Early detection of prostate cancer with low PSA cut-off values leads to significant stage migration in radical prostatectomy specimens

PSA density of the lesion: a mathematical formula that uses clinical and pathological data to predict biochemical recurrence in prostate cancer patients

A main challenge in the clinical management of prostate cancer is to identify which tumor is aggressive and needs invasive treatment. Thus, being able to predict which cancer will progress to biochemical recurrence is a great strategy to stratify prostate cancer patients. With that in mind, we created a mathematical formula that takes into account the patients clinical and pathological data resulting in a quantitative variable, called PSA density of the lesion, which has the potential to predict biochemical recurrence. To test if our variable is able to predict biochemical recurrence, we use a cohort of 219 prostate cancer patients, associating our new variable and classic parameters of prostate cancer with biochemical recurrence. Total PSA, lesion weight, volume and classic PSA density were positively associated with biochemical recurrence (p<0.05). ISUP score was also associated with biochemical recurrence in both biopsy and surgical specimen (p<0.001). The increase of PSA density of the lesion was significantly associated with the biochemical recurrence (p=0.03). Variables derived from the formula, PSA 15% and PSA 152, were also positive associated with the biochemical recurrence (p=0.01 and p=0.002 respectively). Logistic regression analysis shows that classic PSA density, PSA density of the lesion and total PSA, together, can explain up to 13% of cases of biochemical recurrence. PSA density of the lesion alone would have the ability to explain up to 7% of cases of biochemical recurrence. In conclusion, this new mathematical approach could be a useful tool to predict disease recurrence in prostate cancer.

Specific spatial distribution patterns of tumor foci are associated with a low risk of biochemical recurrence in pT2pN0R0 prostate cancer

BACKGROUND

The previous attempts for pT2 substaging of prostate cancer (PCa) were insufficient in providing prognostic subgroups and the search for new prognostic parameters to subcategorize pT2 PCa is, therefore, needed. Therefore, the current study investigated the association between tumor distribution patterns and the biochemical recurrence (BCR)-free survival rate in pT2pN0R0 PCa.

METHODS

Following radical prostatectomy, the anatomical distribution of PCa in 743 men with pT1-pT3pN0 disease was analyzed to determine 20 types of PCa distribution patterns. Then, 245 men with pT2pN0R0 PCa was considered for prognostic evaluation with a mean follow-up period of 60 months. The spatial distribution patterns of PCa were evaluated using a cMDX^©-based map model of the prostate. An analysis including 552,049 comparison operations was performed to assist in the evaluation of the similarity levels of the distribution patterns. A k-mean cluster analysis was applied to determine groups with similar distribution patterns. A decision-tree analysis was performed to divide these groups according to frequency of BCR. The BCR-free survival rate was analyzed using Kaplan-Meier curves. Predictors of progression were investigated using a Cox proportional hazards model.

RESULTS

BCR occurred in 8.2% of the 245 men with pT2pN0R0 PCa. The median time of recurrence was 60 months (interquartile range [IQR]: 42-77). In univariate and multivariate analyses, the prostate volume and the distribution patterns were independent predictors for BCR, whereas the sub-staging of pT2 tumors, Gleason grading, prostate-specific antigen (PSA) level, and relative tumor volume were not. In the patients with pT2pN0R0 disease, PCa distribution patterns with the apical involvement were significantly associated with the risk of BCR (P = 0.001).

CONCLUSION

The spread tumor patterns with the apical involvement are associated with a high-risk of BCR in the pT2 tumor stage. The vertical tumor spread could be considered in developing improved prognostic pT2 sub-categories.

MMP-9 Overexpression Due to TIMP-1 and RECK Underexpression is Associated with Prognosis in Prostate Cancer

Background

Extracellular matrix homeostasis is strictly maintained by a coordinated balance between the expression of metalloproteinases (MMPs) and their inhibitors. The purpose of this study was to investigate whether the expression of MMP-9 and its specific inhibitors, TIMP-1 and RECK, are expressed in a reproducible, specific pattern and if the profiles are related to prognosis and clinical outcome in prostate cancer (PC).

Methods

MMP-9, TIMP-1, and RECK expression levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) in fresh-frozen malignant tissue specimens collected from 79 patients with clinically localized PC submitted to radical prostatectomy (RP). Frozen benign prostatic tissue from another 10 men with prostate cancer, also submitted to RP, was analyzed to determine if the profile of gene expression was maintained. The control group consisted of 11 patients with benign prostate hyperplasia (BPH).

Results

In the tumor samples, MMP-9 was overexpressed by 9.2 times, and TIMP-1 and RECK were underexpressed (0.75 and 0.80 times, respectively). Overexpression of MMP-9 was significantly related to PSA levels above 10 ng/mL (p=0.033). In addition, MMP-9 overexpression was related to biochemical recurrence, with a marginal statistical significance (p=0.089). MMP-9 was also overexpressed in benign tissues of patients with PC, as were TIMP-1 and RECK, in contrast to their underexpression in tumor samples.

Conclusion

Our results show that MMP-9 is overexpressed and its negative regulators are underexpressed in PC tissue, emphasizing a possible role of MMP-9 in the carcinogenesis process. Additionally, we noticed a relationship between MMP-9 overexpression and increased levels of PSA, an important prognostic factor. In benign tissue adjacent to tumors, the MMP-9 equilibrium is likely maintained because the expression of its negative regulators is preserved.

Changes in pathologic outcomes and operative trends with robot-assisted laparoscopic radical prostatectomy

Introduction:

We hypothesized that there is a reverse stage migration, or a shift toward operating on higher-risk prostate cancer, in patients undergoing robot-assisted laparoscopic prostatectomy (RALP). We therefore evaluated the stage of disease at the time of surgery for patients with prostate cancer at a large tertiary academic medical center.

Materials and Methods:

After institutional review board approval, we reviewed all patients that had undergone robotic prostatectomy. These patients were separated into three categories: An early era of 2005-2008, intermediate era of 2009-2010, and a current era of 2011-2012.

Results:

A total of 3451 patients underwent robotic prostatectomy from 2005 to 2012. The proportion men with clinical T1 tumors declined from 88.3% in the early era to 72.2% in the current era (P < 0.0001). Men with preoperative biopsy Gleason 6 disease decreased from the early to the current era (P < 0.0001), while men with preoperative biopsy Gleason ≥ 8 showed the opposite trend, increasing from the early to the current era (P = 0.0002). From the early to the current era, the proportion of patients with National Comprehensive Cancer Network (NCCN) low risk prostate cancer decreased, while those with NCCN intermediate and high-risk disease increased. The proportion of pathologic T3 disease increased from 15.5% in the early to 30.6% in the current era (P < 0.0001). On the other hand, the proportion of pathologic T2/+ SMS (surgical margin status) decreased from 6.6% in the early era to 3.1% in the current era (P = 0.0002).

Conclusions:

We have demonstrated a reverse stage migration in men undergoing robotic prostatectomy. Despite the increasing proportion of men with extra-capsular disease undergoing RALP, the surgical margin status has remained similar. This could reflect both the changing dynamics of the population opting for surgery as well as the learning curve of the surgeons.

Prostate cancer Ki-67 (MIB-1) expression, perineural invasion, and gleason score as biopsy-based predictors of prostate cancer mortality: the Mayo model

OBJECTIVE

To determine the role of cellular proliferation and other biopsy-based features in the prediction of prostate cancer mortality.

PATIENTS AND METHODS

Between 1993 and 2012, our institution has performed quantitation of prostate cancer DNA ploidy and Ki-67 (MIB-1) on most prostate cancer needle biopsy specimens. The outcomes of 451 consecutive patients with biopsy-proven cancer treated by radical prostatectomy between January 24, 1995, and December 29, 1998, without neoadjuvant hormonal therapy were assessed. Clinical and biopsy information obtained before radical prostatectomy was placed in multivariate Cox proportional hazards regression models to predict local or systemic progression and cancer-specific death. Predictive ability was evaluated using a concordance index.

RESULTS

With a median follow-up of 12.9 years, 46 patients experienced local or systemic progression, and 18 patients died of prostate cancer. On multivariate analysis, the biopsy features of Ki-67 expression, perineural invasion, and Gleason score were associated with local or systemic progression. Ki-67 expression, perineural invasion, and Gleason score were associated with cancer-specific death with a concordance index of 0.892. After adjusting for perineural invasion and Gleason score, each 1% increase in Ki-67 expression was associated with a 12% increased risk of cancer-specific death (P<.001). Ki-67 expression alone was a strong predictor of cancer-specific outcomes and improved the predictive ability of currently used algorithms.

CONCLUSION

This study documents that long-term prostate cancer outcomes are best estimated with a combination of Gleason score, perineural invasion, and Ki-67 expression. Given its low cost, rapid assessment, and strong predictive power, we believe that adding Ki-67 expression to perineural invasion and Gleason score at biopsy should be considered a standard by which all new biomarkers are compared before introducing them into clinical practice.

Underexpression of MMP-2 and its regulators, TIMP2, MT1-MMP and IL-8, is associated with prostate cancer

OBJECTIVE

Extracellular matrix homeostasis is strictly maintained by a coordinated balance between the expression of metalloproteinases (MMPs) and their regulators. The purpose of this study was to investigate whether MMP-2 and its specifi c regulators, TIMP-2, MT1-MMP and IL-8, are expressed in a reproducible, specific pattern and if the profiles are related to prognosis and clinical outcome of prostate cancer (PCa).

MATERIALS AND METHODS

MMP-2, TIMP-2, MT1-MMP and IL-8 expression levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) in freshly frozen malignant and benign tissue specimens collected from 79 patients with clinically localized PCa who underwent radical prostatectomies. The control group consisted of 11 patients with benign prostate hyperplasia (BPH). The expression profile of the MMP-2 and its regulators were compared using Gleason scores, pathological stage, pre-operative PSA levels and the fi nal outcome of the PCa.

RESULTS

The analysis of 79 specimens of PCa revealed that MMP-2, TIMP-2, MT1-MMP and IL-8 were underexpressed at 60.0%, 72.2%, 62.0% and 65.8%, respectively, in malignant prostatic tissue in relation to BPH samples. Considering the prognostic parameters, we demonstrated that high Gleason score tumors (≥ 7) overexpressed MMP-2 (p = 0.048) and TIMP-2 (p = 0.021), compared to low Gleason score tumors (< 7).

CONCLUSION

We have demonstrated that MMP-2 and its regulators are underexpressed in PCa. Alternatively, overexpression of MMP-2 and TIMP-2 was related to higher Gleason score tumors. We postulate that alterations in metalloproteinase expression may be important in the control of tissue homeostasis related to prostate carcinogenesis and tumor behavior.

miR-21 may acts as an oncomir by targeting RECK, a matrix metalloproteinase regulator, in prostate cancer

Background

Prognosis of prostate cancer (PCa) is based mainly in histological aspects together with PSA serum levels that not always reflect the real aggressive potential of the neoplasia. The micro RNA (miRNA) mir-21 has been shown to regulate invasiveness in cancer through translational repression of the Metaloproteinase (MMP) inhibitor RECK. Our aim is to investigate the levels of expression of RECK and miR-21 in PCa comparing with classical prognostic factors and disease outcome and also test if RECK is a target of miR-21 in in vitro study using PCa cell line.

Materials and methods

To determine if RECK is a target of miR-21 in prostate cancer we performed an in vitro assay with PCa cell line DU-145 transfected with pre-miR-21 and anti-miR-21. To determine miR-21 and RECK expression levels in PCa samples we performed quantitative real-time polymerase chain reaction (qRT-PCR).

Results

The in vitro assays showed a decrease in expression levels of RECK after transfection with pre-miR-21, and an increase of MMP9 that is regulated by RECK compared to PCa cells treated with anti-miR-21. We defined three profiles to compare the prognostic factors. The first was characterized by miR-21 and RECK underexpression (N = 25) the second was characterized by miR-21 overexpression and RECK underexpression (N = 12), and the third was characterized by miR-21 underexpression and RECK overexpression (N = 16). From men who presented the second profile (miR-21 overexpression and RECK underexpression) 91.7% were staged pT3. For the other two groups 48.0%, and 46.7% of patients were staged pT3 (p = 0.025).

Conclusions

Our results demonstrate RECK as a target of miR-21. We believe that miR-21 may be important in PCa progression through its regulation of RECK, a known regulator of tumor cell invasion.

Characteristics and outcome of prostate cancer with PSA <4 ng/ml at diagnosis: a population-based study

This population-based study aims to assess prognosis of prostate cancer diagnosed with prostate-specific antigen (PSA) levels <4 ng/ml in routine care. Materials and methods We compared prostate cancer patients with low PSA values (n=59) with other prostate cancer patients (n=1330) by logistic regression and the Cox model using data from the Geneva Cancer Registry. Results Patients with low PSA values more frequently had early-stage and well differentiated tumours. Nevertheless, 35% presented with aggressive tumour characteristics or metastases. After adjustment for other prognostic factors, prostate cancer-specific mortality was similar for both groups (hazard ratio: 1.1; 95%CI: 0.6-2.2). Conclusion We conclude that cancer with low PSA values at diagnosis is not indolent.

Prostate cancer screening strategies with re-screening interval determined by individual baseline prostate-specific antigen values are cost-effective

AIMS

To determine whether prostate cancer screening strategies with re-screening interval determined by individual baseline prostate-specific antigen values are cost-effective.

METHODS

Based on the results of an actual contemporary screening program, we established Markov decision analytic models of prostate cancer screening with personalized re-screening interval strategies using cutoff baseline PSA levels for biennial screening as well as a model of uniformly annual or biennial screening. These strategies were compared in terms of cumulative incidence of early cancer and cost-effectiveness.

RESULTS

Early cancer detection rates were similar among all strategies. Personalized strategies were more cost-effective compared to uniform screening strategies. If all participants with negative PSA results uniformly omit annual screening, it would be more costly but less effective (dominated). Contrary, annual screening for all participants would cost too much. These results were robust throughout sensitivity analysis incorporating every assumption in the models.

CONCLUSIONS

This study adds important evidence that personalized rescreening strategies based on individual baseline PSA have advantages of cost-effectiveness against conventional uniform strategies.

Diagnosis of adenocarcinoma in prostate needle biopsy tissue

Prostate cancer is a major public health problem throughout the developed world. For patients with clinically localised prostate cancer, the diagnosis is typically established by histopathological examination of prostate needle biopsy samples. Major and minor criteria are used to establish the diagnosis, based on the microscopic appearance of slides stained using haematoxylin and eosin. Major criteria include an infiltrative glandular growth pattern, an absence of basal cells and nuclear atypia in the form of nucleomegaly and nucleolomegaly. In difficult cases, basal cell absence may be confirmed by immunohistochemical stains for high-molecular-weight cytokeratins (marked with antibody 34betaE12) or p63, which are basal cell markers. Minor criteria include intraluminal wispy blue mucin, pink amorphous secretions, mitotic figures, intraluminal crystalloids, adjacent high-grade prostatic intraepithelial neoplasia, amphophilic cytoplasm and nuclear hyperchromasia. Another useful diagnostic marker detectable by immunohistochemistry is alpha-methylacyl coenzyme A racemase (AMACR), an enzyme selectively expressed in neoplastic glandular epithelium. Cocktails of antibodies directed against basal cell markers and AMACR are particularly useful in evaluating small foci of atypical glands, and in substantiating a diagnosis of a minimal adenocarcinoma. Reporting of adenocarcinoma in needle biopsy specimens should always include the Gleason grade and measures of tumour extent in the needle core tissue. Measures of tumour extent are (1) number of cores positive for cancer in the number of cores examined, (2) percentage of needle core tissue affected by carcinoma and (3) linear millimetres of carcinoma present.

Relapse after radical prostatectomy correlates with preoperative PSA velocity and tumor volume: Results from a screening population

OBJECTIVES

To evaluate, in a screening population, the impact of tumor volume and prostate volume on prostate-specific antigen (PSA) velocity (PSAV) and to find predictors of biochemical failure after radical prostatectomy. Longitudinal PSA changes in men with prostate cancer have been reported to be significantly different from those without prostate cancer.

METHODS

PSAV was assessed in 102 men undergoing radical retropubic prostatectomy. The pathologic findings of specimens obtained at radical retropubic prostatectomy and pelvic lymph node dissection were analyzed separately for all patients.

RESULTS

The median preoperative PSA in the 102 patients was 6.4 ng/mL, the median prostate volume was 32.8 cm3, and the median tumor volume was 1.27 cm3. The PSAV correlated significantly with tumor volume (P <0.05) but not with prostate volume (P = 0.142). The median tumor volume in men with biochemical progression after radical retropubic prostatectomy was 2.55 cm3 versus 0.94 cm3 in men who were free of disease 5 years after surgery. The median PSAV in the year before diagnosis in men with relapse after radical prostatectomy was 1.98 ng/mL/yr versus 1.05 ng/mL/yr in men who had no evidence of disease.

CONCLUSIONS

The results of our study have shown that the main factor contributing to the PSAV in patients with prostate cancer is cancer load and that prostate volume is not significantly associated with the PSAV. Men with a PSAV of more than 2 ng/mL/yr in the year before cancer diagnosis are at a high risk of relapse. The PSAV may be helpful in identifying patients with small tumors and thus increase the detection rate of potentially curable prostate cancers.

Pathological outcomes and biochemical progression in men with T1c prostate cancer undergoing radical prostatectomy with prostate specific antigen 2.6 to 4.0 vs 4.1 to 6.0 ng/ml

PURPOSE

Recent studies have suggested that the cut point for recommending prostate biopsy among men with a normal digital rectal examination should be greater than 2.5 ng/ml as opposed to the more traditional greater than 4.0 ng/ml. We compared outcomes between men with clinical stage T1c disease undergoing radical prostatectomy who had a low vs slightly increased prostate specific antigen.

MATERIALS AND METHODS

The study population consisted of 2,896 men treated with radical prostatectomy between 1985 and 2004 at a tertiary care referral center with clinical stage T1c disease and a pre-biopsy prostate specific antigen between 2.6 and 6.0 ng/ml. Using multivariate analysis we evaluated the association between pre-biopsy prostate specific antigen 2.6 to 4.0 ng/ml (784) vs 4.1 to 6.0 ng/ml (2,112), and pathological outcomes and biochemical progression.

RESULTS

After adjusting for multiple clinical and pathological characteristics, lower preoperative serum prostate specific antigen values were associated with decreased odds of Gleason score 7 or greater in the surgical specimen (p = 0.004), positive surgical margins (p = 0.02) and extraprostatic extension (p = 0.001). There was no significant association between these preoperative prostate specific antigen groups and odds of seminal vesicle invasion (p = 0.47) or lymph node metastasis (p = 0.90). Among the 1,534 men with followup information available there was a trend for increased risk of biochemical progression associated with a higher preoperative prostate specific antigen, although this trend did not reach statistical significance (relative risk 1.48, 95% CI 0.69-3.19, p = 0.31).

CONCLUSIONS

In the current study of men with clinical stage T1c treated with radical prostatectomy a lower preoperative prostate specific antigen was associated with significantly more favorable pathological findings. Whether this degree of improved outcomes justifies the limitations associated with decreasing the prostate specific antigen cut point (eg increased biopsies performed and diagnosis of insignificant cancers) remains to be determined.

Detection rates and biologic significance of prostate cancer with PSA less than 4.0 ng/mL: observation and clinical implications from Tyrol screening project

OBJECTIVES

To investigate the prostate cancer (PCa) detection rates and Gleason scores in patients with serum prostate-specific antigen (PSA) levels of 2.0 to 3.9 ng/mL and 4.0 to 10 ng/mL (free PSA 18% or less), in a population-based screening project. With the use of prostate-specific antigen (PSA) screening, more PCa is being diagnosed at PSA values of less than 4 ng/mL.

METHODS

A total of 3446 consecutive screening volunteers with a PSA level of 2.0 to 10.0 ng/mL (free PSA 18% or less) were assessed. Ten systematic prostate biopsies and an additional five Doppler-enhanced targeted biopsies were performed on the basis of age-specific PSA reference ranges. The cumulative frequency of detection and the Gleason scores were analyzed.

RESULTS

The PCa detection rate for patients with a PSA value of 2.0 to 3.9 ng/mL (n = 1522, group 1) and 4.0 to 10.0 ng/mL (n = 1924, group 2) was 21% (n = 320) and 30% (n = 572), respectively. Of the PCa cases detected, 37% were in men with a PSA level of 2 to 4 ng/mL. Statistically significant differences were found in age and prostate volume between groups 1 and 2, with patients in the lower PSA group younger and having a smaller mean prostate volume (P = 0.0001). Of 313 patients with PCa and a PSA value of 2 to 3.9 ng/mL, 24% had a Gleason score of 7 or greater compared with 33% of 560 patients with a PSA value of 4.0 to 10.0 ng/mL (P = 0.004).

CONCLUSIONS

Our data suggest that in a screening population, more than one third of PCa cases in men with a PSA level of 2 to 10 ng/mL will occur in those with a PSA value of 2 to 3.9 ng/mL. Also, PCa cases with a low PSA level occur in younger patients and at lower stages with a smaller prostate volume.

Longitudinal PSA changes in men with and without prostate cancer: assessment of prostate cancer risk

BACKGROUND

To determine longitudinal PSA changes over a period of 10 years in patients with and without prostate cancer.

METHODS

Serial PSA measurements performed over 10 years were evaluated in 353 men who eventually developed prostate cancer and in 2.462 participants of a screening program without prostatic malignancy.

RESULTS

In men with cancer, mean tPSA increased from 2.28 ng/ml at 10 years before diagnosis to 6.37 ng/ml at the time of postive biopsy (PSA velocity: 0.409 ng/ml/year). PSA velocity was significantly associated with Gleason scores and pathologic stage. In the benign group (n=2.462), mean tPSA increased from 1.18 to 1.49 ng/ml over a period of 10 years (PSA velocity of 0.03 ng/ml/year). Of the subjects with tPSA levels of 2 ng/ml or less, 2 years prior to cancer diagnosis, 11.4% had tPSA values of more than 4 ng/ml at the time of biopsy. Of the 972 men with tPSA below 1 ng/ml 2 years before the most recent measurement was obtained, 966 (99.4%) had no evidence of prostate cancer 2 years later, while six were found to have malignancies (0.6%).

CONCLUSIONS

Longitudinal PSA changes in men with and without prostate cancer are significantly different. Annual testing may not be required in men with baseline tPSA levels of 1 ng/ml or below, whereas in patients with levels higher than 1 ng/ml, it seems to be indicated because of the significant percentage of men presenting with tPSA levels of more than 4 ng/ml two years later.

Improved detection of prostate cancer using classification and regression tree analysis

PURPOSE

To build a decision tree for patients suspected of having prostate cancer using classification and regression tree (CART) analysis.

PATIENTS AND METHODS

Data were uniformly collected on 1,433 referred men with a serum prostate-specific antigen (PSA) levels of < or = 10 ng/mL who underwent a prostate biopsy. Factors analyzed included demographic, laboratory, and ultrasound data (ie, hypoechoic lesions and PSA density [PSAD]). Twenty percent of the data was randomly selected and reserved for study validation. CART analysis was performed in two steps, initially using PSA and digital rectal examination (DRE) alone and subsequently using the remaining variables.

RESULTS

CART analysis selected a PSA cutoff of more than 1.55 ng/mL for further work-up, regardless of DRE findings. CART then selected the following subgroups at risk for a positive biopsy: (1) PSAD more than 0.165 ng/mL/cc; (2) PSAD < or = 0.165 ng/mL/cc and a hypoechoic lesion; (3) PSAD < or = 0.165 ng/mL/cc, no hypoechoic lesions, age older than 55.5 years, and prostate volume < or = 44.0 cc; and (4) PSAD < or = 0.165 ng/mL/cc, no hypoechoic lesions, age older than 55.5 years, and 50.25 cc less than prostate volume < or = 80.8 cc. In the validation data set, specificity and sensitivity were 31.3% and 96.6%, respectively. Cancers that were missed by the CART were Gleason score 6 or less in 93.4% of cases. Receiver operator characteristic curve analysis showed that CART and logistic regression models had similar accuracy (area under the curve = 0.74 v 0.72, respectively).

CONCLUSION

Application of CART analysis to the prostate biopsy decision results in a significant reduction in unnecessary biopsies while retaining a high degree of sensitivity when compared with the standard of performing a biopsy of all patients with an abnormal PSA or DRE.

Access of tumor-derived macromolecules and cells to the blood: an electron microscopical study of structural barriers in microvessel clusters in highly malignant primary prostate carcinomas

BACKGROUND

The neo-angiogenetic microvessels forming a major reactive stromal element in highly malignant prostate neoplasms may exhibit fine-structural features relevant to our understanding of the passage of macromolecules from tumor to blood, on the one hand, and of events facilitating the metastatic cascade, on the other hand.

METHODS

Ensuring rapid, optimal fixation in buffered glutaraldehyde was a foremost concern. Thin parings from radical prostatectomy specimens of Gleason scores (GS) 5-9 were taken from the tumor and from the contralateral side of the gland, glutaraldehyde-fixed, diced to smaller than 1 mm(3), postfixed in osmium tetroxide, embedded in Epon, ultrathin-sectioned, contrasted with lead and uranyl salts, and viewed in a transmission electron microscope.

RESULTS

In dysplastic tissue areas, intraductal microvessels located in gland ducts were occasionally observed, and found to be aggressively invasive and highly active in producing neo-angiogenetic sprouts. Closely spaced microvessel clusters contained almost exclusively neo-angiogenetic microvessels, which were in cell-cell contact with numerous ameboid migratory cells, some of which were likely to be tumor cells. In these microvessel clusters, all structural barriers hindering passage of tumor-derived molecules or cells to the blood were eliminated.

CONCLUSION

In microvessel clusters, the ultrastructural equivalent of microvascular hotspots, tumor invasion of microvessels is facilitated, but equally microvessels are observed invading the gland duct epithelial walls. This reciprocal invasivity of tumor cells and microvascular endothelial cells generates ideal conditions for tumor products and metastatic cells to enter the blood.

Variations in PSA doubling time in patients with prostate cancer on “watchful waiting”: Value of short-term PSADT determinations

OBJECTIVES

In watchful waiting patients with localized prostate cancer, the prostate-specific antigen doubling time (PSADT) has been suggested to correlate with disease progression and is often used to determine the need for therapy. In these studies, all available prostate-specific antigen data throughout the observation period were used to determine the PSADT. However, the correlation between the short-term and long-term assessments of PSADT in this population is unknown. Our aim was to determine the correlation between short-term PSADT measurements and long-term PSADT among men with prostate cancer on observation.

METHODS

In a prospective cohort of 108 watchful waiting patients, the correlation of the overall PSADT with the PSADT measured during short-term intervals was analyzed. The level of agreement in classifying patients as having a rapid PSADT (24 months or less) was also evaluated.

RESULTS

The median interval of observation was 36 months. According to the various methods used, the median PSADT was 82 months using all prostate-specific antigen values, 128 months using the first three values (early), 78 months using the last three values (late), and 144 months using the first and last values only (2-point). The PSADT measured over short-term intervals demonstrated a weak correlation with the overall PSADT (Spearman's rho 0.53 for early, 0.56 for late, and 0.50 for 2-point PSADT). A statistically significant agreement was noted in the classification of rapid PSADT between the overall PSADT measurement and early PSADT measurement (kappa 0.67). Less agreement was found in the classification, however, with the late and 2-point PSADT and the overall PSADT.

CONCLUSIONS

In untreated patients with localized prostate cancer, the PSADT varies considerably depending on the interval evaluated.

Potential pathologic markers for prostate chemoprevention studies

The field of exploring potential biomarkers for prostate cancer prevention continues to expand rapidly. In addition to a limited scope of histologic alterations, mainly PIN, a growing array of promising technologies (eg, computer-assisted analysis), and molecules involved in cell-cycle regulations, angiogenesis, and structural and numerical chromosomal alterations are potential candidates for surrogate endpoint biomarkers for prevention trials. Before any these potential candidates are adopted, however, the technical, interpretational, and validation requirements must be satisfied. More important, it is crucial to demonstrate that modulation of the frequency of the biomarker decreases the rate of cancer development.

Biochemical outcome after radical prostatectomy among men with normal preoperative serum prostate-specific antigen levels

BACKGROUND

Recent studies have shown that a significant number of men with normal prostate-specific antigen (PSA) levels have prostate carcinoma. Whether malignancies in such men are associated with better outcomes is unclear. The authors compared the risk of biochemical failure after radical prostatectomy (RP) between men with normal PSA levels and men with elevated PSA levels.

METHODS

Data were examined from 1582 men who underwent RP between 1988 and 2002 at 1 of 5 equal-access medical centers. Patients were segregated into groups based on serum PSA levels (with stratification according to age-specific reference ranges). Clinical and pathologic characteristics and biochemical outcome data were compared across groups using analyses of variance, log-rank tests, and Cox proportional hazards analysis.

RESULTS

Men who had normal PSA levels had significantly fewer high-grade tumors compared with men who had higher PSA levels (P < 0.001). The former group had a significantly decreased incidence of positive surgical margins, extracapsular disease, seminal vesicle invasion, and lymph node involvement (P < 0.001). On multivariate analysis, only serum PSA level (P < 0.001) and biopsy Gleason score (P < 0.001) predicted the time to disease recurrence. When only men with serum PSA levels < 10 ng/mL were examined, PSA level treated as a continuous variable remained a significant predictor of time to biochemical failure (P = 0.02).

CONCLUSIONS

Men who had normal PSA levels had significantly fewer high-grade tumors and significantly better biochemical outcomes after undergoing RP compared with men who had elevated PSA levels. Overall, men with normal PSA levels who undergo RP represent a favorable risk group.