Pathological Characteristics and Prognosis of Nonpalpable and Palpable Prostate Cancers with a Hybritech Prostate Specific Antigen of 4 to 10 ng./ml

Pathological Outcome in Men with Prostate Cancer Suitable for Active Surveillance after Radical Prostatectomy

Background:

Active surveillance (AS) as a treatment option for low risk prostate cancer is gaining recognition. We evaluate the validity of the AS protocol in our patient population, by defining the risk of undergrading and understaging in their pathology. We also aim to determine more accurate inclusion criteria, in order to improve the prediction of early low risk prostate cancer.

Materials and Methods:

Data was taken from our institutional prostate cancer registry for all men who underwent radical prostatectomy (RP) between Jan 2000 and June 2009. We determined if any of the patients would have met the University of Toronto's (UoT) AS inclusion criteria and examined their post-operative pathology. The primary end-point was pathological upgrading and upstaging. The individual inclusion factors i.e. preoperative PSA, were tested for statistical significance and better cutoffs. Univariate, multivariate and ROC curves were used in the statistical analysis.

Results:

216 RPs were performed between January 2000 and June 2009. We identified 79 men who fulfilled the UoT AS criteria. 35% of patients had a Gleason score upgrade from biopsy to surgery, and 21.5% of patients had an upstage to T3 disease. Overall, 34 (43%) patients had an unfavourable change in the grade and/or stage of their prostate cancer.

Conclusions:

There is a significant risk of undergrading and understaging with the current criteria used for AS. There is a need to identify more discriminative AS criteria before it can be offered as an option to patients with clinically early prostate cancer.

Undergrading and understaging in patients with clinically insignificant prostate cancer who underwent radical prostatectomy

PURPOSE

The aim of our study is to evaluate the undergrading and understaging rates in patients with clinically localized insignificant prostate cancer who underwent radical prostatectomy.

MATERIALS AND METHODS

Between July 2005 and July 2008, 406 patients underwent radical prostatectomy for clinical localized prostate cancer in our hospital. Based on preoperative data, 93 of these patients fulfilled our criteria of non-significance: Gleason score < 7, stage T1c, PSA < 10 ng/mL and percentage of affected fragments less than 25%. The pathologic stage and Gleason score were compared to preoperative data to evaluate the rate of understaging and undergrading. The biochemical recurrence free survival of these operated insignificant cancers were also evaluated.

RESULTS

On surgical specimen analysis 74.7% of patients had Gleason score of 6 or less and 25.3% had Gleason 7 or greater. Furthermore 8.3% of cases showed extracapsular extension. After 36 months of follow-up 3.4% had biochemical recurrence, defined by a PSA above 0.4 ng/mL.

CONCLUSIONS

Despite the limited number of cases, we have found considerable rates of undergrading and understaging in patients with prostate cancer whose current definitions classified them as candidates for active surveillance. According to our results the current definition seems inadequate as up to a third of patients had higher grade or cancer outside the prostate.

Frozen Section for the Management of Intraoperatively Detected Palpable Tumor Lesions During Nerve-Sparing Scheduled Radical Prostatectomy

OBJECTIVES

The intraoperative finding of palpable tumor lesions has been described as a contraindication for nerve-sparing (NS) radical prostatectomy (RP). However, its evaluation is subjective. Especially in patients with a strong demand to regain postoperative erectile function, a surgeon might be reluctant to sacrifice neurovascular bundles (NVBs) based on this information. We investigated the use of frozen section (FS) analysis to monitor the safety and efficiency of NS during RP in patients with intraoperatively identified subcapsular tumor lesions.

METHODS

In 83 of 608 patients, who underwent NS-RP, intraoperative FS was performed because of a lesion palpable close to the capsule. A wedge of 4cm in diameter including the lesion was cut off and stained differently for capsule and intraprostatic margin. In case of presence of carcinoma adherent to the capsule, the NVB was resected; otherwise, the NVB remained in situ.

RESULTS

Patients with palpable tumor lesions had pT3 tumors in 36% and 61% had Gleason 4 pattern, compared to 18% and 42% for the control group. Carcinoma was found in 93% of the FS specimens. In 42% of the FS samples, tumor had contact with the capsule and 14% of secondary resected NVB specimens demonstrated a carcinoma invasion. In 52% NVBs could be preserved despite an ipsilateral nodule without negatively affecting the margin status. However, the false-negative rate of the FSs was 6%. Conversely, FSs set the intraoperative decision to remove the NVB in 42% of FS patients, resulting in an additional 36% of negative margins.

CONCLUSIONS

In patients with intraoperatively detected tumor lesions during a NS planned RP, FS objectively supports the decision of secondary NVB resection as well as preservation.

Radical retropubic prostatectomy--results in 127 surgically treated patients

Radical prostatectomy represents an optimal therapeutic method in treatment of the localized prostatic carcinoma. It may be performed using retropubic, perineal, transcoccygeal or laparoscopic approach. In a multicenter study, the authors have analyzed 127 patients surgically treated in the period 1992 - 2003. All the patients were preoperatively diagnosed with the localized prostatic carcinoma. The patients were operated at the Clinic of Urology in Belgrade (92 patients) and other departments of urology in Serbia (35 patients). The youngest patient was 49 while the oldest one was 75 (mean age 64 years). The surgical procedure duration ranged between 60 and 120 minutes. Over the last five years, the need for blood transfusion was below 50%. All the patients underwent retropubic radical prostatectomy.

Nerve-sparing radical retropubic prostatectomy: techniques and clinical considerations

There are essentially two ways to accomplish nerve preservation during radical retropubic prostatectomy: the 'apical approach' described by Walsh and the so-called 'lateral approach', a simplified method where the dissection is initially conducted on the portion of the bundles that courses posterolateral to the prostate. Do the different techniques differ in the ability to preserve potency and in the positive surgical margins rate? No previous study has addressed this question. Above all, the preoperative and intraoperative indications to spare or not the nerves remain a matter of debate. The present review is an attempt to elucidate these questions in light of the current literature.

Expression of matrix metalloproteinases (MMP-2 and -9) and their inhibitors (TIMP-1 and -2) in prostate cancer tissue

Matrix metalloproteinases (MMPs) have been implicated in progression and metastases of different tumours. The balance between the MMPs and their natural inhibitors (tissue inhibitors of matrix metalloproteinases; TIMP) seems to be an important factor related to this role. Here, the expression of MMP-2 and -9 along with TIMP-1 and -2 was examined in prostate cancer tissue. A total of 40 radical prostatectomy specimens were embedded in paraffin and immunohistochemical staining was performed to detect MMP-2 and -9, and TIMP-1 and -2. The immunoreactivity was assessed semiquantitively using routine light microscopy. The intensity of staining was correlated to preoperative PSA, T category, Gleason score and clinical parameters of the specimens. The imbalance of MMPs and TIMPs was recognised as a significant loss of TIMP-1 in malignant epithelium and an upregulation of MMPs. Palpable tumours (T2, T3) expressed significantly more MMP-2 and significantly less MMP-9 than T1c tumours. Our data are in accordance with other literature reports in that an imbalance of MMPs and TIMPs is found in malignant tumours. The observed imbalance of MMP and TIMP is mainly caused by a loss of TIMP-1. Furthermore, palpable tumours demonstrated significantly more MMP-2 and significantly less MMP-9 expression than nonpalpable tumours.

Anterior distribution of Stage T1c nonpalpable tumors in radical prostatectomy specimens

OBJECTIVES

To determine the anatomic patterns of tumor distribution in radical prostatectomy specimens from nonpalpable prostate cancer.

METHODS

Tumor maps directly traced from histologic slides of 62 radical prostatectomy specimens were superimposed by a computer-assisted imaging technique to create an idealized prostate gland at three levels: apex, mid-prostate, and base. To investigate specific patterns of tumor distribution, the sites of tumor in each quadrant were compared according to risk group stratification. The tumor extent was compared with the patterns of positivity in routine sextant biopsies.

RESULTS

Among all patients, the tumor frequency was 85.5% in the mid-gland, 82.3% in the apex, and 48.4% in the base. Analysis by quadrant showed that tumors were significantly denser in the apex to mid-prostate. The primary extent of these tumors appeared to lie predominantly in the anterior half of the gland. Biopsy yields at the apex and mid-prostate appeared low compared with the frequency of cancers at these levels. No patterns specific to the different risk groups were found, but no tumors within the anterior base were found in the low-risk group.

CONCLUSIONS

The primary extent of nonpalpable tumors appeared to lie predominantly in the anterior half of the gland at the apex to mid-prostate levels. Additional biopsy cores taken from more anterior regions of the gland may enhance the detection of nonpalpable cancers further.

Molecular staging of surgical margins after radical prostatectomy by detection of telomerase activity

BACKGROUND

The further course of prostate cancer (PC) after radical prostatectomy (RPX) is decisively influenced by the local tumor stage. Although it is thus far possible to assess the risk of local recurrence from the pathohistology, precise predictions cannot be made. A more precise evaluation would be desirable, mainly for early planning of adjuvant therapy. Other authors have shown that telomerase activity may be a marker for malignant potential. We assessed the detection of telomerase activity using the telomeric repeat amplification protocol (TRAP) in surgical margins compared to conventional histopathological examination.

METHODS

Ninety-two patients with local PC who underwent RPX were examined. After RPX biopsies were obtained from four defined areas of the prostatic fossa and processed by TRAP assay for telomerase activity using a standard protocol.

RESULTS

In 5 of 48 patients (10.4%) with organ-confined prostate carcinoma (pT2) telomerase activity could be detected. Seven of 47 patients (14.9%) with locally advanced PC (> pT2) had at least one positive specimen.

CONCLUSIONS

The results obtained in our study indicate that detection of telomerase activity by TRAP assay may be a suitable parameter for molecular staging of surgical margins, because of the high tumor-specificity. Further follow-up must clarify whether patients with positive molecular detection have an increased risk of local recurrence.

Impact of preoperative serum PSA level from 0 to 10 ng/ml on pathological findings and disease-free survival after radical prostatectomy

BACKGROUND

To determine the impact of various preoperative serum prostate specific antigen (PSA) levels in the range from 0.1 to 10 ng/ml on pathological stage and disease-free survival after radical prostatectomy.

METHODS

We selected a cohort of 585 patients who underwent radical prostatectomy between 1991-1996 for clinically localized prostate cancer and presented with preoperative serum PSA levels from 0.1 to 10 ng/ml.

RESULTS

Pathological organ-confined disease was present in 57.6% of patients. The rate of organ-confined disease decreased from an average of 85% for patients with a PSA value < 2 ng/ml, to 46.8% for patients with a PSA value > 7 ng/ml. We found statistically significant correlations between preoperative serum PSA level and overall pathological stage (P = 0.001), pathologically organ-confined disease (P = 0.001), margin positive rates (P = 0.001), extra prostatic extension (P = 0.001), and seminal vesicle invasion (P = 0.001). The overall disease-free survival rate was 87%, with a median follow up of 42.4 months. Disease free survival was significantly better for patients with PSA up to 4 ng/ml (P = 0.005).

CONCLUSIONS

Our data suggests that PSA detection programs should strive to detect prostate cancer in men before the PSA level rises above 7 ng/ml. In addition, since patients with a PSA level < 4 ng/ml had better disease-free survival rates than those with a PSA level between 4.1-10 ng/ml, eliminating an arbitrary cutoff of 4 ng/ml, may lead to improved disease-free survival.

Reverse transcriptase-polymerase chain reaction for prostate-specific antigen in the molecular staging of pelvic surgical margins after radical prostatectomy

OBJECTIVES

To examine the application of reverse transcriptase-polymerase chain reaction (RT-PCR) to assist in prostate-specific antigen (PSA) detection in the surgical margins after radical prostatectomy (RP). The risk of local recurrence increases considerably in the presence of extracapsular tumor growth and/or positive surgical margins at RP. Although this makes it possible to identify patients with an increased risk of local recurrence, precise predictions cannot be made. A more precise assessment is desirable mainly for early planning of adjuvant therapy.

METHODS

Ninety-five patients with clinically organ-confined prostate cancer (CaP) underwent RP. After removing the gland, biopsies were obtained from four defined areas of the prostatic fossa and processed for RT-PCR for PSA detection. Sixteen patients with muscle-invasive bladder carcinoma who underwent radical cystoprostatectomy served as controls.

RESULTS

Thirty-two of 95 patients with CaP (35%) had at least one positive molecular margin indicating an expression for PSA; 19 of 48 (39%) of these had an organ-confined tumor stage according to conventional histology and 13 of 47 (28%) had tumor growth beyond the prostate. A statistically significant correlation between the frequency of positive molecular margins and clinical data was only observed in the group with disease greater than Stage pT2. All controls had negative molecular margins (P = 0.012).

CONCLUSIONS

On the basis of the results obtained, molecular diagnostic RT-PCR for PSA detection in the surgical margins after RP seems to be an interesting supplementary tool for monitoring the course and establishing the prognosis. Long-term follow-up of these patients is needed to demonstrate the clinical value of molecular diagnostics of surgical margins during RP.

Most prostate cancers missed by raising the upper limit of normal prostate-specific antigen for men in their sixties are clinically significant

OBJECTIVES

To evaluate the efficacy of applying an age-specific prostate-specific antigen (PSA) reference range to determine whether prostate biopsies are warranted in men 60 to 69 years of age. We estimated the incidence of clinically significant prostate cancer in men in their sixties with PSA levels of 4.01 to 4.50 ng/mL and normal digital rectal examinations (DRE).

METHODS

We reviewed 203 sextant prostate biopsies of men in their sixties with PSA levels of 4.01 to 4.50 ng/mL and normal DRE. Tumors were considered clinically significant if the cancer on biopsy was poorly differentiated (Gleason score of 7 or more), involved more than one core, or included a single focus measuring more than 3 mm.

RESULTS

The positive biopsy rate was 31.5%. More than 80% of the cancers detected satisfied criteria that almost always predict clinically significant cancer. Thus, among men in their sixties with PSA levels of 4.01 to 4.50 ng/mL and normal DRE, the risk of detecting clinically significant cancer on biopsy was approximately 25%.

CONCLUSIONS

Most nonpalpable cancers detected by sextant biopsies in men 60 to 69 years of age with PSA levels of 4.01 to 4.5 ng/mL are clinically significant. Applying an age-specific PSA reference range that increases the upper limit of normal PSA to 4.5 ng/mL results in the failure to detect a substantial number of clinically significant cancers.

Comparison of pathologic characteristics of T1c and non-T1c cancers detected in a population-based screening study, the European Randomized Study of Screening for Prostate Cancer

In recent years the introduction of serum prostate-specific antigen (PSA) determination as a screening tool for early detection of prostate cancer in asymptomatic men has led to a markedly increased detection of prostate cancers that are neither palpable nor visible with transrectal ultrasonography (stage T1c). In this preliminary study we assessed pathologic features and aspects that are indicative of clinical significance in T1c tumors and tumors with palpable or visible lesions (non-T1c tumors). Between June 1994 and December 1995, 51 consecutive radical prostatectomies were performed on screened participants in the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer (ERSPC). After determination of pathologic stage and Gleason score, morphometric analysis was performed to determine tumor volume. Radical prostatectomy specimens were divided into three mutually exclusive subsets: T1c tumors, non-T1c tumors with preoperative PSA levels below 4 ng/ml, and non-T1c tumors with PSA levels equal to or greater than 4 ng/ml. These subsets were compared for differences in the distribution of tumor volume, pathologic stage, and Gleason score. An arbitrarily constructed categorization model was used to assess clinical significance. In all, 17 (33%) of the patients had clinical stage T1c disease. In our categorization mode, 88% of the T1c tumors fit the criteria for clinically significant tumors. T1c tumors, however, were significantly smaller (P < 0.01) and were more likely to be organ-confined (P = 0.01) as compared with non-T1c tumors in patients with an elevated preoperative serum PSA level. In contrast, tumors detected at preoperative PSA levels of < 4 ng/ml had comparably the lowest pathologic stages and tumor volumes in our series. In our categorization model, 42% of these tumors fit the criteria for minimal tumor. This group of radical prostatectomies was therefore most likely to harbor clinically insignificant cancer, a finding that was consistent in two other categorization models derived from earlier reports. T1c tumors comprise a large fraction of the tumors found in population-based screening. As judged by their pathologic characteristics. T1c tumors are clinically significant tumors. The overall low pathologic stage and Gleason score of these tumors make these patients excellent candidates for curative treatment by radical prostatectomy or radiotherapy. In contrast, some concern should be raised on the detection of tumors at low serum PSA levels by means of digital rectal examination and transrectal ultrasound alone, since a substantial proportion of these tumors could be considered clinically insignificant. Long-term follow-up, however, is necessary to substantiate this view.

Prostate cancer screening and management

Several other newer therapeutic modalities are being investigated to determine their potential role in the treatment of prostate cancer. Cryotherapy, microwave hyperthermia, laser therapy, and high-intensity focused ultrasound have all been introduced in recent years. Each of these techniques is based on a different principle, yet they all attempt to kill prostate cancer cells in a minimally invasive manner. Insufficient follow-up data are available to allow strong recommendations regarding these treatments.