Treatment changes in prostatic hyperplasia and cancer, including androgen deprivation therapy and radiotherapy

High-intensity focused ultrasound for the treatment of prostate cancer: assessing location of failure after focal therapy in prostate cancer and review of histological characteristics and clinicopathologic correlates after treatment-a 5-year experience

High-intensity focused ultrasound (HIFU) is a noninvasive treatment option used for localized prostate cancer or salvage surgery after failed radiation therapy. Histological changes in post-treatment needle biopsies are reviewed to better understand HIFU failures. Between 2016 and 2021, 50 patients with localized prostate cancer were enrolled and treated in this study. Of these, 10 patients underwent salvage therapy after radiation failure and 7 did not have post-treatment needle biopsies available for review and were excluded. Inclusion criteria included pathologically confirmed prostate cancer and clinical stage T1/T2 disease. We describe the histological changes in post-treatment needle biopsies as part of routine follow-up. Biopsies were examined for presence, distribution and extent of residual adenocarcinoma, Gleason score, and ablative tissue changes. A total of 33 patients underwent HIFU hemi-ablation treatment of localized prostate cancer as primary treatment with post-treatment biopsies available for review. The average mean age of the patients was 64 years (range, 52-81 years). The average PSA (prostate-specific antigen) level of the patients was 6.3 ng/mL (range, 2.4-14.7 ng/mL). The Gleason scores assigned in pretreatment prostate needle biopsies are as follows: 3 + 3 (1 case, 3%), 3 + 4 (21 cases, 64%), 4 + 3 (9 cases, 27%), and 4 + 4 (2 cases, 6%). In post-treatment needle biopsies, 33 cases (100%) showed variable degrees of fibrosis ranging from mild to moderate. Twenty-four of 33 cases (73%) showed necrosis usually associated with acute and/or chronic inflammation. Histological examination of benign glands revealed glandular heterogeneity including atrophy and basal cell hyperplasia. Eight cases (24%) had residual prostatic adenocarcinoma after treatment, of which 4 cases were assigned Gleason score: ≥3 + 4. In cases with residual adenocarcinoma, 8 cases (100%) showed nuclear enlargement, 5 cases (63%), cytoplasmic vacuolization, and 1 case (13%) showed nuclear pyknosis; otherwise, no discernible effects of treatment were seen. Morphological alterations included a spectrum of changes ranging from extensive coagulative stromal necrosis secondary to thermal injury to atrophic changes in benign prostatic tissue after HIFU treatment. Our findings also support the hypothesis that HIFU failure results from inadequate targeting rather than failure within a treated zone.

Computer vision detects subtle histological effects of dutasteride on benign prostate

OBJECTIVE

To determine whether a computer vision-based approach applied to haematoxylin and eosin (H&E) prostate biopsy images can distinguish dutasteride-treated tissue from placebo, and identify features associated with degree of responsiveness to 5α-reductase inhibitor (5ARI) therapy.

SUBJECTS AND METHODS

Our study population comprised 100 treatment-adherent men without prostate cancer assigned to dutasteride or placebo in the REDUCE trial, who had slides available from mandatory year-4 biopsies. Half of the men also provided slides from a year-2 biopsy. We obtained 20× whole-slide images and used specialized software to generate a library of 1 300 epithelial and stromal features from objects comprising superpixels and several types of nuclei, including spatial relations among objects between and within each hierarchical level. We used penalized logistic regression and fivefold cross-validation to find optimal combinations of histological features in the year-4 biopsies. Feature data from the year-2 biopsies were fitted to a final model for independent validation. Two pathologists, blinded to treatment, scored each image for focal atrophy and histological features previously linked to 5AR1 treatment.

RESULTS

Consensus classification by pathologists obtained a discrimination accuracy equivalent to chance. A 21-feature computer vision model gave a cross-validation area under the curve of 0.97 (95% confidence interval [CI] 0.95-0.99) in the year-4 biopsies and 0.79 (95% CI: 0.65-0.92) in the set-aside year-2 biopsies. Histology scores were not correlated with change in prostate-specific antigen level, serum dihydrotestosterone level or gland volume. Key features associated with dutasteride treatment included greater shape and colour uniformity in stroma, irregular clustering of epithelial nuclei, and greater variation in lumen shape.

CONCLUSION

The present findings show that a computer vision approach can detect subtle histological effects attributable to dutasteride, resulting in a continuous measure of responsiveness to the drug that could eventually be used to predict individual patient response in the context of BPH treatment or cancer chemoprevention.

Five-alpha reductase inhibitor influences expression of androgen receptor and HOXB13 in human hyperplastic prostate tissue

OBJECTIVES

Five-alpha reductase inhibitors (5ARIs) are known as chemopreventive agents in prostate cancer with a risk of high-grade disease. This study evaluated the effects of 5ARI on androgen receptor (AR) and proteins involved in prostate cell growth such as HOXB13 expression in human prostate tissue and LNCaP prostate cancer cells.

MATERIALS AND METHODS

We retrospectively selected 21 patients who underwent TURP between March 2007 and February 2010 for previously confirmed BPH by prostate biopsy. They were grouped into control (group 1, n = 9) and 5ARI treatment (group 2, n = 12) before TURP. AR and HOXB13 expression in prostate tissue was evaluated by immunohistochemical staining. We tested the effect of 5ARI on the expression of AR, prostate specific antigen (PSA) and HOXB13 in LNCaP cells. Cells were assessed by Western blot analysis, MTT in vitro proliferation assay, and ELISA.

RESULTS

Group 2 showed stronger reactivity for AR and HOXB13 than those of the group 1. MTT assay showed death of LNCaP cells at 25uM of 5ARI. At the same time, ELISA assay for PSA showed that 5ARI inhibited secretion of PSA in LNCaP cells. Western blot analysis showed that 5ARI did not greatly alter AR expression but it stimulated the expression of HOXB13.

CONCLUSIONS

These results demonstrated that 5ARI influences AR and HOXB13 expression in both LNCaP cells and human prostate tissue. In order to use 5ARI in chemoprevention of prostate cancer, we still need to clarify the influence of 5ARI in ARs and oncogenic proteins and its regulation pathway.

Precursors of prostate cancer

High-grade prostatic intraepithelial neoplasia (PIN) is the only accepted precursor of prostatic adenocarcinoma, according to numerous studies of animal models and man; other proposed precursors include atrophy and malignancy-associated changes (with no morphologic changes). PIN is characterized by progressive abnormalities of phenotype and genotype that are intermediate between benign prostatic epithelium and cancer, indicating impairment of cell differentiation and regulatory control with advancing stages of prostatic carcinogenesis. The only method of detection of PIN is biopsy because it does not significantly elevate serum prostate-specific antigen concentration and cannot be detected by ultrasonography. The mean incidence of PIN in biopsies is 9% (range, 4%-16%), representing about 115,000 new cases of isolated PIN diagnosed each year in the United States. The clinical importance of PIN is its high predictive value as a marker for adenocarcinoma, and its identification warrants repeat biopsy for concurrent or subsequent carcinoma, especially when multifocal or observed in association with atypical small acinar proliferation (ASAP). Carcinoma develops in most patients with PIN within 10 years. Androgen deprivation therapy and radiation therapy decrease the prevalence and extent of PIN, suggesting that these forms of treatment may play a role in prevention of subsequent cancer. Multiple clinical trials to date of men with PIN have had modest success in delaying or preventing subsequent cancer.

Finasteride upregulates expression of androgen receptor in hyperplastic prostate and LNCaP cells: implications for chemoprevention of prostate cancer

BACKGROUND

Although finasteride is recognized for its role as a chemopreventive agent for prostate cancer, higher grades of malignancy have been reported. It is questioned whether blocking of testosterone conversion to dihydrotestosterone (DHT) by finasteride in prostate tissue will change expression of androgen receptor (AR). Therefore, this study evaluated the effects of finasteride on AR expression in prostate tissue and in the LNCaP cell line.

METHODS

Between January and December 2006, we retrospectively selected and evaluated 47 cases of benign prostatic hyperplasia treated with variable duration of finasteride (5 mg QD) before transurethral resection of the prostate. AR expression in prostate tissue was semiquantified by immunostaining and compared with duration of finasteride treatment. An androgen-dependent prostate cancer cell line (LNCaP) was cultured in charcoal/dextran-treated FBS with DHT or testosterone, and treated with finasteride for 1-3 weeks. Samples of total RNA were collected to analyze expression of AR by real-time quantitative reverse transcription polymerase chain reaction.

RESULTS

Immunohistochemical study revealed significant upregulation of ARs by finasteride treatment for 30-180 days. In cell line study, quantitative real-time reverse transcription polymerase chain reaction revealed significant upregulation of ARs treated by finasteride.

CONCLUSIONS

In our study, finasteride influenced AR expression in benign prostate tissue and prostate cancer cell. Before we can use finasteride in chemoprevention with confidence, we still need to clarify the influence of finasteride in ARs and its regulation pathway.

Histopathological findings after treatment of prostate cancer using high-intensity focused ultrasound (HIFU)

BACKGROUND

High-intensity focused ultrasound (HIFU) treatment is a novel minimally invasive therapeutic option for patients with localized prostate cancer. Little is known about the histological findings in prostate biopsies upon HIFU treatment.

METHOD

We examined the spectrum of histological changes in prostate biopsies of 25 prostate cancer patients who were previously treated with HIFU. The biopsies were taken 180 days after HIFU treatment.

RESULTS

Seventy-two percent of the cases showed necrosis, often accompanied by acute, chronic, or granulomatous inflammation. Mild or moderate fibrosis was present in all biopsies. In benign glands, histological examination revealed a heterogeneous cellular damage and cellular response including cytologic atypia and basal cell hyperplasia. Eleven patients (44%) had residual prostatic carcinoma after treatment. In cases with residual adenocarcinoma, the majority of the cases (9/11, 88%) do no have apparent treatment effects. Two cases showed nuclear pyknosis. In summary, we report the histological findings in benign and malignant prostatic tissues after HIFU treatment. These findings include a spectrum of morphological changes ranging from apparent necrosis to more subtle cellular damage can be observed in benign prostatic tissue after HIFU treatment. There were minimal morphologic changes in residual adenocarcinoma after HIFU treatments.

CONCLUSION

The pathologist should be aware of common histologic findings in prostatic biopsies after HIFU treatment. We recommend routine reporting of Gleason scores in post-HIFU needle biopsies.

[Histological modifications observed in prostate after preserving treatments for prostate cancer and their impact on Gleason score interpretation]

Total prostatectomy remains the main treatment for intermediate risk prostate cancer with a life expectancy greater than 10 years. In other cases non-surgical treatments can be proposed: external radiotherapy (exclusive or combined anti-androgen therapy), brachytherapy with permanent implants, high frequency ultrasounds (HIFU, Ablatherm), cryotherapy or exclusive hormonal treatment. For such patients in case of biological recurrence, prostate biopsies are usually performed in order to affirm the local recurrence. The histological confirmation of persistent tumor is usually required before any treatment: salvage surgery, cryotherapy, and brachytherapy or high intensity focused ultrasound (HIFU). Pathologists must be aware of the histological modifications induced by these different treatments in order to ensure an optimal interpretation of the biopsies. In this review, we describe the modifications observed in the normal prostate and in cancers after these various therapeutic methods, and also after alpha reductase inhibitors proposed as treatment of benign prostate hypertrophy and prostate cancer chemoprevention.

A subset of prostate basal cells lacks the expression of corresponding phenotypic markers

Immunohistochemical staining for cytokeratin (CK) 34ssE12 has been routinely used to elucidate prostate basal cells for differentiation between non-invasive and invasive lesions. Our previous studies, however, revealed that some morphologically distinct basal cells observed on H&E-stained sections completely lacked CK34ssE12 expression. Our current study attempted to assess whether these basal cells would also lack the expression of other phenotypic markers, and whether basal cell alterations would affect the proliferation status of the associated tumor cells. Consecutive sections from prostate tumors with large basal cell clusters that were morphologically distinct in H&E sections but were completely negative for CK 34ssE12 were morphologically and immunohistochemically assessed with a panel of basal cell phenotypic and other markers. In addition to CK 34ssE12, these basal cells also completely lacked the expression of other phenotypic markers, including CK5, CK14, p63, and maspin, in contrast to adjacent basal cells, which were strongly positive for these markers. Tumors surrounded by basal cell layers that lack the expression of basal cell phenotypic markers showed a significantly higher rate of cell proliferation and mast cell infiltration than their counterparts. These findings suggest that basal cells might be targets of a variety of pathological alterations, which could significantly impact biological presentations of associated tumor cells.

Pathological changes of high-grade prostatic intraepithelial neoplasia and prostate cancer after monotherapy with bicalutamide 150 mg

OBJECTIVES

To evaluate the morphological changes induced by a 3-month course of neoadjuvant bicalutamide 150 mg/day before radical prostatectomy (RP) on prostatic adenocarcinoma and high-grade prostatic intraepithelial neoplasia (HGPIN).

PATIENTS AND METHODS

In all, 90 patients with cT1-T2 prostate cancer and HGPIN on prostatic biopsy were randomized to receive bicalutamide (150 mg/day for 3 months) before RP, or to have immediate surgery. Surgical specimens were assessed for the histopathological features of cancer, HGPIN and benign epithelium in a blinded manner. The volumes of prostate cancer and HGPIN were evaluated using a stereological (i.e. grid) method.

RESULTS

Compared with the bicalutamide-treated group, the ratio of stroma to epithelium, evaluated by visual microscopic assessment in the normal epithelium of the three prostate zones, was significantly lower in the control group, at 2.27 (sd 1.13), than in the treated group, at 1.87 (sd 0.72) (P = 0.048). The mean (sd) tumour volume was significantly lower in the bicalutamide-treated than in the control group, at 0.914 (0.13) vs 1.47 (0.24) mL (P = 0.044). Similarly, the mean (sd) volume of HGPIN was significantly lower in the bicalutamide-treated than in the control group, at 0.34 (0.06) vs 0.62 (0.07) mL (P = 0.003). At RP, specimen Gleason scores in the bicalutamide-treated group were similar to those in the control group, and were no different from the biopsy Gleason scores.

CONCLUSIONS

Involution and epithelial shrinkage of prostate cancer and HGPIN were evident after neoadjuvant treatment with bicalutamide 150 mg. There was no evidence of the emergence of higher-grade cancer after treatment.

Effects of long-term finasteride treatment on prostate cancer morphology and clinical outcome

OBJECTIVES

To examine the morphologic alterations of finasteride therapy on prostate cancer compared with no treatment or treatment with a luteinizing hormone-releasing hormone (LHRH) agonist and the clinical outcomes of patients treated with finasteride.

METHODS

The data of 56 patients with prostate cancer who had taken finasteride for at least 6 months were reviewed. A central pathology review was performed in a blinded manner comparing these patients with 56 matched controls and 44 patients who received a 3-month course of LHRH agonist before radical prostatectomy. The histologic hormonal treatment effects included apoptosis, vacuolated cytoplasm, pyknotic nuclei, and small irregular glands. An overall consensus was scored using a three-tiered system: no apparent effect (score = 0), suspicious for hormonal effect (score = 1), and highly suggestive of hormonal treatment (score = 2). A Gleason score was assigned to all prostatectomy specimens.

RESULTS

The mean hormonal treatment score for the prostatectomy specimens was 0.4, 0.5, and 1.6 for the control, finasteride, and 3-month LHRH groups, respectively. Surprisingly, 20% of control patients had suspicious or highly suggestive hormonal effects and 26% of the finasteride-treated patients did so. For the LHRH-treated group, only 23% did not demonstrate classic features of hormonal treatment. Similar clinical outcomes were observed between the finasteride and control groups.

CONCLUSIONS

No consistent hormonal therapy effects with finasteride treatment were observed compared with LHRH agonists. The hormonal effect was observed in the control group. Therefore, although other aspects of the Prostate Cancer Prevention Trial design might account for the greater percentage of Gleason grade tumors in the study arm, morphologic changes due to long-term finasteride treatment were not a likely cause.

The finasteride prostate cancer prevention trial (PCPT) – What have we learned?

In 2003, the first of two large NCI-sponsored prostate cancer chemoprevention trials was reported. The prostate cancer prevention trial (PCPT) demonstrated a 24.8% reduction in the prevalence of prostate cancer in men taking finasteride 5mg/d for 7 years. However, despite the overall reduced risk of prostate cancer, men in the finasteride-treated arm of the study were more likely to develop high-grade disease. This article examines some of the controversies aroused by the PCPT and evaluates some of the arguments that have been advanced in an attempt to explain some of the unexpected outcomes of the study. In addition, some of the recent studies assessing the potential impact of an effective chemopreventive strategy on population mortality are reviewed. To conclude, there is some discussion of factors, which need to be openly discussed with male patients who might be considered for finasteride therapy.

Gleason grade remains an important prognostic predictor in men diagnosed with prostate cancer while on finasteride therapy

OBJECTIVE

To evaluate men treated with finasteride for lower urinary tract symptoms, who subsequently were diagnosed with prostate cancer and had a radical prostatectomy (RP) at our institution, to determine if finasteride therapy prevented accurate Gleason grade assignment and prediction of biochemical recurrence.

PATIENTS AND METHODS

Between May 1996 and July 2003, 45 men were identified who had RP and had previously been treated with finasteride for > or = 6 months before the diagnosis of prostate cancer. Clinical and pathological information was gathered from a RP database. Serum prostate-specific antigen (PSA) level, duration of finasteride therapy, biopsy Gleason grade, clinical stage, RP Gleason grade and pathological stage were reviewed. Freedom from recurrence was predicted using validated nomograms before and after RP, and compared against actuarial 5-year freedom from recurrence using the Kaplan-Meier method. RESULTS The mean duration of finasteride therapy before diagnosis was 23.6 months, the mean serum PSA (doubled to account for finasteride use) 11.02 ng/mL and mean biopsy Gleason score 6. When comparing the biopsy and RP specimen Gleason score, it was downgraded by 1 point in six men, upgraded by 1 point in eight, and upgraded by 2 points in one. The Gleason score was constant in 30 patients. The nomograms predicted freedom from recurrence in 83% and 85%, respectively; the 5-year actuarial freedom from recurrence was 86%.

CONCLUSION

Finasteride does not appear to compromise the assignment of Gleason grade for use in prediction tools before or after RP in men undergoing prostate biopsy or RP. The actuarial 5-year freedom from recurrence was similar to that predicted by the validated nomograms. Gleason grade remains an important prognostic predictor in men treated with finasteride and undergoing RP for clinically localized prostate cancer.

Therapieinduzierte Tumorregression des Prostatakarzinoms

Regressive changes following pretreatment of prostate cancer may represent a big challenge for the histopathologist not familiar with the assessment of pretreated specimens. Characteristic changes after antiandrogen therapy in non-malignant prostate tissue include glandular atrophy, basal cell prominence and/or basal cell hyperplasia as well as a hypercellular stroma. Morphologic changes in prostate cancer include cytoplasmic clearing and vacuolization, nuclear pyknosis and even complete cell destruction. On the glandular level, changes are characterized by various degrees of involutional changes, ranging from almost non-regressive tumor glands to complete glandular disruption with scattered isolated tumor cells dispersed in the stroma. Knowledge about these changes, the selective use of immunohistochemistry as well as a very thorough histological workup is essential for the correct assessment of these specimens.

Distinguishing atrophy and high-grade prostatic intraepithelial neoplasia from prostatic adenocarcinoma with and without previous adjuvant hormone therapy with the aid of cytokeratin 5/6

We evaluated the sensitivity and specificity of cytokeratin (CK) 5/6 for distinguishing foci of atrophy from prostatic adenocarcinoma with and without previous hormonal adjuvant therapy and observed the intensity and pattern of staining in mimickers of prostatic adenocarcinoma (basal cell hyperplasia, atypical adenomatous hyperplasia, and tangentially cut high-grade prostatic intraepithelial neoplasia [PIN]). We reviewed 146 acinar proliferations in 81 specimens (radical prostatectomy, previously untreated, 41; radical prostatectomy, following androgen-deprivation therapy, 11; transurethral resection, previously untreated, 29). All benign acinar proliferations stained positively for CK5/6, with immunoreactivity restricted to basal cells. Untreated and androgen-deprived prostatic adenocarcinomas were invariably negative. The pattern of staining was continuous in 79% of the atrophy cases (15/19), and all foci stained with CK5/6. Characteristic double-layer staining in basal cell hyperplasia was observed in 93% of cases (13/14), and foci of high-grade PIN had a characteristic "checkerboard" staining with areas of discontinuity. Foci of atypical adenomatous hyperplasia showed continuous staining, including cauterized acini in 53% of cases (8/15), with a fragmented basal cell layer pattern in 47% of cases (7/15). CK5/6 staining of the basal cells in foci of atrophy is sensitive and specific for excluding prostatic adenocarcinoma with and without androgen-deprivation effect.