Deoxyribonucleic acid ploidy status as no basis for pathologic stage prediction in clinically resectable prostate cancer

[Cell ploidy: predictive factor of locally advanced prostate cancer]

OBJECTIVE

This study was designed to demonstrate that the study of cell ploidy on biopsies of clinically localized prostate cancers can contribute to the diagnosis of a tumour extending beyond the prostatic capsule and can complete imaging for local staging.

METHODS

Analysis of the histological results of 140 patients operated for clinically localized prostate cancer distinguished two groups of patients in whom the initial tumour was Gleason score 6 or 7. The first group was composed of 33 patients whose tumour was classified as pT3 and the second group was composed of 24 patients whose tumour was classified as pT2. The cell ploidy study was performed on biopsies and operative specimens in the two groups.

RESULTS

In the pT3N0M0 group, 72% of tumours presented an aneuploid contingent versus 16% of tumours of the pT2N0M0 group. A strong correlation was demonstrated between cell ploidy and tumour stage (p = 0.0002) and a highly significant correlation was observed between tumour stage and the presence of a tumour contingent with ploidy greater than 5C (p = 0.0009).

CONCLUSION

The presence of an aneuploid contingent on biopsies of clinically localized prostate cancer significantly increases the risk of a more advanced tumour. This technique could therefore constitute a simple complementary tool in the staging of prostate cancer in combination with transrectal MRI, but this needs to be confirmed by other studies.

Evaluation of some tissue and serum biomarkers in prostatic carcinoma among Egyptian males

OBJECTIVES

The purpose of this study is to evaluate the role of soluble E-cadherin as a serum marker and bcl-2 and DNA content as tissue markers in characterization and management of prostatic adenocarcinoma (PC) among Egyptian males.

DESIGN AND METHODS

The study group included 71 patients with prostatic adenocarcinoma, 30 patients with benign prostatic hyperplasia (BPH), and 20 normal male subjects. Serum soluble E-cadherin (sE-cadherin) and PSA were quantified by ELISA and MEIA (microparticle enzyme immunoassay) techniques, respectively. Tissue samples were investigated for bcl-2 chromosomal translocation t(14;18) by polymerase chain reaction (PCR) together with detection of bcl-2 protein expression by immunohistochemistry. The results were correlated with DNA content (as defined by flow cytometric analysis) and also with traditional clinicopathologic parameters.

RESULTS

Our data revealed that, serum PSA was superior to sE-cadherin as a marker for PC with a sensitivity of 83% compared to 59% in case of E-cadherin at the same specificity (96.6%). Combination of both markers raised the sensitivity to 90%. E-cadherin correlated with Gleason score. Ploidy status, synthetic phase fraction (SPF), and proliferation index (PI) correlated significantly with tumor Gleason score. PI was also correlated to clinical stage. bcl-2 protein was overexpressed in 14% of PC and it showed a trend for correlation with tumor Gleason score (p = 0.06). We failed to detect chromosomal t(14;18) in the bcl-2 gene in all the studied tumors.

CONCLUSIONS

E-Cadherin is a clinically useful biomarker in PC specially in combination with PSA. DNA content changes and bcl-2 oncogene may account for tumorogenesis and may assist in prognostication of PC.

Predictability of PSA failure in prostate cancer by computerized cytometric assessment of tumoral cell proliferation

OBJECTIVES

To evaluate the relationship of DNA ploidy and cell proliferation (CP) with Gleason score (GS) and clinical outcome in prostate cancer.

METHODS

Sixteen patients with benign prostatic hyperplasia (BPH) and 65 patients with prostate cancer classified by GS (four groups: 2 to 4, 5 to 6, 7, and 8 to 10) were studied. All patients with carcinoma underwent prostatectomy and were separated into prostate-specific antigen (PSA) failure and nonfailure groups (failure if PSA 0.1 ng/mL or more three times after surgery). Tumoral CP (Ki-67 inmunostaining and SG2M phase) and DNA ploidy were evaluated by computerized cytometry.

RESULTS

BPH were diploid with low CP (8% SG2M cells or less). Carcinomas were either diploid with high CP (greater than 8% SG2M cells) or aneuploid. CP was significantly higher (P <0.001) in tumors with GS 7 or greater than in tumors with GS less than 7 (mean percent Ki-67 cells 18.3% versus 7.8%, respectively). PSA failure increased with GS (7.1% in GS 2 to 4, 21% in GS 5 to 6, 28.6% in GS 7, and 50% in GS 8 to 10), as well as with aneuploidy (18.5% in diploid tumors versus 72.7% in aneuploid tumors). Those experiencing PSA failure had significantly higher (P <0.001) CP than those not failing (mean percent Ki-67 cells 24% and mean percent SG2M 30.4% versus 8.7% and 13.5%, respectively). Cox regression analysis showed GS, DNA ploidy, Ki-67, and SG2M to each be univariately prognostic for time to PSA failure; however, Ki-67 and SG2M were more highly significant (P <0.0001 for both) than GS (P = 0.007) or DNA ploidy (P = 0.002). After adjusting for either SG2M or Ki-67 measures of CP, neither ploidy nor GS contained additional prognostic value.

CONCLUSIONS

Tumor CP and DNA ploidy can be reliably determined in prostate cancer by computerized cytometry. On the basis of our preliminary results, CP correlates well with GS and predicts PSA failure better than DNA ploidy or GS.

DNA ploidy and survival of patients with clinically localized prostate cancer treated without intent to cure

BACKGROUND

The optimal approach to diagnosis and treatment of localized prostate cancer remains controversial. Deoxyribonucleic acid (DNA) ploidy has been suggested as an important predictor for outcome in prostate cancer. The purpose of this study was to correlate DNA ploidy with disease-specific survival in patients with clinically localized prostate cancer treated with no intent to cure.

METHODS

DNA ploidy was determined by flow cytometry in archival formalin fixed, paraffin embedded tumor tissue obtained at diagnosis in 120 patients with clinically localized prostate cancer with a nearly complete follow-up.

RESULTS

Ninety (75%) of the tumors were diploid, while only 11 (9%) tumors were categorized as tetraploid. Tumor DNA ploidy (diploid versus nondiploid) significantly associated with histopathological grade (P=0.002) and disease-specific survival (P=0.011), while there was no association with tumor stage (P=0.054). In a multivariate Cox analysis, histopathological grade (P=0.005) was the only significant predictor of disease-specific death, while analyzing the 96 low-grade tumors separately, DNA ploidy became significant (P= 0.024).

CONCLUSIONS

Flow cytometric determined nondiploidy was associated with disease-specific death in patients with clinically localized prostate cancer, but DNA ploidy provided additional prognostic information in patients with low-grade tumors only.

Zonal biopsy in the detection of prostate cancer in Japanese men

To reduce sampling error as much as possible in the detection of prostate cancer, extensive transition zone sampling, in addition to the standard sextant random systematic biopsies, has been proposed. Improved biopsy techniques should make possible earlier and more effective detection of prostate cancer in a population where the incidence is low. Evaluation of such biopsies for elderly Japanese males is thus required. A total of 344 Japanese patients participated in this study. They underwent two transition zone biopsies in addition to systematic biopsy. Fifty-five of the 344 patients (16.0%) had cancer. Both biopsies were positive in 33 patients (60.0%), the standard systematic sextant biopsy alone demonstrated cancer in further 20 (36.4%) and the transition zone biopsy alone was positive in two others (3.6%). The two patients with cancer only in the transition zone biopsy cores had palpable abnormality and elevated prostate specific antigen. None of those with palpably benign glands or those with prior negative biopsies had cancer in the transition zone. Two additional cores from the transition zone led to no increase in morbidity of biopsy. Transition zone biopsy would not significantly contribute to the detection of prostate cancer in the present Japanese elderly male population. Though possibly of some value for certain patients, this biopsy does not warrant routine use.

Urinary continence following radical prostatectomy

An examination was made of pre- and postoperative variables for predicting urinary continence following radical prostatectomy in 94 consecutive patients. Postoperative recovery of urinary continence continued for up to 18 months, when it plateaued. No pads were required in 73.0% of the patients at 18 months. The interval until recovery of urinary continence following surgery averaged 4.0 +/- 3.3 months. Clinical stage, pathologic stage, tumor grade, tumor volume, preservation of neurovascular bundles, methods of bladder neck reconstruction, internal urethrotomy for anastomotic stricture and postoperative adjuvant external beam radiation therapy provided no indication of postoperative urinary incontinence. Preoperative endocrine therapy, preoperative prostate-specific antigen level of > or = 10.0 ng/ml and age < 70 years at the time of surgery were all associated with a greater probability of urinary incontinence. Multiple factors are involved in the etiology of postprostatectomy urinary incontinence. In patients who had undergone surgery because of local progression following endocrine therapy associated with a high serum prostate-specific antigen level, a significantly inferior outcome was noted. Stricter criteria for indicating radical prostatectomy in patients with prostate cancer are needed. Surgical techniques should also be improved for better overall continence.