Prediction of prostate cancer volume using prostate-specific antigen levels, transrectal ultrasound, and systematic sextant biopsies

Is tumour volume an independent predictor of outcome after radical prostatectomy for high-risk prostate cancer?

BACKGROUND

Preoperative PSA, ISUP grade group (GG), prostate examination and multiparametric MRI (mpMRI) form the basis of prostate cancer staging. Unlike other solid organ tumours, tumour volume (TV) is not routinely used aside from crude estimates such as maximum cancer core length. The aim of this study is to assess the role of TV as a marker for oncological outcomes in high-risk non-metastatic prostate cancer.

METHODS

A prospectively maintained database of patients undergoing minimally invasive (laparoscopic or robot-assisted laparoscopic) radical prostatectomy at a UK centre between 2007 and 2019 were analysed. A total of 251 patients with NCCN high or very high-risk prostate cancer were identified. Primary outcome measure was time to biochemical recurrence (BCR) and the secondary outcome was time to treatment failure (TTF). TV was measured on the pathological specimen using the stacking method. Multivariable cox regression analysis was used to identify factors predicting BCR and TFF. TV as a predictor of BCR and TFF was further analysed through time-dependent receiver operating characteristic (ROC) curves. Kaplan-Meier survival estimates were used to evaluate TV cut-off scores.

RESULTS

Median follow up was 4.50 years. Four factors were associated with BCR and TFF on multivariable analysis (TV, pathological GG, pathological T stage, positive margin >3 mm). Area under the Curve (AUC) for TV as a predictor of BCR and TTF at 5 years was 0.71 and 0.75, respectively. Including all 4 variables in the model increased AUC to 0.84 and 0.85 for BCR and TFF. A 2.50 cm TV cut off demonstrated a significance difference in time to BCR, p < 0.001.

CONCLUSIONS

Pathological tumour volume is an independent predictor of oncological outcomes in high risk prostate cancer but does not add significant prognostic value when combined with established variables. However, the option of accurate TV measurement on mpMRI raises the possibility of using TV as useful marker for preoperative risk stratification.

Intraprostatic targeting

PURPOSE OF REVIEW

The ability to accurately localize and target prostate cancer, whether for staging or future interventions, is an important concept in prostate cancer management. In this review, we describe the emerging technologies that allow for enhanced visualization and precise targeting of the prostate cancer.

RECENT FINDINGS

Uses of prostate-specific antigen and conventional prostate biopsy with image-blinded random systematic techniques have led to overdiagnosis of insignificant cancer and underdiagnosis of significant cancer. Active surveillance and focal therapy have become hot topics in prostate cancer management as the incidence of low-risk prostate cancer rises. For either management, it is essential to localize, characterize, and target the clinically important cancer in the prostate. Emerging techniques in ultrasound as well as MRI modalities allow for enhancement of tumor visualization, and characterization. Digital mapping technique of biopsy trajectory is an emerging technique that allows for three-dimensional mapping of biopsy-proven cancer lesions as well as potential future delivery of focal therapy. Molecular or cancer-specific targeting is promising for specific imaging and therapeutic approach at the cell level.

SUMMARY

Emerging technologies improve clinically relevant prostate cancer identification using digitalized multiparametric anatomical and functional imaging and enhance the ability to precisely target the known-cancer.

The contemporary concept of significant versus insignificant prostate cancer

CONTEXT

The notion of insignificant prostate cancer (Ins-PCa) has progressively emerged in the past two decades. The clinical relevance of such a definition was based on the fact that low-grade, small-volume, and organ-confined prostate cancer (PCa) may be indolent and unlikely to progress to biologic significance in the absence of treatment.

OBJECTIVE

To review the definition of Ins-PCa, its incidence, and the clinical impact of Ins-PCa on the contemporary management of PCa.

EVIDENCE ACQUISITION

A review of the literature was performed using the Medline, Scopus, and Web of Science databases with no restriction on language up to September 2010. The literature search used the following terms: insignificant, indolent, minute, microfocal, minimal, low volume, low risk, and prostate cancer.

EVIDENCE SYNTHESIS

The most commonly used criteria to define Ins-PCa are based on the pathologic assessment of the radical prostatectomy specimen: (1) Gleason score ≤ 6 without Gleason pattern 4 or 5, (2) organ-confined disease, and (3) tumour volume<0.5 cm(3). Several preoperative criteria and prognostication tools for predicting Ins-PCa have been suggested. Nomograms are best placed to estimate the risk of progression on an individualised basis, but a substantial proportion of men with a high probability of harbouring Ins-PCa are at risk for pathologic understaging and/or undergrading. Thus, there is an ongoing need for identifying novel and more accurate predictors of Ins-PCa to improve the distinction between insignificant versus significant disease and thus to promote the adequate management of PCa patients at low risk for progression.

CONCLUSIONS

The exciting challenge of obtaining the pretreatment diagnostic tools that can really distinguish insignificant from significant PCa should be one of the main objectives of urologists in the following years to decrease the risk of overtreatment of Ins-PCa.

Tumor focality in prostate cancer: implications for focal therapy

In recent years, there has been a growing interest in focal treatment for prostate cancer. Although widely used for the treatment of tumors of the breast and kidney, focal treatment for prostate cancer remains a controversial area. Criticism of focal prostate therapy has been based on the fact that prostate cancer is a multifocal disease. Until now, little attention has been paid to distinguishing between men with unifocal and those with multifocal disease because such information has little clinical relevance when treatment is aimed at the whole gland irrespective of the volume or number of cancers in the prostate. In this Review, we summarize existing knowledge and examine the issue of prostate cancer focality in the context of focal treatment.

Are predictive models for cancer volume clinically useful in localized prostate cancer?

OBJECTIVES

To evaluate the correlation between preoperatively predicted and pathologically measured prostate cancer volumes and to investigate the clinical use of preoperatively predicted cancer volume in predicting pathological stage.

METHODS

Correlations between pathological findings and various preoperative parameters, including the cancer volumes as predicted by using two methods (Vca and estimated PCvol), were analyzed in 196 patients who underwent radical prostatectomy for clinically localized prostate cancer.

RESULTS

Pathologically measured prostate cancer volume was significantly correlated with the Vca and estimated PCvol, but the correlation coefficients were respectively only 0.46 and 0.35. Prostate-specific antigen (PSA), PSA density (PSAD), primary Gleason score, Vca, Vca fraction (Vcafx), and estimated PCvol were significantly higher in 82 patients with extraprostatic cancer than in 114 patients with organ-confined cancer. Magnetic resonance imaging (MRI) findings were significantly correlated with pathological stage. Multivariate logistic regression analysis indicated that the Vcafx and MRI findings were significant predictors of extraprostatic cancer, but receiver operating characteristic analysis revealed that the combination of Vcafx and MRI findings had no advantage over the combination of Gleason score, PSAD, and MRI findings.

CONCLUSIONS

Vca and estimated PCvol are significantly correlated with the pathologically measured cancer volume but their ability to accurately predict cancer volume is limited. Vcafx and MRI findings were statistically significant predictors of extraprostatic cancer but their combination was not superior to the combination of Gleason score, PSAD, and MRI findings.

Informatics in radiology: comparison of logistic regression and artificial neural network models in breast cancer risk estimation

Computer models in medical diagnosis are being developed to help physicians differentiate between healthy patients and patients with disease. These models can aid in successful decision making by allowing calculation of disease likelihood on the basis of known patient characteristics and clinical test results. Two of the most frequently used computer models in clinical risk estimation are logistic regression and an artificial neural network. A study was conducted to review and compare these two models, elucidate the advantages and disadvantages of each, and provide criteria for model selection. The two models were used for estimation of breast cancer risk on the basis of mammographic descriptors and demographic risk factors. Although they demonstrated similar performance, the two models have unique characteristics-strengths as well as limitations-that must be considered and may prove complementary in contributing to improved clinical decision making.

The clinical management of patients with a small volume of prostatic cancer on biopsy: what are the risks of progression? A systematic review and meta-analysis

Clinically localized prostate cancer is associated with a wide variation in biologic behavior, and men with the less aggressive form of the disease may never develop symptoms. There has been a rise in prostate cancer incidence in countries in which the blood test for prostatic-specific antigen (PSA) is common, and concerns have been expressed that this may be because of the increased detection of indolent disease, subjecting these men to unnecessary treatment and associated side effects. For the current review, the authors conducted a systematic evaluation of the literature regarding the outcomes of men who were diagnosed on the basis of a small volume of cancer in prostatic biopsies. The results indicated that, despite differences in study design and reporting, a significant proportion of patients with microfocal cancer, regardless of how it was defined, had adverse pathologic findings and a significant risk of PSA recurrence after undergoing radical prostatectomy. Biochemical and clinical recurrences also were observed after radiotherapy or watchful waiting. The authors concluded that patients with microfocal carcinoma on biopsy should be advised that their disease is not necessarily "insignificant" and should be counseled accordingly.

Reprint of: Stromogenic prostatic carcinoma pattern (carcinomas with reactive stromal grade 3) in needle biopsies predicts biochemical recurrence-free survival in patients after radical prostatectomy

We previously reported that reactive stromal grading in radical prostatectomies is a predictor of recurrence and that reactive stromal grading 0 and 3 are associated with lower biochemical recurrence-free survival rates than reactive stromal grading 1 and 2. We explored the prognostic significance of reactive stromal grading in preoperative needle biopsies. At Baylor College of Medicine, 224 cases of prostatic carcinoma were diagnosed by needle biopsy. Reactive stromal grading was evaluated on hematoxylin-eosin (H&E)-stained sections on the basis of previously described criteria: grade 0, with 0% to 5% reactive stroma; grade 1, 6% to 15%; grade 2, 16% to 50%; grade 3, 51% to 100%, or at least a 1:1 ratio between glands and stroma. Kaplan-Meier and Cox proportional hazard analyses were used. Reactive stromal grading distribution was as follows: reactive stromal grading 0, 1 case (0.5%); reactive stromal grading 1, 149 cases (66.5%); reactive stromal grading 2, 59 cases (26.3%); reactive stromal grading 3, 15 cases (6.7%). Reactive stromal grading in biopsies was correlated with adverse clinicopathologic parameters in the prostatectomy. Patients with reactive stromal grading 1 and 2 had better survival than those with 0 and 3 (P = .0034). Reactive stromal grading was an independent predictor of recurrence (hazard ratio = 1.953; P = .0174). Reactive stromal grading is independent of Gleason 4 + 3 and 3 + 4 in patients with a Gleason score of 7. Quantitation of reactive stroma and recognition of the stromogenic carcinoma in H&E-stained biopsies is useful to predict biochemical recurrence in prostate carcinoma patients independent of Gleason grade and prostate-specific antigen.

Optimized Prostate Brachytherapy Minimizes the Prognostic Impact of Percent of Biopsy Cores Involved With Adenocarcinoma

PURPOSE

A higher percent of positive biopsy cores predicts poor biochemical failure-free survival. The highest dose covering at least 90% of the prostate is a standard method of measuring implant quality. We tested the hypothesis that the percentage of positive biopsy cores loses its adverse prognostic impact in patients who receive implants with a highest dose covering at least 90% of the prostate of 100% or greater of the prescription dose.

MATERIALS AND METHODS

A total of 568 patients with intermediate to high risk adenocarcinoma of the prostate who were previously treated with brachytherapy in a prospective, randomized study were evaluated. The relationship between the percentage of positive biopsy cores, the highest dose covering at least 90% of the prostate and biochemical failure was examined.

RESULTS

At a median followup of 50 months the rate of 5-year biochemical failure-free survival was 87% for the entire group and 92% vs 81% for patients with less than 50% vs 50% or greater positive biopsy cores (log rank p = 0.009). The mean highest dose covering at least 90% of the prostate was statistically lower in failing vs nonfailing cases (p = 0.03). Gleason score, prostate specific antigen, 50% or greater positive biopsy cores and the highest dose covering at least 90% of the prostate were the only statistically significant predictive factors for biochemical failure-free survival on multivariate Cox regression analysis. When regression analysis was restricted to the 237 patients who received implants with a highest dose covering at least 90% of the prostate of 100% or greater, 50% or greater positive biopsy cores lost predictive value but prostate specific antigen and Gleason score remained independent prognostic factors.

CONCLUSIONS

A total of 50% or greater positive biopsy cores is an independent predictor of poor biochemical failure-free survival in patients treated with brachytherapy. High quality prostate brachytherapy, defined by a highest dose covering at least 90% of the prostate of 100% or greater, minimize the adverse effect of 50% or greater positive biopsy cores on time to biochemical failure.

Stromogenic prostatic carcinoma pattern (carcinomas with reactive stromal grade 3) in needle biopsies predicts biochemical recurrence-free survival in patients after radical prostatectomy

We previously reported that reactive stromal grading in radical prostatectomies is a predictor of recurrence and that reactive stromal grading 0 and 3 are associated with lower biochemical recurrence-free survival rates than reactive stromal grading 1 and 2. We explored the prognostic significance of reactive stromal grading in preoperative needle biopsies. At Baylor College of Medicine, 224 cases of prostatic carcinoma were diagnosed by needle biopsy. Reactive stromal grading was evaluated on hematoxylin-eosin (H&E)-stained sections on the basis of previously described criteria: grade 0, with 0% to 5% reactive stroma; grade 1, 6% to 15%; grade 2, 16% to 50%; grade 3, 51% to 100%, or at least a 1:1 ratio between glands and stroma. Kaplan-Meier and Cox proportional hazard analyses were used. Reactive stromal grading distribution was as follows: reactive stromal grading 0, 1 case (0.5%); reactive stromal grading 1, 149 cases (66.5%); reactive stromal grading 2, 59 cases (26.3%); reactive stromal grading 3, 15 cases (6.7%). Reactive stromal grading in biopsies was correlated with adverse clinicopathologic parameters in the prostatectomy. Patients with reactive stromal grading 1 and 2 had better survival than those with 0 and 3 (P = .0034). Reactive stromal grading was an independent predictor of recurrence (hazard ratio = 1.953; P = .0174). Reactive stromal grading is independent of Gleason 4 + 3 and 3 + 4 in patients with a Gleason score of 7. Quantitation of reactive stroma and recognition of the stromogenic carcinoma in H&E-stained biopsies is useful to predict biochemical recurrence in prostate carcinoma patients independent of Gleason grade and prostate-specific antigen.

Implementation of a map in radical prostatectomy specimen allows visual estimation of tumor volume

INTRODUCTION

Tumor volume is one of the best documented prognostic factors for prostate cancer. There are several methods to gain this important parameter but unfortunately most of the clinicians in the world do not get this information in their routine practice from the pathologist. We developed a standardized method to handle radical prostatectomy specimens including a special form of mapping in order to document relevant morphological data. The aim of this study was to investigate if our model of mapping prostate cancer, which we use in routine practice, may serve for visual estimation of tumor volume.

METHODS

We estimated the tumor volume of prostate cancer by visual estimation of 350 maps of radical prostatectomy specimens and correlated these data with established prognostic parameters and clinical outcome.

RESULTS

Significant correlations between tumor volumes, as obtained from our mapping, and known prognostic parameters such as preoperative serum levels of prostatic specific antigen, loss of differentiation, histological grade, lymph node metastasis, and margins were found. In a multivariate analysis, only Gleason score and tumor stage were shown to be independent prognostic parameters.

DISCUSSION

We demonstrate that mapping of prostate cancer is more than a simple method of documentation but may serve as a method for visual estimation of tumor volume of prostate cancer after radical prostatectomy. This method can further be used for a visual documentation of the tumor stage independent of changes in the TNM classification. The method is inexpensive and practicable and can therefore be applied in routine surgical pathology.

Should prostate cancer status be determined in patients undergoing radical cystoprostatectomy?

INTRODUCTION

We estimate the frequency of prostate cancers detected incidentally in radical cystoprostatectomy specimens and discuss whether the prostate cancer status should be determined in patients undergoing radical cystoprostatectomy.

MATERIALS AND METHODS

A total of 97 radical cystoprostatectomies without evidence of prostate cancer on digital rectal examination were performed for transitional cell carcinomas of the bladder between January 2001 and May 2004. The mean patient age at the time of surgery was 66.9 +/- 9.52 (range 49-75) years.

RESULTS

The overall incidence of prostate cancer detected in radical cystoprostatectomy specimens was 21.6% (21/97 specimens). The mean tumor volume was found to be 0.93 +/- 0.81 ml. The tumor volume was >0.5 ml in 12 cases (57.1%). The surgical margin was negative in all cases, and the disease was organ confined in 20 patients (95.2%). Capsular invasion was evident in 2 patients (9.5%), 1 of whom had lymph-node-positive disease.

CONCLUSIONS

Despite the high prevalence of incidental prostate carcinomas among patients with bladder cancer undergoing cystoprostatectomy, the vast majority of the cancers are organ confined. However, the prostate cancer status should be determined on the basis of digital rectal examination and prostate-specific antigen in patients undergoing radical cystoprostatectomy - especially if prostate-sparing cystectomy is planned.

Prognostic factors in prostate cancer

Prognostic factors in organ confined prostate cancer will reflect survival after surgical radical prostatectomy. Gleason score, tumour volume, surgical margins and Ki-67 index have the most significant prognosticators. Also the origins from the transitional zone, p53 status in cancer tissue, stage, and aneuploidy have shown prognostic significance. Progression-associated features include Gleason score, stage, and capsular invasion, but PSA is also highly significant. Progression can also be predicted with biological markers (E-cadherin, microvessel density, and aneuploidy) with high level of significance. Other prognostic features of clinical or PSA-associated progression include age, IGF-1, p27, and Ki-67. In patients who were treated with radiotherapy the survival was potentially predictable with age, race and p53, but available research on other markers is limited. The most significant published survival-associated prognosticators of prostate cancer with extension outside prostate are microvessel density and total blood PSA. However, survival can potentially be predicted by other markers like androgen receptor, and Ki-67-positive cell fraction. In advanced prostate cancer nuclear morphometry and Gleason score are the most highly significant progression-associated prognosticators. In conclusion, Gleason score, capsular invasion, blood PSA, stage, and aneuploidy are the best markers of progression in organ confined disease. Other biological markers are less important. In advanced disease Gleason score and nuclear morphometry can be used as predictors of progression. Compound prognostic factors based on combinations of single prognosticators, or on gene expression profiles (tested by DNA arrays) are promising, but clinically relevant data is still lacking.

Prediction of the volume of large prostate cancers by multiple core biopsies

OBJECTIVE

To evaluate whether large-volume prostate cancers can be predicted by means of multiple needle biopsies.

MATERIAL AND METHODS

In 115 men, 8-14 (mean 10) biopsies were taken, including eight from standardized positions (apex, mid-medial, mid-lateral and base). Biopsies were reviewed, the length of the cancer measured and the percentage cancer length calculated. All men underwent radical prostatectomy. The prostatectomy specimens were totally embedded and the tumor volume was measured planimetrically. The predictive values of the number and percentage of cores positive for cancer, cancer length and percentage cancer length were calculated for tumor volumes of >4, >6 and >8 ml.

RESULTS

Using univariate logistic regression, cancer length and percentage cancer length predicted tumor volumes of >4 (p<0.001), >6 (p<0.001) and >8 ml (p<0.05). These measures were better predictors of tumor volume than the number and percentage of cores positive for cancer. A biopsy cancer length of > or =30 mm and a percentage cancer length of > or =25% predicted a tumor volume of >4 ml in 95% and 93% of cases, respectively. For tumor volumes of >6 or >8 ml, predictive values were lower. Tumor volumes of <2 and <4 ml were found in 13% and 35%, respectively of men with as many as six positive cores, indicating that the number of positive cores was less useful as a predictor of tumor volume than the cancer length.

CONCLUSIONS

Cancer length and percentage cancer length are significant predictors of large tumor volumes. It is recommended that the linear extent of cancer in prostate biopsies should be reported by the pathologist.

Prostate Cancer Volume – Can It Be Predicted Preoperatively?

INTRODUCTION

The prostate cancer volume (PCvol) is described as a significant predictor for tumor progression after radical prostatectomy, but its determination has not become a routine procedure yet due to high demands on technical standards, labor intensity, and costs. The objective of this study is to predict the PCvol by using common preoperative variables.

MATERIAL AND METHODS

Between 1996 and 2001, 365 whole-mounted prostatectomy specimens, processed according to the Stanford protocol, were used for computerized reconstruction of the total PCvol. Widely accepted preoperative variables such as prostate-specific antigen (PSA), digital rectal examination findings, and Gleason score and grading (WHO) of the biopsy cores were correlated and analyzed for a relation to the PCvol by Spearman rho method and Mann-Whitney U test. Integrating these parameters in a multiple linear regression model, independent variables predicting the PCvol were determined, multiplied by their risk factors, and used for calculation of the estimated PCvol. In order to evaluate the precision of our results, we correlated measured and estimated tumor volumes. A nomogram was constructed, in order to visualize our results.

RESULTS

Multiple linear regression analysis revealed categorized PSA, grading (WHO), and Gleason score to be independent predictors for the PCvol. The estimated PCvol ranged from 0.5 to 9.8 cm(3) and the measured PCvol from 0.02 to 53 cm(3). An identical mean value of 4.1 cm(3) was observed. The Spearman rho method showed a highly significant correlation (coefficient = 0.5) between estimated and measured PCvol (p < 0.001).

CONCLUSIONS

The PCvol is regarded as a significant predictive parameter of tumor progression after radical prostatectomy, but due to its time-consuming determination, it has not become a routine procedure yet. Currently used preoperative parameters such as PSA and grading (WHO) and Gleason score of the biopsy cores do predict the total tumor volume. These results were reconfirmed by correlation analysis. Consequently, by use of our nomogram, the labor-intensive measurement of the PCvol becomes unnecessary.

Relating biopsy and clinical variables to radical prostatectomy findings: Can insignificant and advanced prostate cancer be predicted in a screening population?

OBJECTIVES

To assess the capacity of several clinical and needle biopsy pathologic parameters to predict insignificant and advanced prostate carcinoma (CaP) in radical prostatectomy tissue from men enrolled in a prostate-specific antigen screening program.

METHODS

We captured multiple clinical variables and measures of needle biopsy tumor extent from 152 men with Stage T1c CaP with a mean of six biopsy cores who were treated with radical prostatectomy. Insignificant CaP was defined as a tumor volume of less than 0.5 cm(3) that was organ confined with a Gleason score less than 7. Advanced CaP was defined by a formula that combined the Gleason score, pathologic stage, and margin status. Bivariate and logistic regression analyses were used to identify variables predictive of either insignificant or advanced CaP.

RESULTS

Of the cases of CaP, 25.7% were pathologically insignificant, and 14.5% were pathologically advanced. The best model for predicting insignificant CaP was less than 10% tumor as the greatest percentage of carcinoma in any core and a biopsy Gleason score of less than 7, yielding a sensitivity of 76.9% and specificity of 75.2%. For predicting advanced CaP, the best model was a total biopsy length of CaP greater than 3 mm, Gleason high-grade pattern 4 or 5 disease, perineural invasion in the biopsy, and more than one in six biopsy cores containing CaP, yielding a sensitivity of 13.6% and specificity of 100%.

CONCLUSIONS

The prediction of insignificant and advanced CaP on an individual basis in patients from a prostate-specific antigen screening study is a challenging problem. However, several histopathologic features of CaP in needle biopsy tissue contain useful information about the severity of disease.

Detection of prostate cancer in men with prostate-specific antigen levels of 2.0 to 4.0 ng/mL equivalent to that in men with 4.1 to 10.0 ng/mL in a Japanese population

OBJECTIVES

To analyze prospectively whether prostate cancer (CaP) incidence differs between Japanese men with a prostate-specific antigen (PSA) level of 2.0 to 4.0 ng/mL and those with a PSA level of 4.1 to 10.0 ng/mL.

METHODS

Men 79 years old or younger who were referred to our clinic were screened for CaP. Individuals with PSA levels of 2.0 ng/mL or greater were recommended for transrectal prostate biopsy. The prebiopsy clinical characteristics, cancer detection rate, and pathologic findings from the needle biopsy and prostatectomy specimen were compared between the low (2.0 to 4.0 ng/mL) and intermediate (4.1 to 10.0 ng/mL) PSA groups.

RESULTS

Of 858 patients screened for CaP, 440 with benign findings on digital rectal examination met the criteria, and 274 (62.3%) underwent biopsy. Of those undergoing biopsy, 110 and 123 patients had a low or an intermediate PSA level, respectively. Men in the low PSA group had a higher free/total PSA ratio, smaller prostate volume, and lower PSA density compared with those in the intermediate PSA group. CaP was diagnosed in 26 (23.6%) of 110 in the low and 29 (23.6%) of 123 in the intermediate PSA group. No statistically significant difference was found between the two groups in the pathologic findings of needle biopsy, including Gleason score, number of cores per biopsy, percentage of positive cores, and cancer length in the positive cores.

CONCLUSIONS

No statistically significant difference was found in the incidence of CaP (23.6%) between men with low and intermediate PSA levels in a Japanese population. The diagnostic yield was comparable to that reported for both white and black men.

Pathologic characterization of prostate cancers with a very low serum prostate specific antigen (0–2 ng/mL) incidental to cystoprostatectomy: is PSA a useful indicator of clinical significance?

Cystoprostatectomy specimens removed for bladder malignancy (1988-2000) at two referral centers (Mayo Clinic, Rochester, MN, The University Hospital of Innsbruck, Innsbruck, Austria) were examined for the coincidental finding of prostate cancer (PCA). Centralized examination of the prostate by a single uropathologist was performed if at the time of surgery the patient's serum PSA was < or =2.0 ng/mL and there were no suspicious lesions by digital prostate examination. Pathologic grade, stage, morphometric volume, number of tumor foci and association with areas of high grade prostatic intraepithelial neoplasia (HGPIN) were assessed by light microscopy. DNA ploidy and cellular proliferative index were assessed through digital image analysis. Clinically significant cancers were defined as tumors with > or =0.5 cc volume, Gleason 4 or 5 architecture, pT3, positive surgical margin, multifocality >3, nondiploid DNA content or proliferation index >5%. From nearly 1600 cystoprostatectomy specimens, 129 met the enrollment criteria. Thirty-patients (23%) within this group had PCA identified. Sixty percent of these tumors met the criteria for a clinically significant cancer. Nondiploid nuclear content was present in 17%. HGPIN was present in 70% and directly abutting carcinoma in 86% of prostates. The biologic activity of PCA appears to be independent of serum PSA. Any future definition of a clinically significant PCA should not be solely based upon histologic criteria, but needs to encompass clinical parameters (age, co-morbidities) and a noninvasive assessment of tumor volume and biologic doubling time.

Utility of the percentage of positive prostate biopsies in predicting PSA outcome after radiotherapy for patients with clinically localized prostate cancer

PURPOSE

To determine the utility of the percentage of positive prostate biopsies (PPPB) in predicting prostate-specific antigen (PSA) outcome after external beam radiotherapy alone.

METHODS AND MATERIALS

The records of 750 clinical Stage T1 and T2 patients treated by external beam radiotherapy alone with a median follow-up of 80 months were reviewed. Of the 750 patients, 345 were eligible for analysis; 255 (74%) had undergone sextant biopsies, 28 (8%) <6 biopsies, and 62 (18%) >6 biopsies. The pretreatment PSA level (<10, 10-20, >20 ng/mL), biopsy Gleason score (2-6, 7, 8-10), and clinical stage (T1-T2a, T2b, T2c), uni- or bilateral positive biopsy, radiation dose, and PPPB were analyzed as potential predictors of PSA outcome. The PPPB data were analyzed as a continuous and as a categorical variable.

RESULTS

PPPB was a significant predictor of the time to PSA failure on univariate analysis as a continuous (p = 0.0053) and as a categorical (<50% vs. >or=50%, p = 0.0077) variable. In multivariate analysis, a trend was noted for worse 5-year PSA failure-free survival based on PPPB >or=50% vs. <50% (p = 0.082). Sixty-four patients experienced biochemical failure according to the American Society for Therapeutic Radiology Oncology definition. The 5-year PSA failure-free survival rate was 79% vs. 69% (p = 0.02) and the clinical disease-free survival rate was 97% vs. 86% (p = 0.0004) for patients with <50% vs. >or=50% PPPB. PPPB was not a significant predictor for the time to PSA failure within the traditional risk groups (low, intermediate, and high) on multivariate analysis.

CONCLUSION

PPPB was a predictor of post-external beam radiotherapy PSA outcome in clinically localized prostate cancer; but in this cohort it did not provide additional information beyond the traditional risk stratification schema.

The reporting of prostate cancer on needle biopsy: prognostic and therapeutic implications and the utility of diagnostic markers

Prostate needle biopsy remains the gold standard for diagnosing prostate cancer. Prostate cancer on needle biopsy can be evaluated by numerous techniques of quantifying tumour extent, Gleason score, and the presence of perineural invasion (PNI). These modalities can help clinicians in assessing the risk of extraprostatic disease, progression likelihood, and in helping men with prostate cancer choose among therapeutic options. This review details the information that should be included in the routine pathology report. Recent advances in molecular biology of prostate carcinogenesis have identified many molecular markers for prostate cancer. While several are extremely promising as diagnostic immunohistochemical markers, other prognostic markers are not yet ready to be used in routine practice until they are validated by large prospective studies.

Transition zone biopsy and prediction of extraprostatic extension at radical prostatectomy

BACKGROUND

There is limited data in the literature that suggests that transition zone (TZ) biopsy might be useful for the prediction of extraprostatic extension (EPE) in clinically localized prostate cancer. We studied the role of TZ biopsy in the prediction of EPE.

METHODS

Transition zone biopsies were performed in addition to systematic peripheral zone (PZ) biopsies between November 1995 and December 1999. During this period, 59 patients underwent radical prostatectomy for clinically localized disease. Final pathological results were compared with preoperative clinical and biopsy findings.

RESULTS

Of the 59 patients who underwent radical prostatectomy, 46 had cancer only in the PZ cores and 13 had cancer both in the PZ and the TZ cores at the biopsy. Final histopathological results revealed EPE in 19 (32%) patients and positive surgical margins in 22 (37%). In univariate analysis of age, prostate-specific antigen (PSA), mean percentage of positive PZ cores, mean biopsy Gleason score and positive TZ biopsy, there was a significant difference for serum PSA levels (P = 0.021), presence of positive TZ cores (P = 0.018) and percentage of positive PZ cores in patients with and without EPE (P < 0.001). In multivariate analysis, the single independent predictor of EPE was the percentage of positive PZ biopsy cores (P = 0.0227). There was agreement between the side of positive TZ biopsy and EPE in seven of eight patients.

CONCLUSION

Taking two TZ cores in addition to peripheral sextant biopsy did not result in better prediction of EPE. The relationship between TZ involvement and the presence of EPE can be investigated further in radical prostatectomy specimens.

Pathological and molecular aspects of prostate cancer

This review focuses on new findings and controversial issues in the the pathology and molecular biology of adenocarcinoma of the prostate. Since management of high-grade prostatic intraepithelial neoplasia on needle biopsy--the most common precursor lesion to prostate cancer--is the crucial issue with this lesion, we discuss the risk of cancer subsequent to this histological diagnosis and the issue of whether such neoplasia should be regarded as carcinoma-in-situ. We also look at prostate cancer itself, starting with its diagnosis, reporting on needle biopsy, and reviewing how the most frequently used grading system, the Gleason grading system, affects treatment. The molecular basis of prostate cancer includes inheritable and somatic genetic changes (tumour suppressor genes, loss of heterozygosity, gene targets and regions of chromosomal gain, CpG island promoter methylation, invasion and metastasis suppressor genes, telomere shortening, and genetic instability). Changed gene expression (eg, proliferation-related genes, changes in the androgen receptor, apoptosis and stress-response genes) have potential as biomarkers and therapeutic targets in prostate cancer.

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.

Carcinoma extent in prostate needle biopsy tissue in the prediction of whole gland tumor volume in a screening population

Increasing prostate tumor volume has been shown to correlate with numerous adverse prognostic indicators for patients with prostate carcinoma The ability to predict tumor volume from pretreatment parameters is potentially critical in the stratification of patients for different management strategies. We assessed the capacity of preoperative variables to predict tumor volume in 100 men diagnosed with prostate cancer in a prostate-specific antigen (PSA)-based screening program. Preoperative information included total serum PSA concentration and needle biopsy tissue variables, including Gleason score, number of positive cores, linear extent of carcinoma in millimeters, greatest percentage of carcinoma (in a single core), total percentage of carcinoma (all cores), presence of perineural invasion, and percentage of high-grade carcinoma. The postoperative end point was total tumor volume in radical prostatectomy tissue, calculated by image analysis. We determined independently significant factors and generated a predictive modelfor whole gland tumor volume. Total tumor volume was related significantly in multivariate analysis to 3 preoperative variables: linear extent of carcinoma, exponential number of positive cores, and serum PSA. A predictive model generated based on these 3 variables accounted for only 65% of the natural deviance of the data owing to data-point scatter for individual patients, suggesting that additional variables are needed to more accurately predict tumor volume. Findings highlight the importance of reporting quantitative measures of tumor amount in prostate needle biopsy specimens; several measures of tumor extent (vs 1 measure) provide maximal information on prostate cancer size.

Biological selection criteria for radical prostatectomy

Tumors clinically confined to the prostate gland (T1-2) are heterogeneous with respect to pathological staging and outcome after definitive radical surgery (radical prostatectomy). The preoperative prognostic factors that could predict pathological stage and outcome of individual patients with clinically localized prostate cancer are reviewed. New preoperative factors have been identified by histological analysis of needle biopsy prostate specimens in addition to Gleason grading score, serum markers (PSA), and clinical staging. These factors are related to tumor volume, zonal origin of the tumor, and spread into the gland and surrounding tissues. Other biological factors are identified by molecular and immunohistochemical analysis (neuroendocrine differentiation, DNA content, microvessel density, and perineural invasion). Biomolecular factors can also be assessed preoperatively on serum samples (free/total PSA ratio, PSA RT-PCR). Although only a few of these factors have a role in predicting treatment failure and/or disease recurrence, the neural network analysis seems to be the most important tool for identifying patients with more aggressive disease. A combination of these new factors, also using neural networks, could be relevant in the preoperative management of patients with prostate cancer to identify those with confined disease and to select those suitable for a "nerve sparing radical prostatectomy" to preserve sexual function and to achieve definitive cancer control.

Does site-specific labelling and individual processing of sextant biopsies improve the accuracy of prostate biopsy in predicting pathological stage in patients with T1c prostate cancer?

OBJECTIVE

To evaluate whether individual labelling and processing of the sextant of origin improves the accuracy of prostate biopsy in predicting the final pathological stage after radical prostatectomy in patients with T1c prostate cancer.

PATIENTS AND METHODS

The charts of 386 patients treated for prostate cancer by radical prostatectomy between January 1996 and June 1999 were reviewed. In all, 124 patients fulfilled the following inclusion criteria: no abnormality on digital rectal examination (DRE) or transrectal ultrasonography, a prostate specific antigen (PSA) level before biopsy of < or = 20 ng/mL, and prostate cancer diagnosed after one set of random sextant biopsies, with the cores being submitted in six separate containers individually labelled for the sextant of origin.

RESULTS

Within this series of patients with a low tumour burden, the preoperative PSA, biopsy Gleason score and unilateral vs bilateral involvement were not significant predictors of disease extension. The percentage of positive cores and the number and topography of positive sextants were both statistically significant predictors of organ-confined disease. Although these two variables appeared to be statistically equivalent on a first analysis in the overall series, a subgroup of patients was identified who benefited from the complete topographical information, i.e. those 52 (42%) patients with a Gleason score of < 7, 25-75% positive biopsies and < or =3 positive sextants.

CONCLUSION

These results support the individual labelling of biopsy cores in selected patients with a normal DRE and a moderately elevated PSA, as it helps to better predict the final pathological stage. This substantial benefit outweighs the additional effort by the pathologist.

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.

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.

A quantitative model for the dynamics of serum prostate-specific antigen as a marker for cancerous growth: an explanation for a medical anomaly

Prostate-specific antigen (PSA) is an enzyme produced by both normal and cancerous prostate epithelial cells. Although PSA is the most widely used serum marker to detect and follow patients with prostatic adenocarcinoma, there are certain anomalies in the values of serum levels of PSA that are not understood. We developed a mathematical model for the dynamics of serum levels of PSA as a function of the tumor volume. Our model results show good agreement with experimental observations and provide an explanation for the existence of significant prostatic tumor mass despite a low-serum PSA. This result can be very useful in enhancing the use of serum PSA levels as a marker for cancer growth.

Discrepancies between Gleason scores of needle biopsy and radical prostatectomy specimens

The purpose of this study was to determine the accuracy of Gleason scores in prostate needle biopsy diagnosis and to investigate factors affecting the accuracy of the tumor grade. A single pathologist reviewed 116 sets of prostate cancer biopsies and radical prostatectomy specimens. The following factors were examined to determine their effect on the accuracy of the biopsy Gleason scores: (i) relative tumor differentiation; (ii) pathological stage; (iii) amount of tissue in the biopsy specimen; (iv) amount of cancer tissue in the biopsy specimen; (v) tumor heterogeneity; (vi) clinical findings (prostate specific antigen value and digital rectal examination); and (vii) interobserver variability. In 53 cases the Gleason score of biopsy specimens was identical to the score of prostatectomy specimens (45.7%). Fifty-four cases (46.6%) of biopsy specimens were undergraded. The most common discrepancy was diagnosis of well-differentiated carcinoma in the biopsy but diagnosis of moderately differentiated tumor in the corresponding prostatectomy specimen. This discrepancy occurred when the amount of tumor in the biopsy was 3 mm or less. Biopsy and prostatectomy results showed less agreement when the original biopsy tumor grade rendered by nine different pathologists was used, suggesting that interobserver variability can adversely affect the accuracy of tumor grade. Clarifying the histologic criteria for distinguishing each grade, especially between Gleason grades 2 and 3, is important for accurate grading.

History of ultrasound in nephrourology

Abdominal ultrasound (US) started from nephrourology with the representation of sections of the kidney or urinary bladder in the 1950s. Doppler signals from renal vessels were first recorded in 1976. Prostatic US was only achieved after the practical use of transrectal sonography in 1967. At present, US is an indispensable tool for diagnosis in any organ in the field of nephrourology.

The clinical utility of the percent of positive prostate biopsies in predicting biochemical outcome following external-beam radiation therapy for patients with clinically localized prostate cancer

PURPOSE

An investigation was performed of the clinical utility of the percent of positive prostate biopsies in predicting prostate-specific antigen (PSA) outcome following external-beam radiation therapy (RT) for men with PSA-detected or clinically palpable prostate cancer.

METHODS AND MATERIALS

A Cox regression multivariable analysis was used to determine whether the percent of positive prostate biopsies provided clinically relevant information about PSA outcome following external beam RT in 473 men while accounting for the previously established risk groups based on the pretreatment PSA level, biopsy Gleason score, and the 1992 American Joint Commission on Cancer (AJCC) clinical T stage.

RESULTS

Controlling for the known prognostic factors, the percent of positive prostate biopsies added clinically significant information (p = 0.02) regarding time to PSA failure following RT. Specifically, 76% of the patients in the intermediate risk group (1992 AJCC T(2b) or biopsy Gleason 7 or PSA > 10 ng/mL and < or = 20 ng/mL) could be classified into either an 30% or 85% 5-year PSA control cohort using the preoperative prostate biopsy data.

CONCLUSION

The previously validated stratification of PSA outcome following radical prostatectomy (RP) using the percent of positive prostate biopsies in intermediate-risk patients is also clinically significant for men treated with external beam RT. The percent positive prostate biopsies should be considered in conjunction with the PSA level, biopsy Gleason score, and 1992 AJCC clinical T stage when counseling patients with newly diagnosed and clinically localized prostate cancer about PSA outcome following RP or external beam RT.

Optimizing patient selection for prostate monotherapy

PURPOSE

Patients at low risk for prostate-specific antigen (PSA) failure following definitive local therapy are those with PSA of 10 or less, biopsy Gleason Score of 6 or less, and 1992 American Joint Committee on Cancer (AJCC) clinical Stage T1c or T2a. However, low-risk patients managed with radical prostatectomy and found to have prostatectomy Gleason score > or = 3+4 have a less favorable PSA outcome when compared to patients with prostatectomy Gleason score < or = 3+3. This study was performed to determine whether the percentage of positive prostate biopsy cores could predict upgrading from a biopsy Gleason score of 6 or less to a prostatectomy Gleason score > or = 3+4 in low-risk patients to optimize selection for prostate only radiation therapy.

METHODS AND MATERIALS

Concordance testing of the biopsy Gleason score and the primary and secondary prostatectomy Gleason grades was performed in 427 prostate cancer patients treated with radical prostatectomy and at low risk for PSA failure. Logistic regression multivariable analysis was performed to test the ability of the established prognostic factors and the percentage of positive prostate biopsies (<34%, 34-50%, >50%) to predict for upgrading from biopsy Gleason score of 6 or less prostatectomy Gleason score > or = 3+4. PSA failure-free survival was reported using the actuarial method of Kaplan and Meier and comparisons were made using a log-rank test.

RESULTS

Twenty-nine percent of the 427 study patients were upgraded from a biopsy Gleason score of 6 or less to a prostatectomy Gleason score > or = 3+4. The presence of greater than 50% positive biopsies was the only significant factor for predicting the upgrading from biopsy Gleason score of 6 or less to prostatectomy Gleason score > or = 3+4 on logistic regression multivariable analysis with the variables treated as continuous and categorical. Specifically, upgrading occurred in 26% vs. 59% of patients with 50% or less vs. greater than 50% positive biopsies, respectively. This translated into a 5-year PSA failure-free survival which was significantly higher (92% vs. 62%, p = 0.00001) for men with 50% or less vs. greater than 50% positive prostate biopsies, respectively.

CONCLUSION

The presence of greater than 50% positive biopsies was associated with higher rates of pathologic upgrading which translated into lower 5-year PSA failure-free survival following radical prostatectomy (RP). Therefore, the percentage of positive biopsies may be useful in optimizing the selection of low-risk patients for prostate only radiation therapy such as external beam radiation or implant monotherapy.

Prostate Cancer - Old Problems and New Approaches. (Part II. Diagnostic and Prognostic Markers, Pathology and Biological Aspects)

Diagnostic and prognostic markers for prostatic cancer (PCa) include conventional protein markers (e.g., PAP, PSA, PSMA, PIP, OA-519, Ki-67, PCNA, TF, collagenase, and TIMP 1), angiogenesis indicator (e.g., factor VIII), neuroendocrine differentiation status, adhesion molecules (E-cadherin, integrin), bone matrix degrading products (e.g., ICPT), as well as molecular markers (e.g., PSA, PSMA, p53, 12-LOX, and MSI). Currently, only PSA is used clinically for early diagnosis and monitoring of PCa. The histological differential diagnosis of prostatic adenocarcinoma includes normal tissues such as Cowper's gland, paraganglion tissue and seminal vesicle or ejaculatory duct as well as pathological conditions such as atypical adenomatous hyperplasia, atrophy, basal cell hyperplasia and sclerosing adenosis. A common PCa is characterized by a remarkable heterogeneity in terms of its differentiation, microscopic growth patterns and biological aggressiveness. Most PCa are multifocal with signi ficant variations in tumor grade between anatomically separated tumor foci. The Gleason grading system which recognizes five major grades defined by patterns of neoplastic growth has gained almost uniform acceptance. In predicting the biologic behavior of PCa clinical and pathological stages are used as the major prognostic indicators. Among the cell proliferation and death regulators androgens are critical survival factors for normal prostate epithelial cells as well as for the androgen-dependent human prostatic cancer cells. The androgen ablation has been shown to increase the apoptotic index in prostatic cancer patients and castration also promotes apoptotic death of human prostate carcinoma grown in mice. The progression of PCa, similarly to other malignancies, is a multistep process, accompanied by genetic and epigenetic changes, involving phenomenons as adhesion, invasion and angiogenesis (without prostate specific features).

Prognostic factors in prostate cancer. College of American Pathologists Consensus Statement 1999

BACKGROUND

Under the auspices of the College of American Pathologists, a multidisciplinary group of clinicians, pathologists, and statisticians considered prognostic and predictive factors in prostate cancer and stratified them into categories reflecting the strength of published evidence and taking into account the expert opinions of the Prostate Working Group members.

MATERIALS AND METHODS

Factors were ranked according to the previous College of American Pathologists categorical rankings: category I, factors proven to be of prognostic importance and useful in clinical patient management; category II, factors that have been extensively studied biologically and clinically but whose importance remains to be validated in statistically robust studies; and category III, all other factors not sufficiently studied to demonstrate their prognostic value. Factors in categories I and II were considered with respect to variations in methods of analysis, interpretation of findings, reporting of data, and statistical evaluation. For each factor, detailed recommendations for improvement were made. Recommendations were based on the following aims: (1) increasing uniformity and completeness of pathologic evaluation of tumor specimens, (2) enhancing the quality of data collected pertaining to existing prognostic factors, and (3) improving patient care.

RESULTS AND CONCLUSIONS

Factors ranked in category I included preoperative serum prostate-specific antigen level, TNM stage grouping, histologic grade as Gleason score, and surgical margin status. Category II factors included tumor volume, histologic type, and DNA ploidy. Factors in category III included perineural invasion, neuroendocrine differentiation, microvessel density, nuclear roundness, chromatin texture, other karyometric factors, proliferation markers, prostate-specific antigen derivatives, and other factors (oncogenes, tumor suppressor genes, apoptosis genes, etc).

Clinical utility of the percentage of positive prostate biopsies in defining biochemical outcome after radical prostatectomy for patients with clinically localized prostate cancer

PURPOSE

To determine the clinical utility of the percentage of positive prostate biopsies in predicting prostate-specific antigen (PSA) outcome after radical prostatectomy (RP) for men with PSA-detected or clinically palpable prostate cancer.

METHODS

A Cox regression multivariable analysis was used to determine whether the percentage of positive prostate biopsies provided clinically relevant information about PSA outcome after RP in 960 men while accounting for the previously established risk groups that are defined according to pretreatment PSA level, biopsy Gleason score, and the 1992 American Joint Committee on Cancer (AJCC) clinical T stage. The findings were then tested using an independent surgical database that included data for 823 men.

RESULTS

Controlling for the known prognostic factors, the percentage of positive prostate biopsies added clinically significant information (P <.0001) regarding time to PSA failure after RP. Specifically, 80% of the patients in the intermediate-risk group (1992 AJCC T2b, or biopsy Gleason 7 or PSA > 10 ng/mL and </= 20 ng/mL) could be classified into either an 11% or 86% 4-year PSA control cohort using the preoperative prostate biopsy data. These findings were validated in the intermediate-risk patients using an independent surgical data set.

CONCLUSION

The validated stratification of PSA outcome after RP using the percentage of positive prostate biopsies in intermediate-risk patients is clinically significant. This information can be used to identify men with newly diagnosed and clinically localized prostate cancer who are at high risk for early (</= 2 years) PSA failure and, therefore, may benefit from the use of adjuvant therapy.

Prostate cancer sampled on sextant needle biopsy: significance of cancer on multiple cores from different areas of the prostate

OBJECTIVES

To determine the relationship between the location of positive sites, when more than one sextant site shows prostate cancer in a given patient, and pathologic stage, tumor volume, and margin status if radical prostatectomy is performed.

METHODS

We performed biopsies using a spring-loaded biopsy gun on 343 Stage T1c (nonpalpable) radical prostatectomy specimens from each sextant site.

RESULTS

In 56 cases, carcinoma was identified in two separate sextant sites. In 38 cases, the sites were vertical to each other (ie, left apex, left mid); in 8 cases, the sites were diagonal (ie, left apex, right mid); in 5 cases, the sites were horizontal (ie, left apex, right apex); and in 5 cases, they were not contiguous but were separated by an uninvolved sextant site (ie, left apex, left base). Tumors were more likely to be multifocal in cases with diagonally positive biopsies (P <0.0001) and horizontally positive biopsies (P <0.0001) than in those with vertically positive biopsies. No significant differences were found in organ-confined status and margin positivity among cases with different positive biopsy locations. The dominant tumor nodule was larger (mean 2.76 cc) in cases with noncontiguously positive biopsies than in all other groups combined (mean 1.44 cc) (P = 0.017).

CONCLUSIONS

When more than one sextant site shows cancer, there are differences in terms of whether the tumors sampled are multifocal versus solitary depending on which sites are positive. However, no significant differences were found in predicting pathologic stage and margin positivity.

American Brachytherapy Society (ABS) recommendations for transperineal permanent brachytherapy of prostate cancer

PURPOSE/OBJECTIVE

To develop and disseminate the American Brachytherapy Society (ABS) recommendations for the clinical quality assurance and guidelines of permanent transperineal prostate brachytherapy with 125I or 103Pd.

METHODS AND MATERIALS

The ABS formed a committee of experts in prostate brachytherapy to develop consensus guidelines through a critical analysis of published data supplemented by their clinical experience. The recommendations of the panels were reviewed and approved by the Board of Directors of the ABS.

RESULTS

Patients with high probability of organ-confined disease are appropriately treated with brachytherapy alone. Brachytherapy candidates with a significant risk of extraprostatic extension should be treated with supplemental external beam radiation therapy (EBRT). Patient selection guidelines were developed. Dosimetric planning of the implant should be carried out for all patients before seed insertion. A modified peripheral loading is preferred. The AAPM TG-43 recommendations requiring a change in prescription dose for 125I sources should be universally implemented. The recommended prescription doses for monotherapy are 145 Gy for 125I and 115-120 Gy for 103Pd. The corresponding boost doses (after 40-50 Gy EBRT) are 100-110 Gy and 80-90 Gy, respectively. Clinical evidence to guide selection of radionuclide (103Pd or 125I) is lacking. Post implant dosimetry and evaluation must be performed on all patients. It is suggested that the dose that covers 90% (D90) and 100% (D100) of the prostate volume and the percentage of the prostate volume receiving the prescribed dose (V100) be obtained from a dose-volume histogram (DVH) and reported.

CONCLUSION

Guidelines for appropriate patient selection, dose reporting, and improved quality of permanent prostate brachytherapy are presented. These broad recommendations are intended to be technical and advisory in nature, but the ultimate responsibility for the medical decisions rests with the treating physician. This is a constantly evolving field, and the recommendations are subject to modifications as new data becomes available.