Transperineal versus transrectal prostate biopsy for predicting the final laterality of prostate cancer: are they reliable enough to select patients for focal therapy? Results from a multicenter international study

OBJECTIVES

To compare the concordance of prostate cancer (PCa) laterality between the extended transperineal (TP) or transrectal (TR) prostate biopsy (BP) and radical prostatectomy (RP) specimens. To identify predictors of laterality agreement between BP and RP.

MATERIALS AND METHODS

Data from 533 consecutive patients with PCa (278 TP and 255 TR-diagnosed) treated with RP were analyzed. A 12-core technique was used for both TP and TR biopsies. Additional cores were obtained when necessary.

RESULTS

Overall, the percentage of agreement of PCa laterality between BP and RP was 60% (K = 0.27, p < 0.001). However, the RP confirmation of unilaterality at BP was obtained in just 33% of the cases. Considering the concordance on bilaterality as the ″target″ of our analysis, the sensitivity and specificity were 54.3% and 98.2% , respectively, with TP and 47.5% and 92.5%, respectively with TR. Focusing on patients with unilaterality at biopsy, none of the evaluated preoperative variables (biopsy technique, age, total positive biopsy cores, PSA, prostate volume, Gleason score on biopsy) were able to predict RP bilaterality in the multivariate analyses.

CONCLUSIONS

Most of the patients with unilateral involvement at BP harbored bilateral PCa after RP. TR and TP biopsy showed no difference in their capacity to predict the concordance of tumor laterality at RP. None of the preoperative evaluated variables can predict the tumor laterality at RP. Using BP unilaterality to include patients in focal therapy (FT) protocols may hinder the oncologic efficacy of FT.

[Sildenafil assumption and acute effects on the uroflowmetric parameters]

AIM

In the recent literature, great attention has been given to the evaluation of the real effectiveness of the phosphodiesterase type 5 inhibitors (PDE-5i), usually prescribed for the erectile dysfunction (ED), in the treatment of the lower urinary tracts symptoms (LUTS). The aim of this study was the evaluation of the acute effects of sildenafil on the uroflowmetric parameters.

METHODS

Within September 2011 and February 2012, twenty-seven patients, affected by ED with a IIEF-5 score ≤21 and a contextual IPSS within 8 e 19, have been selected and enrolled in this study. Two uroflowmetric measurements with suprapubic ultrasound valuation of the post voiding residual (PVR) were performed on each patient, 2 hours before and after the administration of sildenafil (50 mg).

RESULTS

The average age of the patients came out within di 47.3±9.4 years. On the baseline, the average of the Qmax registered has been 15.6±3.3 mL/s, the average Qave has been 8.2±3.2 mL/s and the average resulted 32.5±11.4 mL. After the mono-administration of sildenafil 50 mg, the average Qmax value, the Qave one and the RPM one turned out into 17.7±5.1 mL/s, 10.1±3.5 mL/s and 22.6±9.6 mL. The differences within the standard values, were considered statistically relevant (P<0.05).

CONCLUSIONS

Actually, the study shows that, in the acute phase, the administration of sildenafil 50 mg leads to effects on the uroflowmetric standards on men affected by LUTS and DE.

Hepsin in the diagnosis of prostate cancer

AIM

In the current study we verified whether the expression of hepsin in prostate cancer (PCa) of samples obtained from radical retropubic prostatectomies (RRP) was significantly different from the adjacent normal prostatic tissue. METHODS. We evaluate the expression of hepsin by using immunohistochemistry in PCa tissue in respect to the adjacent normal tissue, of 18 patients who underwent RRP.

RESULTS

Hepsin positive immunoreactivity was estimated on the staining intensity as negative (0), weakly positive (1+), moderately positive (2+), and strongly positive (3+). Hepsin immunoreactivity was detected in 100.0% PCa: 94.4% of cases showed a moderate/strong intensity, 5.6% a weak intensity. The adjacent benign prostatic tissue demonstrated a 83.3% of weak intensity, 11.1% had no reactivity and 5.6% were moderately intense. PCa demonstrated a significant higher (P<0.05) hepsin intensity (2.67) than the adjacent benign tissue (0.94).

CONCLUSION

Hepsin should be regarded as a novel potential immunohistochemical marker for the histopathological diagnosis of PCa.

Current Impact of Transrectal Ultrasonography in Prostate Cancer Diagnosis

Aims

We evaluate the diagnostic accuracy of transrectal prostate ultrasonography (TRUS) in prostate cancer (PCa) diagnosis in a group of patients who underwent prostate biopsy in 2008.

Material and Methods

100 patients (mean age 65 years) underwent transrectal prostate biopsy at our center. Indications to biopsy were: suspected malignancy at rectal examination or increase of total PSA and/or PSA velocity and/or PSA density and/or low percentage of free PSA. 10–12 biopsies and additional ones in case of suspected ecographic images in every patient were carried out. We classified the ecographic aspects as: highly suggestive for heteroplasia (focal or widespread hypoechoic area in the peripheral zone), weakly suggestive (small hypoechoic focal alterations), and isohecoic areas.

Results

At ultrasound examination, highly suggestive images were found in 20 patients, weakly suggestive images in 39 patients, and isoechoic images in 41 patients. PCa was diagnosed in 45 patients. 40% of cancers (18 pts) appeared as highly suggestive hypoechoic images, 31% (14 pts) as weakly suggestive, and 29% (13 pts) as isoechoic. 32% was the positive predictive value of isoechoic areas biopsies, 90% of highly suggestive hypoechoic images, and 36% of weakly suggestive images. In the last ones, the diagnosis was often coincidental, i.e. in the opposite lobe, or in a different sextant of the same lobe (serendipity). Detection rate was 60% for prostate volumes ≤50 cc and 24% for volumes >50 cc.

Discussion

The result analysis allowed us to formulate the following considerations: - 60% of currently diagnosed PCa are not detectable by ultrasonography, or there are aspecific ecographic findings - 40% of cancers are detectable by ultrasonography with specific ecographic findings - The clinical value of the hypoechoic focal alterations is similar to isoechoic ones - Detection rate is positively influenced by prostate volume.

Conclusions

The study of hypoechoic and isoechoic bioptised areas shows a significant difference in TRUS accuracy in prostate cancer diagnosis. In this set of patients, prostate volume and transrectal ultrasonographic findings proved to be the most informative variables about PCa risk at the moment of first biopsy at any age.

Molecular aspects of gefitinib antiproliferative and pro-apoptotic effects in PTEN-positive and PTEN-negative prostate cancer cell lines

To date, no effective therapeutic treatment allows abrogation of the progression of prostate cancer (PCa) to more invasive forms. One of the major targets for the therapy in PCa can be epidermal growth factor receptor (EGFR), which signals via the phosphoinositide 3'-kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK) pathways, among others. Despite multiple reports of overexpression in PCa, the reliance on activated EGFR and its downstream signalling to the PI3K and/or MAPK/extracellular signal-regulated kinase (ERK) pathways has not been fully elucidated. We reported that the EGFR-selective tyrosine kinase inhibitor gefitinib (ZD1839; Iressa) is able to induce growth inhibition, G(1) arrest and apoptosis in PCa cells and that its effectiveness is associated primarily with phosphatase and tensin homologue deleted from chromosome 10 (PTEN) expression (and thus Akt activity). In fact PTEN-negative PCa cells are slowly sensitive to gefitinib treatment, because this molecule is unable to downregulate PI3K/Akt activity. PI3K inhibition, by LY294002 or after PTEN transfection, restores EGFR-stimulated Akt signalling and sensitizes the cells to pro-apoptotic action of gefitinib. The MAPK pathway seems to be involved primarily on cell-growth modulation because dual blockade of EGFR and ERK1/2 phosphorylation potentiates growth inhibition (both not cell apoptosis) in PTEN-positive PCa cells and reduced EGF-mediated growth in PTEN-negative cells. Thus the effectiveness of gefitinib requires growth factor receptor-stimulated PI3K/Akt and MAPK signalling to be intact and functional. The loss of the PTEN activity leads to uncoupling of this signalling pathway, determining a partial gefitinib resistance. Moreover, gefitinib sensitivity may be maintained in these cells through its inhibitory potential in MAPK/ERK pathway activity, modulating proliferative EGFR-triggered events. Therefore, our data suggest that the inhibition of EGFR signalling can result in a significant growth reduction and in increased apoptosis in EGFR-overexpressing PCa cells with different modalities, which are regulated by PTEN status, and this may have relevance in the clinical setting of PCa.

The Role of 5αR Inhibitors in the Early Growth of Pca Cells

Aim of this study is to investigate the efficacy of Finasteride (MK906), a selective 5α reductase type 2(5αR2) inhibitor, and of MK386, a selective 5α reductase type 1 (5αR1), on the cellular proliferation of primary cell cultures derived from patients with prostatic diseases.

Methods

We evaluated the effects of Finasteride and MK386 in 30 primary cultures obtained from prostatic carcinoma (PCa), 6 from high grade intraepithelial neoplasia (HGPIN) and 10 from benign prostatic hyperplasia (BPH).

Results

Primary cultures require testosterone (T) for optimal growth and both 5αR inhibitors decreased cell proliferation of primary cultures of PCa cells. IC50 values of Finasteride were lower when compared to those of MK386. In particular, Finasteride was more active in cultures derived from Gleason 2–6 PCa, compared to those derived from Gleason 7–10 PCa. On the contrary, we observed higher effectiveness of MK386 in Gleason 7–10 PCa derived cultures compared to those derived from Gleason 2–6 PCa tissues. The growth of PCa primary cultures was down-modulated by MK386 through a direct inhibition of the epithelial 5αR1, whereas the anti-proliferative activity of Finasteride seems to be mediated by stromal cells present in the primary cultures.

Conclusions

We found biological evidence for an important role of 5αR inhibitors in the early growth of PCa cells and for the necessity of combining anti-hormonal treatment for a sustained inhibition of PCa through the inhibition of stromal cell function even in advanced and androgen-resistant tumor progression phases.

New Metastatic Models in Vivo of Prostate Cancer

Experimental prostate cancer bone metastases are difficult to form in vivo, and some typical clinical patterns remain irreproducible. In our work we describe new metastatic models in vivo using different experimental approaches.

Methods

We injected prostate cancer cells in the left cardiac ventricle or in the medullar cavity of tibia of male nude mice.

Results

Mice were monitored by x-ray analysis and 70% of them revealed osteolytic lesions 40 days after heart injection. By scintigraphy and alu-PCR we were able to identify early a higher number of metastatic loci than by x-ray.

Conclusions

Heart and intratibial injection of prostate cancer cells in nude mice may represent a good experimental model to investigate the pathophysiology of bone and bone marrow metastases in vivo.

Gefitinib is Able to Sustain Metastatic Progression

The expression of epidermal growth factor receptor (EGFR) is a distinctive marker in the biologic progression of prostatic carcinoma (PCa). Gefitinib (‘Iressa’) is an orally active EGFR tyrosine kinase inhibitor, and in clinical trials has shown important antitumor activity in tumors expressing EGFR. Our aim was to demonstrate that Gefitinib was also effective in inhibiting the cellular capabilities leading to metastasis formation.

Methods

The inhibitory effect of Gefitinib on the invasive phenotype of PCa cells was tested in vivo by injecting PC3 cells subcutaneously (Xenograft) or into the left ventricle of nude mice and by daily administration of various doses of Gefitinib.

Results

The tumoral growth of xenograft was significantly inhibited by 150mg/kg Gefitinib with a reduction of 40% in tumor weight. Moreover mice receiving tumoral cells intracardially showed a significant reduction in bone metastases when treated with Gefitinib.

Conclusions

Our data demonstrate that EGF is able to sustain not only cellular growth, but also metastatic progression. For this reason the use of Gefitinib as a therapeutic agent may also be indicated in the control of tumor spreading in EGF responsive tumor cells.