surveillance with selective delayed intervention based on PSA DT represents a practical compromise between radical therapy for all (which results in overtreatment for patients with indolent disease) and watchful waiting with palliative therapy only (which results in undertreatment for those with aggressive disease).

Validation of criteria used to predict extraprostatic cancer extension: a tool for use in selecting patients for nerve sparing radical prostatectomy

PURPOSE

We have previously reported that a prostate biopsy core specimen with a tumor length of at least 7 mm plus any positive basal biopsy core is the best predictor of extraprostatic extension (EPE) in radical prostatectomy (RP) specimens. We present prospectively collected data to validate our results.

MATERIALS AND METHODS

The study included 270 patients who underwent RP for localized prostate cancer between January 2002 and December 2003 by a single surgeon. We correlated side specific biopsy data, pretreatment prostate specific antigen, clinical stage and RP type using pathological specimen data.

RESULTS

Mean patient age was 59.6 years and median prostate specific antigen was 8.24 ng/ml. Of the patients 94 (35%) underwent unilateral and 114 (42%) underwent bilateral nerve sparing RP. The overall incidence of EPE was 16%. The incidence of EPE was 33% in patients who met our criteria vs 4.6% in those who did not. Of 538 evaluable sides 7.2% were positive at the surgical margin. The incidence of ipsilateral positive margins was 2.5% when the neurovascular bundle was spared according to our criteria vs 11.8% when the bundle was resected according to criteria.

CONCLUSIONS

This series validates our finding that a prostate biopsy core with a tumor length of at least 7 mm plus a positive basal biopsy core of any length and tumor grade is predictive of ipsilateral EPE. In the absence of these criteria the incidence of ipsilateral positive margins is low. Thus, these criteria are valuable for predicting EPE and selecting patients for nerve sparing RP.

Tumor length and location of cancer on biopsy predict for side specific extraprostatic cancer extension

PURPOSE

We studied preoperative variables in a contemporary series of men who underwent nonnerve sparing radical prostatectomy in an effort to establish criteria that would predict side specific extraprostatic extension (EPE) of cancer.

MATERIALS AND METHODS

We reviewed the records of 430 patients who underwent radical prostatectomy for localized prostate cancer with no prior therapy between 1996 and 1998, and for whom we had at least sextant biopsy information. We evaluated biopsy data (Gleason score, maximum length of cancer in positive cores, percent of cancer per involved core, proportion of positive biopsy cores, tumor location and number of positive biopsy cores) and correlated these findings with EPE at the neurovascular bundle and posterior lateral (NVB/PL) region.

RESULTS

We found that a higher number of positive cores, a higher biopsy Gleason score on a side, a positive core at the basal region, 50% or greater tumor in the core or a maximum tumor length of 7 mm or greater increased the likelihood that EPE was present at the NVB/PL region on the corresponding side of the prostate. On multivariate analysis maximum tumor length 7 mm or greater and positive basal core location were the strongest independent predictors of EPE at the NVB/PL region on a given side (p <0.0001 and 0.002, respectively).

CONCLUSIONS

Excluding any patient with 1 positive biopsy core with a maximum tumor length of 7 mm or greater plus a positive basal core of any tumor length and grade can decrease the risk of EPE at the NVB/PL region to approximately 10%.

Does the adjunct of ecographic contrast medium Levovist improve the detection rate of prostate cancer?

OBJECTIVES

To evaluate whether the adjunct of an ultrasound contrast medium improves the detection rate of prostate cancer.

METHOD

In 34 patients, scheduled to undergo a trans-perineal extended prostate biopsy, we carried out a color-Doppler ultrasound (CDU) of the prostate before and after i.v. injection of Levovist, an ultrasound contrast medium. Further bioptic samples were taken in the areas where a marked increase in vascularization was noticed.

RESULTS

The overall diagnostic sensitivity, specificity and efficiency were respectively 72.7, 56.2 and 62.9% for transrectal ultrasound (TRUS); 80, 56.2 and 65.3% for CDU and 88.8, 54.5 and 68% for CDU after Levovist injection; 66.5, 72.6 and 65.1% for digito-rectal examination (DRE); 100, 51.4 and 65.4% for total PSA; and 100, 88.8 and 94.3% for PSA free/total. In the 16 patients with prostate carcinoma, the sensitivity of CDU after Levovist was 92.3, 66% for both DRE and TRUS, and 80% for DRE plus TRUS.

CONCLUSIONS

Considering the cost and the results obtained (high sensitivity and low specificity), a routine use of Levovist does not seem indicated in patients undergoing prostatic biopsy. An exception may be represented by patients with both negative DRE and TRUS.

Six additional systematic lateral cores enhance sextant biopsy prediction of pathological features at radical prostatectomy

PURPOSE

We evaluated the contribution of 6 additional systematically obtained, laterally directed biopsy cores to traditional sextant biopsy for the prediction of final pathological findings in the radical prostatectomy specimen.

MATERIALS AND METHODS

We studied 178 consecutive patients with no history of prostate biopsy in whom prostate cancer was diagnosed during an initial systematic 12 core biopsy and who subsequently underwent radical prostatectomy. Of the systematic 12 cores we compared the subset of the 6 traditional sextant cores (S6C), the set of 6 laterally directed cores (L6C) and the complete 12 core set, which included the 6 traditional sextant and the 6 laterally directed cores. Biopsy Gleason score, number of positive cores, total cancer length and percent of tumor in the biopsy sets were examined for their ability to predict extracapsular extension, total tumor volume and pathological Gleason score.

RESULTS

On univariable analyses the biopsy parameters of the complete 12 core set correlated more strongly with extracapsular extension and total tumor volume than the biopsy parameters of S6C or L6C. On multivariable analyses S6C and L6C were independent predictors of pathological features at prostatectomy.

CONCLUSIONS

The addition of 6 systematically obtained, laterally directed cores to traditional sextant biopsy improved the ability to predict pathological features at prostatectomy by a statistically and prognostically significant margin. Preoperative nomograms that use data from a full complement of 12 systematic cores, specifying sextant and laterally directed biopsy cores, should demonstrate improved performance in predicting prostatectomy pathology.

Preoperative Prediction of Pathological Stage by Quantitative Histology in 102 Patients with Prostate Cancer (PCa) and Serum PSA ≤10 ng/mL

Purpose. To find a predictor of extraprostatic extension in clinically localized prostate cancer (PCa), preoperative ultrasound-guided prostate needle biopsies and clinicopathological data were reviewed.

Materials and Methods

102 consecutive patients (median age 63 years) with serum PSA ≤10 ng/mL who underwent radical retropubic prostatectomy were included. Preoperative prostate biopsies according to an extended protocol were performed and whole-mount prostatectomy specimens were processed. One or more of the following biopsy variables were considered predictive of locally andvanced PCa: more than 2/12 cancer-positive cores, total percentage of cancer (TPC) >20%, greatest percentage of cancer (GPC) >50%, bilateral PCa, presence of cancer in both lateral portions, Gleason score >6.

Results

Only 32/102 (31.4%) specimens showed an organ-confined PCa; the remaining were pT3a in 30 (29.4%) cases, pT3b in 6 (5.9%) and pT2–T3 with positive surgical margins in 34 (33.3%). Quantitative histology predicted an organ-confined PCa in 41.2% of patients. In all 102 patients and in 56 with T1c clinical stage, the positive predictive value (PPV) and negative predictive value (NPV) of biopsy findings, to predict an organ confined PCa, was 81.2 vs 92% and 91.6 vs 93.4%, respectively. The PPV and NPV to predict a locally advanced PCa was 92.8 and 86.5%, respectively.

Conclusions

Quantitative histology seems to be helpful for locally staging of PCa in patients with T1c clinical stage and PSA ≤10 ng/mL.

Assessment of the Enhancement in Predictive Accuracy Provided by Systematic Biopsy in Predicting Outcome for Clinically Localized Prostate Cancer

PURPOSE

Current localized prostate cancer treatment outcome nomograms rely on prostate specific antigen (PSA), tumor stage and grade. We investigated whether the addition of prostate biopsy features may enhance the accuracy of a nomogram predicting recurrence after radical prostatectomy (RP).

MATERIALS AND METHODS

Clinical data from 1,152 patients who underwent RP were used and included PSA, clinical stage, biopsy Gleason grade and systematic biopsy information that quantified the amount of cancer and high grade cancer. Predictive accuracy for freedom from recurrence after RP was assessed with and without tumor quantification in the biopsy by the area under the receiver operating characteristics curve (AUC).

RESULTS

Percentage and number of cores with cancer, and percentage and number of cores with high grade cancer were predictors of outcome when added to models that included PSA, Gleason grade and clinical stage (all p <0.0001). Nomogram accuracy with 3 traditional variables (AUC 0.790) was minimally enhanced with the addition of percentage or number of positive cores (AUC 0.804 and 0.800, respectively), or percentage or number of cores with high grade cancer (AUC 0.802 and 0.800, respectively). Maximum predictive accuracy of 0.811 was achieved after supplementing the traditional 3-variable nomogram with various combinations of additional pathological predictors.

CONCLUSIONS

The information provided by systematic biopsies substantially improves the ability to predict outcome following RP. However, some incremental predictive accuracy was achieved by adding systematic biopsy features.

Decision making using hybrid rough sets and neural networks

A methodology for using rough sets theory for preference modeling in decision problem is presented in this paper. We will introduce a new method where neural network systems and rough sets theory are completely integrated into a hybrid system and are used cooperatively for decision and classification support. At the first glance, the two methods we discuss have not much in common. But, in spite of the differences between them, it is interesting to try to incorporate both into one combined system, and apply it in the building of a decision support system.

Pathologic evidence of dose-response and dose-volume relationships for prostate cancer treated with combined external beam radiotherapy and high-dose-rate brachytherapy

PURPOSE

The clinical significance of postradiotherapy (RT) prostate biopsy characteristics is not well understood relative to the known prognostic factors. We performed a detailed pathologic review of posttreatment biopsy specimens in an attempt to clarify their relationship with clinical outcome and radiation dose.

METHODS AND MATERIALS

Between 1991 and 1998, 78 patients with locally advanced prostate cancer were prospectively treated with external beam RT in combination with high-dose-rate brachytherapy at William Beaumont Hospital and had post-RT biopsy material available for a complete pathologic review. Patients with any of the following characteristics were eligible for study entry: pretreatment prostate-specific antigen level > or =10.0 ng/mL, Gleason score > or =7, or clinical Stage T2b-T3cN0M0. Pelvic external beam RT (46.0 Gy) was supplemented with three (1991-1995) or two (1995-1998) ultrasound-guided transperineal interstitial (192)Ir high-dose-rate implants. The brachytherapy dose was escalated from 5.50 to 10.50 Gy per implant. Post-RT prostate biopsies were performed per protocol at a median interval of 1.5 years after RT. All pre- and post-RT biopsy specimen slides from each case were reviewed by a single pathologist (N.S.G.). The presence and amount of residual cancer, most common RT-effect score, and least amount RT-effect score were analyzed. The median follow-up was 5.7 years. Biochemical failure was defined as three consecutive prostate-specific antigen rises.

RESULTS

Forty patients (51%) had residual cancer in the post-RT biopsies. The 7-year biochemical control rate was 79% for patients with negative biopsies vs. 62% for those with positive biopsies with marked RT damage vs. 33% for those with positive biopsies with no or minimal RT damage. A greater percentage of positive pre-RT biopsy cores (p = 0.01), lower total RT dose (p = 0.001), lower dose per implant (p = 0.001), and greater percentage of positive post-RT biopsy cores (p = 0.01) were each associated with biochemical failure (Cox regression, univariate analysis). For patients with <25% positive post-RT biopsy cores, the 7-year biochemical control rate was 81% vs. a 62% biochemical control rate for those with 25-49% positive cores and only 32% for those with > or =50% positive cores (p = 0.01). On Cox multiple regression analysis, only the percentage of positive pre-RT biopsy cores and RT dose remained significantly associated with biochemical failure. Of all the factors analyzed, only the pretreatment cancer volume and lower RT dose were significantly associated with residual cancer and/or residual cancer with no or minimal RT damage. A greater percentage of positive pre-RT biopsy cores was associated with both a positive post-RT biopsy (p = 0.08) and a greater percentage of positive post-RT biopsy cores (p = 0.04). A lower total RT dose was associated with both a positive post-RT biopsy (p = 0.08) and a greater percentage of positive post-RT biopsy cores (p = 0.02). For patients who received <80 Gy (equivalent in 2-Gy fractions), 73% had positive post-RT biopsies vs. a 56% biopsy positivity rate for those who received 84-90 Gy and only 39% for those who received > or =92 Gy (p = 0.07).

CONCLUSION

Patients with positive post-RT biopsies are more likely to experience biochemical failure, especially when the RT damage is minimal. Patients who have a larger pretreatment tumor volume or receive a lower RT dose are more likely to demonstrate post-RT biopsy positivity and biochemical failure.

Extraprostatic spread of clinically localized prostate cancer: factors predictive of pT3 tumor and of positive endorectal MR imaging examination results

PURPOSE

To identify the factor(s) most predictive of pT3 tumor and those most predictive of a positive endorectal magnetic resonance (MR) imaging result in patients with clinically localized prostate cancer.

MATERIALS AND METHODS

At multivariate analysis, five preoperative clinical parameters-prostate-specific antigen (PSA) level, digital rectal examination (DRE) result, Gleason score and number of involved sextants at transrectal US-guided biopsy, and endorectal MR imaging result-were used to predict pT3 tumor in 336 patients who underwent radical prostatectomy. On the basis of results of the first four examinations, multivariate analysis was performed also to determine predictors of a positive MR imaging study.

RESULTS

Significant predictors of pT3 tumor were positive MR imaging result (P < 2 x 10(-8)), more than one sextant involved at biopsy (P < 5 x 10(-5)), and PSA level greater than 10 ng/mL (P < 7 x 10(-3)). Significant predictors of a positive MR imaging result were three or more sextants involved at biopsy (P < 10(-5)), positive DRE result (P < 5 x 10(-3)), and PSA level greater than 10 ng/mL (P < 16 x 10(-3)). In the subgroup of 175 patients who had at least three positive biopsy specimens, the sensitivity of MR imaging was 50% for detection of occult pT3 tumor and 69% for detection of extensive pT3 tumor. The overall specificity of MR imaging was 95%.

CONCLUSION

Endorectal MR imaging seems to be indicated in carefully selected patients-specifically, those with three or more positive biopsy specimens, a palpable tumor, and/or a PSA level greater than 10 ng/mL.

Percent of cancer in the biopsy set predicts pathological findings after prostatectomy

PURPOSE

The ability to use pretreatment variables to identify patients with organ confined prostate cancer continues to challenge physicians. We examined information available preoperatively, including prostate needle biopsy, clinical stage and preoperative prostate specific antigen (PSA), and evaluated these data based on pathological variables after radical retropubic prostatectomy.

MATERIALS AND METHODS

We reviewed results in 135 consecutive patients who underwent radical retropubic prostatectomy at a single institution. Needle biopsy information, such as the number of cores, percent of tumor per biopsy set, laterality of positive cores and Gleason sum, were compared with pathological data on the radical retropubic prostatectomy specimen, including pathological stage, Gleason sum and tumor volume. Clinical data, including biopsy information and pathological findings, were compared using univariate and multivariate models.

RESULTS

Overall total PSA, percent of tumor in the biopsy and bilateral positive cores directly correlated with tumor volume (p <0.01). Also, increasing PSA, increasing percent of tumor in the biopsy and bilateral positive cores were associated with increased risks of extracapsular extension (p <0.01).

CONCLUSIONS

From the information readily available from prostate needle biopsy these results suggest that percent of tumor in the biopsy is a useful predictor of pathological stage and tumor volume. Furthermore, including percent of tumor in the biopsy set and bilateral disease with traditional variables such as serum PSA and clinical stage may improve pretreatment tumor staging. This finding adds additional credence to the inclusion of percent of tumor in the biopsy set in models for the preoperative prediction of pathological stage and should be factored into discussions with patients on treatment options.

Prospective validation of an algorithm with systematic sextant biopsy to predict pelvic lymph node metastasis in patients with clinically localized prostatic carcinoma

PURPOSE

We prospectively validate an algorithm to predict pelvic lymph node metastasis in patients with clinically localized prostatic carcinoma.

MATERIAL AND METHODS

A total of 293 patients with prostatic cancer were identified before pelvic lymph node dissection according to an algorithm developed with the classification and regression tree analysis as high-greater than 3 sextant biopsies containing any Gleason grade 4 or 5 cancer, intermediate-at least 1 biopsy dominated by Gleason grade 4 or 5 cancer but not high risk and low risk-all other patients. Observed and predicted frequencies of pelvic lymph node metastasis were compared.

RESULTS

The observed frequencies of lymph node metastasis were remarkably similar to the predicted frequencies, including 2.8% versus 2.2% in 85.7% of patients in the low risk group, 16.7% versus 19.4% in 10.2% intermediate and 41.7% versus 45.5% in 4.1% high, respectively. If patients in the low risk group were considered to have node negative disease the specificity and negative predictive value of the algorithm were 88.4% and 97.2%, respectively.

CONCLUSIONS

Our algorithm is valid as a simple and accurate tool for the prediction of pelvic lymph node metastasis in patients with clinically localized prostatic cancer. Those 85.7% of patients classified by the algorithm to have a low risk of lymphatic spread should not undergo pelvic lymph node dissection before definitive local treatment.

Prediction of tumour volume and pathological stage in radical prostatectomy specimens is not improved by taking more prostate needle-biopsy cores

OBJECTIVE

To determine what, if any, additional prognostic information is available from the prostate needle biopsy by comparing the number of biopsy cores obtained with the pathology assessed from the radical retropubic prostatectomy (RRP) specimen.

PATIENTS AND METHODS

The results from 135 consecutive patients who underwent RRP at a single institution were reviewed. Needle biopsy information (number of cores, percentage of positive cores, laterality of the positive cores, and Gleason sum) were compared with the pathological data of the RRP specimen, including stage, Gleason sum and tumour volume. Patients were further stratified into those with six or fewer cores (96 men) or more than six cores (39 men). Clinical data, including biopsy information and pathological findings, were compared using univariate and multivariate models.

RESULTS

Overall, univariate analysis showed that the total prostate-specific antigen (PSA) level, number of positive cores, bilateral positive cores and percentage of positive cores were directly correlated with tumour volume (P=0.01). Also, PSA and percentage of positive cores were directly correlated with extracapsular extension (P=0.008 and P=0.01, respectively). In the multivariate model, the most important independent predictors of RRP tumour volume and pathological stage were the preoperative PSA level and percentage of cancer in the biopsy (P<0.01). There was no significant relationship between the number of cores obtained and the predicted pathology of the RRP specimen. There were no differences in the number of positive cores, bilateral positive cores or percentage tumour in the cores between men with more or less than six biopsies. In men with more than six core biopsies, there was no significant increase in prognostic information for tumour volume and extracapsular extension, or a correlation between the Gleason sum on biopsy and the RRP specimen. Taking more than six biopsies did not result in a significantly greater detection of potentially indolent tumours (defined as a tumour volume of <0.5 mL).

CONCLUSIONS

While taking more prostate needle biopsy cores seems to improve the detection of prostate cancer, there appears to be no major improvement in prognostic information over that gained from traditional sextant biopsies. Furthermore, the results suggest that the percentage of positive cores is the best predictor of both pathological stage and tumour volume, from among the information readily available from prostate needle biopsy. Given the variability in the number of cores obtained for diagnosis in clinical practice, these results add credence to the use of the percentage of positive cores in the biopsy set, with known predictors such as PSA and Gleason score, into future models that attempt to predict tumour biology.

Ultrasound for prostate imaging and biopsy

Transrectal ultrasound guided systemic sextant needle biopsy of the prostate has been the procedure of choice for the diagnosis of prostate cancer. Several shortcomings of this procedure have been recognized and there is concern that it may represent an inadequate sampling of the prostate. Refinements include modifications of biopsy location and an increase in the number of cores obtained. Enhanced ultrasound techniques may improve the accuracy of prostate biopsy. In addition, research continues to develop prognostic factors derived from the core biopsy that may enhance the prediction of tumor biology. This paper provides a basic review of transrectal ultrasound diagnosis of prostate cancer with emphasis on advances in this area.

Indications and contraindications for nerve-sparing radical prostatectomy

Nerve-sparing radical prostatectomy can be performed safely in most men undergoing radical prostatectomy. As is true in many aspects of prostate cancer diagnosis and therapy, the key element is patient selection. With many prostate tumors diagnosed at an earlier stage, the authors have seen a shift toward more favorable pathologic findings at the time of surgery. Concomitant with the success of early detection of prostate cancer is the realization that men are younger at the time of diagnosis and more interested in preserving sexual function. This article has described factors associated with an increased risk for extraprostatic tumor and, subsequently, an increased possibility of postprostatectomy cancer recurrence. Except for the previously mentioned absolute contraindications, none of these factors, by themselves, should be used to exclude a patient from nerve-sparing prostatectomy. Instead, meticulous attention must be given to the surgical dissection. If any doubt remains regarding residual tumor, the surgeon should err on the side of caution and remove the neurovascular bundle. The use of standardized intraoperative frozen-section analysis can help guide these decisions. The patient must be informed before surgery regarding the risks of nerve-sparing surgery, the potency rates of the surgeon, and the possibility that, to ensure adequate cancer control, the nerves may be sacrificed despite any preoperative optimism favoring the potential for their salvage.

Indicators of pathologic stage of prostate cancer and their use in clinical practice

Pathologic stage is the most reliable means of predicting the likelihood of curable prostate cancer at the time of definitive treatment. Its prediction is of the greatest importance to individuals with clinically localized disease, principally because of the therapeutic and prognostic implications. Multivariate models integrating variables that can be derived from clinical and pathologic assessment have been shown to be reliable and useful in urologic practice. Among these variables, the combination of clinical stage, serum PSA, and biopsy Gleason score provides reliable assessment of the risk for extraprostatic disease that can be used readily for counseling individual patients. Other biopsy-derived parameters may contribute additional information, but their value in multivariate analysis has not been validated in a multi-institutional setting. The development of new prognostic markers is a priority objective in current research to distinguish patients in whom cancer cannot be controlled by surgical treatment. For patients undergoing radical prostatectomy, definitive pathologic stage certainly will remain an important prognostic factor; therefore, clinical practice will continue to be determined by its accurate prediction.

[Percentage of tumor in prostatic biopsy cylinders as prognosis factor of organ-limited disease in candidates for radical prostatectomy]

The present study analyzes the prognostic influence of tumor percentage in cylinders of prostatic biopsy in this patient group.

MATERIAL AND METHODS

Retrospective study of 68 patients with a diagnosis of adenocarcinoma, clinical stage T1-T2 who had undergone a radical prostatectomy from May 1997 to october 2000. Following preoperative parameters were analyzed: age, PSA, clinical staging, Gleason and six cylinders of ultrasonography-leaded transrectal prostatic biopsy, studying the amount of positive biopsies, the tumor percentage of the total amount of biopsies and the maximum percentage of tumor in one cylinder. Univariate (square-Chi, Student t) and multivariate (multiple logistic regression) analysis are performed in order to study the relationship of these parameters with the presence or not of an organ-located disease.

RESULTS

An organ-located disease was shown at 44 patients through the piece of radical prostatectomy. The univariate analysis gave all studied parameters, except age, a prognostic value of the existence or not of an organ-located disease. In the multivariate analysis only the total percentage of biopsy tumors (p = 0.0002) and PSA (p = 0.005) behaved as independent prognostic factors.

CONCLUSION

Tumor percentage in prostatic biopsy seems to be a factor with a high predictive value of an organ-located disease, possibly because it is an index of tumoral volume.

Predicting prostate carcinoma volume and stage at radical prostatectomy by assessing needle biopsy specimens for percent surface area and cores positive for carcinoma, perineural invasion, Gleason score, DNA ploidy and proliferation, and preoperative serum prostate specific antigen: a report of 454 cases

BACKGROUND

DNA ploidy analysis of prostate carcinoma is a generally accepted prognostic marker, particularly when tumors are extraprostatic at the time of surgery. In the past decade, the DNA content of prostate carcinoma frequently has been assessed in needle biopsy specimens based on the assumption that ploidy, in conjunction with serum prostate specific antigen (PSA) and Gleason score, provides valuable pretreatment information.

METHODS

Between 1995 and 1998, the authors identified a consecutive series of 454 prostate carcinomas, verified by needle biopsies and followed by radical retropubic prostatectomies (RRP). Based on the needle biopsies, DNA ploidy and MIB-I immunostaining were measured by digital image analysis (DIA). The authors also quantified the percent of nuclei in four categories from the DNA histograms. The DIA data were combined with the age of the patient at diagnosis, the serum PSA, Gleason score, percent cores and percent surface area positive for carcinoma, and status of perineural invasion in multivariate models using tumor volume and risk of extraprostatic extension (EPE) at RRP as the outcome variables.

RESULTS

Joint predictors of tumor volume at RRP were the percent cores positive for carcinoma (P < 0.0001), serum PSA (P < 0.0001), the percent surface area positive for carcinoma (P < 0.0001), and the percent nuclei classified by DNA quantification to be in the "S-phase" category (P = 0.03). Joint predictors of risk of EPE were the percent cores positive for carcinoma (P = 0.0004), a Gleason score of 7 (P < 0.0001), a Gleason score of 8 or 9 (P < 0.0001), serum PSA (P = 0.006) and perineural invasion (P = 0.02).

CONCLUSIONS

After adjusting for traditional prognostic markers, DNA ploidy interpretation and MIB-I quantitation of prostate carcinoma did not appear to jointly predict either outcome variable in the multivariate models. However, a quantitative measure related to both ploidy and proliferation, the percent of nuclei in the putative "S-phase" category from the DIA histograms, was found to jointly predict for tumor volume.

Matched-pair analysis of conformal high-dose-rate brachytherapy boost versus external-beam radiation therapy alone for locally advanced prostate cancer

PURPOSE

We performed a matched-pair analysis to compare our institution's experience in treating locally advanced prostate cancer with external-beam radiation therapy (EBRT) alone to EBRT in combination with conformal interstitial high-dose-rate (HDR) brachytherapy boosts (EBRT + HDR).

MATERIALS AND METHODS

From 1991 to 1998, 161 patients with locally advanced prostate cancer were prospectively treated with EBRT + HDR at William Beaumont Hospital, Royal Oak, Michigan. Patients with any of the following characteristics were eligible for study entry: pretreatment prostate-specific antigen (PSA) level of >/= 10.0 ng/mL, Gleason score >/= 7, or clinical stage T2b to T3c. Pelvic EBRT (46.0 Gy) was supplemented with three (1991 through 1995) or two (1995 through 1998) ultrasound-guided transperineal interstitial iridium-192 HDR implants. The brachytherapy dose was escalated from 5.50 to 10.50 Gy per implant. Each of the 161 EBRT + HDR patients was randomly matched with a unique EBRT-alone patient. Patients were matched according to PSA level, Gleason score, T stage, and follow-up duration. The median PSA follow-up was 2.5 years for both EBRT + HDR and EBRT alone.

RESULTS

EBRT + HDR patients demonstrated significantly lower PSA nadir levels (median, 0.4 ng/mL) compared with those receiving EBRT alone (median, 1.1 ng/mL). The 5-year biochemical control rates for EBRT + HDR versus EBRT-alone patients were 67% versus 44%, respectively (P <.001). On multivariate analyses, pretreatment PSA, Gleason score, T stage, and the use of EBRT alone were significantly associated with biochemical failure. Those patients in both treatment groups who experienced biochemical failure had a lower 5-year cause-specific survival rate than patients who were biochemically controlled (84% v 100%; P <.001).

CONCLUSION

Locally advanced prostate cancer patients treated with EBRT + HDR demonstrate improved biochemical control compared with those who are treated with conventional doses of EBRT alone.