Prostatic carcinoma: problems in the interpretation of prostatic biopsies

Diagnostic Accuracy of a Combination of Preoperative 68-Ga Prostate-Specific Membrane Antigen Positron Emission Tomography/Computed Tomography and Multiparametric Magnetic Resonance Imaging in Localized Prostate Cancer

INTRODUCTION

Prostate cancer (PCa) is a common and leading course of cancer-related death in men. Although there are studies on multiparametric magnetic resonance imaging (MpMRI) with good diagnostic results in detecting clinically significant PCa, new methods have been investigated due to the low positive predictive values. In this context, prostate-specific membrane antigen positron emission tomography (PSMA PET) emerges as an alternative imaging method to MpMRI. This study aimed to compare 68Ga PSMA I&T-PET/CT and MpMRI in determining tumor location.

METHODS

Preoperative MpMRI and 68Ga PSMA I&T-PET/CT scans and pathology specimens of patients who underwent radical prostatectomy for PCa at our clinic between 2018 and 2021 were retrospectively evaluated. PSMA I&T-PET/CT, MpMRI, combined imaging were compared for tumor localization according to histopathological data.

RESULTS

In terms of tumor localization, MpMRI demonstrated overall accuracy rates of 75.9% (p kappa [κ] 0.0001* [0.525]). 68Ga PSMA I&T-PET/CT showed 71.5% (p κ 0.0001* [0.438]). For the combined imaging approach, the overall accuracy rate was calculated as 79.2% (p κ 0.0001* [0.576]). Additionally, high diagnostic accuracy was achieved for the combined imaging approach, particularly in the intermediate ISUP group. Moreover, SUVmax was calculated as 6.37.

CONCLUSION

The combined use of 68Ga PSMA I&T-PET/CT and MpMRI has high diagnostic rates. However, the high cost is a significant disadvantage that limits their routine combined use.

Prostate cancer: diagnostic criteria and role of immunohistochemistry

The diagnosis of prostate cancer is based on microscopic criteria. Presently, prostate needle biopsy interpretation can be a challenge for the pathologist due to the increased number of specimens with limited amount of suspicious glands and minimal atypia. It is critical for the pathologist to have an organized methodical approach when considering the morphological features enabling a definitive diagnosis of prostate cancer. Although several diagnostic criteria and supportive features have been advocated, only few findings are absolutely specific and diagnostic of prostate cancer. The diagnosis of prostate cancer relies on a combination of architectural and cytological features that are reviewed in detail herein. Infiltrative growth pattern, prominent nucleoli and lack of basal cells are the most useful diagnostic criteria. Perineural invasion, glomerulation and mucinous fibroplasia are pathognomonic features of prostate cancer, although uncommon on small prostate cancer foci. The role of immunohistochemistry in establishing a diagnosis of limited prostate is addressed.

Survey of clinical and pathological characteristics and outcomes of patients with prostate cancer

INTRODUCTION

The importance of implementation: Prostate cancer is the most common malignancy in men and the second leading cause of cancer death in developed countries. Therefore, further studies about the protests of disease, diagnosis and timely treatment are essential.

STUDY METHOD

In this study, 80 prostate cancer patients admitted to Imam Khomeini Hospital, Urmia in Iran from 2000 to 2008 were reviewed. Patients were studied according to their age, clinical protests, Gleason scoring, positive family history, smoking, type of treatment and post-treatment conditions. Questionnaires were adjusted based on the objectives and the data were extracted from the medical records of patients and the desired results were achieved.

RESULTS

In this study, the most common age group for prostate cancer is older than 60 years (92/5%). The most common type of pathology for prostate cancer is adenocarcinoma that 93.75% of cases are included. Secondary TCC with secondary source is present in 5% and sarcoma in 1.25% of cases. 46.25% of patients with prostate cancer are smokers. The most common clinical symptoms among patients are obstructive symptoms (56.25%), and irritation of the urinary tract (52.81%). Hematuria in 26.25% and urinary incontinence in 5% of cases have been recorded. 16.3% of patients referred with metastatic symptoms. Most patients with prostate cancer have Gleason score 5-7 (40%). All patients were undergoing prostatectomy (82.5% TURP and 17.5% SPP) and 47.5% of cases were bilateral orchiectomy. The cases reviewed, 22 were followed that included 27.5% of cases. Among them, 6 people have died due prostate cancer (27.27%) that the mean age of the patients after diagnosis until death was 34.4 months. 2 others died from other causes (9.09%). The remaining 14 cases were elder patients with a mean follow-up duration of 44 months.

CONCLUSION

According to the results obtained in the present study, the most common type of prostate cancer pathology is adenocarcinoma that is included 93.75% of cases. Prostate sarcoma is present at 1.25% and secondary bladder TCC at 5% of cases more over the incidence of prostate sarcoma is reported in a lower age group than adenocarcinoma, which the results obtained in a similar study in Iran in other centers. Regarding the relationship between smoking and prostate cancer it can be considered one of the important factors in this regard. 

Disorders related with ageing in the gerbil female prostate (Skene's paraurethral glands)

The female organs, which are regulated by steroid hormones, are targets of studies especially those related to senescence. However, although the female prostate is an organ influenced by hormones and susceptible to lesions, there is still little information about its histopathology. Thus, given the morphophysiological similarity between the prostate in women and female gerbils, the present study aimed to identify the spontaneous histopathological changes in this rodent to provide contributions to the understanding of lesions that also affect the human female prostate. The structural, ultrastructural, immunohistochemical, morphometric-stereological and serological aspects, as well as the quantification of the incidence, multiplicity and percentage of acini affected by different lesions were analyzed. Benign prostate lesions including hyperplasia, prostatitis, microcalculi and calculi; preneoplastic lesions like dysplasias; premalignant lesions, such as high grade prostatic intraepithelial neoplasia as well as malignant ones, specifically adenocarcinoma, were identified in the adult gland, but they were intensified during senescence, which is possibly due to the imbalance among steroid hormone levels. Although clinical attention focuses on other urogenital organs, the real condition of the histopathological injuries in the human female prostate should be considered. A serious preventive work regarding the female prostate could be applied in the gynaecological context in order to monitor the gland and avoid possible disturbances to women's health and consequently provide better quality of life.

Cell proliferation and apoptosis in prostate tumors and adjacent non-malignant prostate tissue in patients at different time-points after castration treatment

BACKGROUND

Androgen ablation is the standard treatment for advanced prostate cancer but the short-term cellular effects are largely unknown.

METHODS

Sextant prostate biopsies were taken from 77 prostate cancer patients before and 1-10 days after castration treatment. Apoptosis, cell proliferation, and morphology were studied in malignant and non-malignant tissue, using stereological and immunohistochemical methods.

RESULTS

Epithelial cell proliferation was significantly decreased both in non-malignant and malignant epithelium already 1 day after therapy. It remained low until day 7, but increased thereafter in the remaining non-malignant epithelial cells and in some tumors. Epithelial cell apoptosis was significantly increased during the first week and then returned to basal levels. The maximal apoptotic indexes, seven- and two-times the intact levels in the non-malignant and malignant glands, respectively, were found at days 3-4 or even earlier in the tumors. Signs of tumor shrinkage such as glandular collapse and decreased tumor cell size were observed from day 3 in most tumors.

DISCUSSION

The present study shows that the magnitude and kinetics of the response to castration in the normal human prostate is very similar to the response previously described in rodents. We also demonstrate that most human prostate tumors rapidly respond to castration indicating the need for further evaluation of when and how to best monitor the effects of hormone ablation therapy in prostate cancer patients.

[Incidence and significance of "atypical acinar proliferation" in transrectal prostatic biopsies]

OBJECTIVE

To determine the incidence of atypical acini in our series, the percentage of prostate cancer and other suspicious or preneoplastic lesions in the successive biopsies and to establish a follow up strategy in these patients.

MATERIAL AND METHOD

A total of 117 patients diagnosed with isolated atypical acini or associated with high grade PIN were obtained from our database, 75 (64%) of these were submitted to at least a second biopsy of the gland. The age, PSA, digital rectal examination (DRE), prostate volume, ultrasound nodule and previous pathological diagnosis were compared with the pathology results of the successive biopsies of the gland.

RESULTS

Incidence of atypical acini was 4%. A total of 46.7% of patients undergoing a repeat biopsy presented prostate cancer. We did not find significant differences in the clinical variables studied between patients with or without a definite cancer diagnosis. Patients initially diagnosed with acinar atypia with associated high grade PIN presented a higher incidence of cancer in the repeat biopsy than patients with isolated acinar atypia (p=0.007). A total of 94.3% of all neoplasms diagnosed were detected in the 2nd and 3rd biopsy.

CONCLUSIONS

Patients with atypical acini are at high risk of having prostate cancer not detected in the first biopsy. They should, therefore, undergo a second biopsy as soon as possible. There is only a very small probability of detecting cancer after the 3rd biopsy.

MUC6 is a marker of seminal vesicle-ejaculatory duct epithelium and is useful for the differential diagnosis with prostate adenocarcinoma

The diagnosis of prostate adenocarcinoma is usually made on needle biopsies. Numerous benign lesions may mimic malignancy, especially when the focus of carcinoma is limited. The presence of seminal vesicle-ejaculatory duct epithelium on prostate biopsy is not rare and could cause confusion with adenocarcinoma. Lipochrome pigments are frequently encountered in seminal vesicle-ejaculatory duct but may be also seen in prostate adenocarcinoma. Prostate specific antigen immunostaining in difficult cases is sometimes used, but high-grade adenocarcinomas may be negative. In one previous report, MUC6 was found to be expressed in seminal vesicle but not in normal prostate. MUC6 belongs to the family of human mucin genes. So we investigated herein the immunohistochemical expression of MUC6 in prostate adenocarcinomas and seminal vesicle-ejaculatory duct. We have tested 30 prostate adenocarcinomas of various grade, 10 normal seminal vesicles, and 10 prostate adenocarcinomas invading the seminal vesicles. The tissues were fixed in 10% buffered formalin and embedded in paraffin. Immunohistochemistry was performed using the avidin-biotin-peroxidase complex technique. All adenocarcinomas and normal prostate structures tested were negative. In contrast, all seminal vesicles were diffusely immunostained with MUC6 antibody. We concluded that MUC6 is a valuable marker of seminal vesicle-ejaculatory duct and is useful for the differential diagnosis with prostate adenocarcinoma.

Prostate Cancer - Old Problems and New Approaches. (Part II. Diagnostic and Prognostic Markers, Pathology and Biological Aspects)

Diagnostic and prognostic markers for prostatic cancer (PCa) include conventional protein markers (e.g., PAP, PSA, PSMA, PIP, OA-519, Ki-67, PCNA, TF, collagenase, and TIMP 1), angiogenesis indicator (e.g., factor VIII), neuroendocrine differentiation status, adhesion molecules (E-cadherin, integrin), bone matrix degrading products (e.g., ICPT), as well as molecular markers (e.g., PSA, PSMA, p53, 12-LOX, and MSI). Currently, only PSA is used clinically for early diagnosis and monitoring of PCa. The histological differential diagnosis of prostatic adenocarcinoma includes normal tissues such as Cowper's gland, paraganglion tissue and seminal vesicle or ejaculatory duct as well as pathological conditions such as atypical adenomatous hyperplasia, atrophy, basal cell hyperplasia and sclerosing adenosis. A common PCa is characterized by a remarkable heterogeneity in terms of its differentiation, microscopic growth patterns and biological aggressiveness. Most PCa are multifocal with signi ficant variations in tumor grade between anatomically separated tumor foci. The Gleason grading system which recognizes five major grades defined by patterns of neoplastic growth has gained almost uniform acceptance. In predicting the biologic behavior of PCa clinical and pathological stages are used as the major prognostic indicators. Among the cell proliferation and death regulators androgens are critical survival factors for normal prostate epithelial cells as well as for the androgen-dependent human prostatic cancer cells. The androgen ablation has been shown to increase the apoptotic index in prostatic cancer patients and castration also promotes apoptotic death of human prostate carcinoma grown in mice. The progression of PCa, similarly to other malignancies, is a multistep process, accompanied by genetic and epigenetic changes, involving phenomenons as adhesion, invasion and angiogenesis (without prostate specific features).

The presence of atypical small acinar proliferation in prostate needle biopsy is predictive of carcinoma on subsequent biopsy

OBJECTIVE

To determine the clinical significance of nondiagnostic small acini showing cellular atypia (atypical small acinar proliferation) in prostatic biopsies of patients with clinical findings suggestive of malignancy.

PATIENTS AND METHODS

Of 331 patients who underwent thin-core biopsy of the prostate over a 30-month period, 21 (6.3%) had atypical histological features, and of these 17 underwent repeat biopsy. In addition, a further 20 patients with normal histology underwent repeat biopsy for persistent abnormal clinical findings. The incidence and Gleason score of carcinomas subsequently diagnosed in the two groups were compared. The predictive significance of patient age, prostate specific antigen (PSA) level and digital rectal examination (DRE) findings were compared between both patient groups, those in each group subsequently found to have carcinoma, and between patients with malignant or normal repeat biopsies who had either atypical or normal initial biopsies.

RESULTS

Nine patients with atypical histology and four with normal histology on initial biopsy were found to have carcinoma on subsequent biopsy (P = 0.036). The site of carcinoma diagnosed in the repeat biopsy frequently differed from that of the initial atypical biopsy. The Gleason primary pattern was not significantly different between the groups. Neither patient age, PSA level nor DRE findings differed between patients with initial normal or atypical biopsy, or in these groups for those in whom carcinoma was subsequently diagnosed. These clinical features did not distinguish between those with carcinoma or normal findings on repeat biopsy who had an initial atypical biopsy, while only PSA level varied significantly in patients with normal or malignant repeat biopsy in the group with an initial normal biopsy.

CONCLUSION

The presence of atypia on initial biopsy is a strong predictor of malignancy in subsequent biopsy specimens.

Analysis and sorting of prostate cancer cell types by flow cytometry

BACKGROUND

Prostate tumor heterogeneity as manifested by differential expression of markers can be attributed to multiple types of cancer cells populating a tumor. Does the composition differ between primary tumor and metastasis? How can one isolate the different cancer cell types to study? What is the relationship among cancer cell types?

METHODS

Flow cytometry keying on the prostate epithelial cell surface markers CD57 and CD44 was applied to analyze and sort single cells prepared from tumor tissue samples by collagenase digestion. In normal tissue, CD57 is found on luminal cells and CD44 on basal cells.

RESULTS

CD57(+) and CD44(+) cells were sorted from various prostate tumor tissue specimens. The CD57(+) cancer cell type was found to predominate in primary tumors, while the CD44(+) cancer cell type was found to predominate in two visceral metastases. All tumors could be characterized by a ratio of CD57(+) and CD44(+) cancer cells.

CONCLUSIONS

Two types of prostate cancer cells, CD57(+) and CD44(+), were identified. The finding that most primary tumors contain a predominantly CD57(+) cancer cell population agrees with the argument that cancer cells arise from the transformation of CD57(+) luminal cells. However, CD44(+) cancer cells are also present in some primary tumors; and in some metastases, they, and not CD57(+) cells, constitute a predominant population.

Cells in various benign and malignant conditions of the human prostate express different antigenic phenotypes

Prostatic epithelium basically consists of secretory-luminal, basal and endocrine-paracrine cells. Immunohistochemical procedures are frequently used for showing the cells reflecting different differentiations. In this study, 40 prostatic tissue specimens submitted to the Department of Pathology of Inönü University, Research Hospital, between 1991 and 1996 were examined. Half of the cases were diagnosed as cancer and the other half had various benign lesions. Of the cases 22.5% (n = 9) were needle biopsy material whereas the remainder, 47.5% (n = 19), were from prostatectomy and 30% (n = 12) were transurethral resection of the prostate (TURP) specimens. High molecular weight anti-cytokeratin antibodies (HMW anti-cytokeratin) stained basal cells both in all normal prostatic tissue and benign prostatic lesions, but in the majority of cancers (70%, n = 14) negative immunoreactivity was seen. Nevertheless, in some of the cancer cases (30%, n = 6) basal cell anti-cytokeratin staining was shown. Negative immunoreactivity with HMW anti-cytokeratin is important in distinguishing between malignant and benign lesions, whereas positive staining is not every time in favour of benign lesions. With the usage of prostate specific antigen (PSA) it was seen that all of the malignant and benign prostatic lesions stained positively. Basal cells in hyperplastic glands were not stained with this stain. Irregular, and in some areas, intense (PSA) immunoreactivity is present in precancerous and malignant lesions. Endocrine cells, which are represented with Chromogranin-A (Chr-A) immunoreactivity and reflecting neuroendocrine differentiation, are present in 75% (n = 15) of benign lesions and in 50% (n = 10) of cancer cases. It was thought that the lesser number of these cells in neoplastic lesions in comparison to the non-tumoral lesions is correlated with the disorder of mechanism that regulates the cell growth. Both in neoplastic and non-tumoral tissues the prostatic epithelial cells showed the three markers, namely HMW anti-cytokeratin, PSA, and Chr-A, which may reflect the multidirectional differentiation of these cells from a pluripotent origin.

Clinicopathological characteristics of prostatic adenocarcinoma in men with atypical prostate needle biopsies

PURPOSE

Atypical or nondefinitive diagnoses comprise 1.5 to 10% of all prostate needle biopsies and many men with atypical biopsy have carcinoma on rebiopsy. We characterize the clinical and pathological features of these men and the tumors, and compare them to those of other men who had more than 1 biopsy.

MATERIALS AND METHODS

All prostate needle biopsies done at our institution between 1989 and 1996 on men with a followup biopsy were reviewed and the clinicopathological features were correlated.

RESULTS

A total of 343 men had more than 1 biopsy during this period. Of the biopsies 64 were atypical and followup (repeat biopsy) was available for 59. Men with an atypical diagnosis were more likely to have carcinoma (34%) and to be diagnosed subsequently earlier (270 days) than those with an initial negative diagnosis (22%, 603 days). No significant differences were noted in patient age, results of digital rectal examination, initial or followup serum prostate specific antigen, subsequently identified tumor size or Gleason score on needle biopsy or at resection. Although on review as many as 38% of the original atypical foci could be reclassified, this reclassification did not significantly change the results of rebiopsy.

CONCLUSIONS

Men with an atypical diagnosis on prostate biopsy are significantly more likely to have carcinoma on rebiopsy than men with an initial negative diagnosis, and the second biopsy should be performed at a significantly shorter interval. The tumors that are subsequently identified in these men are similar to those identified in men without an atypical biopsy.

Neutral and acid mucins and eosinophil and argyrophil crystalloids in carcinoma and atypical adenomatous hyperplasia of the prostate

Neutral and acid mucins and eosinophil and argyrophil crystalloids were studied in the glandular intraluminal contents of 130 prostatic carcinomas (PCa) and 22 atypical adenomatous hyperplasias (AAH). Specimens were studied in the usual extension for diagnostic purposes and considered positive when minimal amounts of mucin or any crystalloid were present. Some amount of altered secretion was seen in 110 PCa (84.6%) and in 17 AAH (77.3%); the similarity of the figures speaks for the close relationship of these lesions. The relative incidences in PCa/AAH were 61.5%/77.3% for neutral mucin, 80%/54.5% for acid mucin (p < 0.01), 25.4%/50% for eosinophil crystalloids (p < 0.02), 44.6%/9.1% for argyrophil crystalloids (p < 0.01) and 57%/36% for a compound secretion. The incidence of eosinophil crystalloids was greater in AAH and inversely proportional to the Gleason grade in PCa. The incidence of acid mucins and argyrophil crystalloids was higher in PCa and directly proportional to the tumour grade in all but the poorly differentiated ones. It is therefore suggested that AAH positive for acid mucins or argyrophil crystalloids be classified in the high grade AAH group.

The diagnosis and reporting of adenocarcinoma of the prostate in core needle biopsy specimens

BACKGROUND

There has been relatively little written on the diagnosis and reporting of adenocarcinoma of the prostate diagnosed in core needle biopsy specimens.

METHODS

This article reviews issues concerning diagnosing, grading, and quantification of prostate carcinoma in core needle biopsy specimens.

RESULTS

The diagnosis of prostate carcinoma in core needle biopsy specimens is discussed, including the relative frequency and utility of various architecture, cytologic, and ancillary features. Grading of prostate carcinoma in core needle biopsy specimens is evaluated along with the relationship of core needle biopsy grade to corresponding radical prostatectomy grade. The relationship between the extent of carcinoma in core needle biopsy specimens to extent of tumor in the radical prostatectomy is summarized. Finally, this article summarizes articles supporting the use of high molecular weight cytokeratin in the diagnosis of adenocarcinoma of the prostate in core needle biopsy specimens.

CONCLUSIONS

Pathologists are not only called upon to diagnose limited cancer in core needle biopsy specimens, but also to quantify and grade these cancers accurately. Issues relating to this pathologic evaluation are critical for physicians treating men with adenocarcinoma of the prostate.

Characterization of prostatic basal cell hyperplasia and neoplasia in aged macaques: comparative pathology in human and nonhuman primates

There are very few reports of proliferative prostatic lesions occurring spontaneously in nonhuman primates. We found that 15 of 19 glands in aged macaques contained one or more epithelial lesions in the cranial lobe. These originated in the basal cell compartment and were characterized as hyperplasia and benign neoplasia. The adenomas contained variable gland formation, with morphologic and immunohistochemical evidence of secretory, mucigenous, neuroendocrine, transitional, and squamous cell differentiation. These cell types are resident in the normal prostate or appear in metaplastic lesions, and their presence in the macaque tumors is consistent with differentiation of a stem cell along multiple phenotypic pathways. The macaque growths are similar to human prostatic basal cell lesions and could provide insights into their pathogenesis as well as cellular ontogeny and general mechanisms of carcinogenesis in this organ.

Microvascular invasion of the seminal vesicles in adenocarcinoma of the prostate

The objective of this article is to determine the relationship between microvascular invasion and seminal vesicle invasion in prostatic adenocarcinoma. Radical prostatectomies with seminal vesicle involvement were examined histologically and immunohistochemically with antibodies directed against S-100 protein and factor VIII. Microvascular invasion of the seminal vesicles showed a positive correlation with microvascular and capsular invasion of the prostate (P = 0.006 and 0.048, respectively) and lymph node metastases. Tumor progression was found in 8 of 14 (57%) patients with microvascular invasion of the seminal vesicles, compared with 3 of 22 (14%) without microvascular invasion (P = 0.001). Microvascular invasion of the seminal vesicles is predictive of tumor progression and lymph node metastases in prostatic adenocarcinoma.

Prostatic carcinoma with abundant xanthomatous cytoplasm. Foamy gland carcinoma

Foamy gland carcinoma, an unusual variant of prostate carcinoma, is characterized by abundant xanthomatous cytoplasm. We studied 38 needle biopsies in which at least one core contained cancer with >20% foamy morphology. On average, each cancer was 72% foamy, and 11 cancers were entirely foamy. In addition to the characteristic cytoplasm, 20 cases had abundant intraluminal dense pink amorphous secretions. Nuclear enlargement and prominent nucleoli were either absent of rare in 23 (61%) and 27 (71%) of foamy gland carcinomas, respectively. High-molecular-weight cyto-keratin stains were done in 20 cases; 19 foamy gland carcinomas were negative, confirming the diagnosis of carcinoma and one case had keratin staining inconsistent with a known benign pattern. Of the 27 cases with associated ordinary gland carcinoma on needle biopsy, 26 (96%) were Gleason sum greater than 4. Subsequent radical prostatectomy (RP) and transurethral resection demonstrating cancer were available in 17 cases. Of the 15 subsequent RPs, only five were organ-confined and only one was Gleason sum less than 5. The cancers in the RP group ranged from 1 to 90% foamy (mean, 39%). Foamy gland carcinoma must be recognized as carcinoma by its abundant foamy cytoplasm, its architectural pattern of crowded or infiltrative glands, and frequently present pink acellular secretions. The more typical features of adenocarcinoma, nuclear enlargement and prominent nucleoli, are frequently absent. Its relatively benign cytology makes this lesion difficult to recognize as carcinoma; 74% of our cases were seen in consultation. Despite its benign cytology, foamy gland carcinoma is best classified as intermediate-grade carcinoma.

Ki67 labelling index: an independent predictor of progression in prostate cancer treated by radical prostatectomy

The clinical course of prostate cancer is highly variable and cannot satisfactorily be predicted by histological criteria alone. Both tumour cell proliferation and neuroendocrine differentiation have been suggested as additional prognostic parameters, neuroendocrine differentiation being considered to enhance tumour cell proliferation. This study investigated the prognostic value of tumour cell proliferation [Ki67 labelling index (LI), MIB 1] and neuroendocrine differentiation and their relationship to each other. One hundred and thirty-seven paraffin-embedded radical prostatectomy specimens were examined. Neuroendocrine differentiation was found in 58 per cent of cases, but was not associated with pTN stage, Gleason score, Ki67 LI, or tumour progression. Ki67 LI was not significantly associated with pTN stage or with Gleason score. High grade (P = 0.0005), advanced local stage (P = 0.0004), positive lymph nodes (P = 0.02), and high Ki67 LI (P = 0.0203) were predictors of tumour progression if univariate analysis was performed, but Cox stepwise regression showed that only advanced local stage (P = 0.0025) and Ki67 LI (P = 0.0105) were independent predictors of tumour progression, the relative risk being 3.6 and 2.5, respectively. It is concluded that Ki67 is an important prognostic marker in prostate cancer with a potential for routine application.

The alpha 6 beta 1 and alpha 6 beta 4 integrins in human prostate cancer progression

Prostatic secretions are formed by glands composed of basal and luminal cells and surrounded by a basal lamina. The normal basal cells express several integrins (extracellular matrix receptors) including alpha 2, 3, 4, 5, 6, v, beta 1 and beta 4. These integrin units are polarized at the base of the cells adjacent to the basal lamina. The integrin alpha 6 beta 4 is associated with hemidesmosomal-like structures. The natural history of prostate cancer involves the presence of prostatic intraepithelial neoplasia (PIN) lesions (considered precursor lesions), carcinoma in situ and invasive carcinoma. Hemidesmosomal proteins and the alpha 3 beta 1 and alpha 6 beta 1 integrins (laminin receptors) are retained in the early PIN lesions. Expression of the integrins alpha 2, alpha 4, alpha 5, alpha v and beta 4 is lost in carcinoma. The alpha 3 beta 1 and alpha 6 beta 1 integrins remain associated with invasive carcinoma, the latter being predominant. Integrin expression in carcinoma is diffuse in the plasma membrane and not restricted to the basal aspects of the cell. The alpha 6 beta 1 integrin is fully functional as judged by an ability to adhere to laminin and contains the wild type alpha 6A cytoplasmic signaling domain. The alpha 6 beta 1 integrin is a leading candidate for conferring the invasive phenotype in prostatic carcinoma. Tumor cells with high expression of alpha 6 integrin are more invasive when tested in a SCID mouse model system. Following intraperitoneal injection, the human tumor cells invade the mouse diaphragm and move through the muscle on the surface of the laminin coated muscle cells. Our current working hypothesis is that the production of alpha 6 beta 1 and laminin in human tumor cells contributes to the invasive phenotype. Invasion could occur on the surfaces of laminin coated structures such as the nerves, blood vessels or muscle and account for the known patterns of human prostate tumor progression. Blockage of the expression or function of alpha 6 beta 1 or laminin or preventing the loss of beta 4 would be essential steps in confining the carcinoma to the prostate gland where conventional treatment has already proven effective.

Immunohistochemical localization of cathepsin B in neoplastic human prostate

Cathepsin B (CB) has been shown to degrade extracellular matrix (ECM) proteins, and has been reported to be involved in invasion and metastasis of several types of solid organ tumors in human and animals, but CB has not been studied in human prostate cancer (CAP). Our objective was to determine the CB protein immunostaining pattern in CAP and to correlate the immunostaining with the degree of malignancy as reflected in the Gleason grading system. We used two types of CB antibodies (namely, monospecific, polyclonal antibodies to human liver CB prepared in rabbits, and polyclonal antibody produced in sheep) to establish CB localization patterns in neoplastic prostate. Our analysis showed a heterogeneous CB immunostaining pattern in the neoplastic human prostate. CB immunostaining occurred in many, but not all, of the neoplastic columnar/cuboidal cells of acini and isolated cells, i.e., in small ragged glands and clusters (groups) of invasive cells in the prostatic stroma. We have shown that, in general, there was a positive correlation of the intensity of CB immunostaining with the Gleason histologic score (or Gleason grade sum) tumors, i.e., from the lowest scores through score 8, but many of the tumors with scores 9 and 10 showed little CB immunostaining. Our study indicated that the increased CB immunostaining in the Gleason grade sum 5-8 tumors may be associated with increased degradation of ECM, but not in 9 and 10 despite the fact that the latter tumors are more malignant clinically. In well-differentiated tumors, fewer CB immunostaining cells were present than the moderately-differentiated tumors. In other words, most of the stromal invasion of the prostatic ECM occurred in tumors of Gleason grade sums 5-8. We suggest that CB immunostaining might be a useful method to assess stromal invasion of prostatic carcinoma, especially in the higher grade tumors.

Diagnostic criteria of limited adenocarcinoma of the prostate on needle biopsy

Over a period of 25 weeks 434 needle biopsy specimens of the prostate were sent to the author for consultation because of diagnostic concerns. The final diagnoses were cancer (69%), benign (13%), atypical but not diagnostic (10%), high grade prostatic intraepithelial neoplasia (PIN) (5%), and miscellaneous (3%). The most common benign entities mimicking cancer were atrophy (29 specimens) and adenosis (19 specimens). The 300 cancer specimens were analyzed further. Architecturally, the presence of small glands between larger benign glands was the most common pattern seen in 80% of carcinomas; haphazard growth patterns, single cells, and cribriform glands were seen less frequently. The following diagnostic features were helpful: nuclear enlargement (77% of specimens); prominent nucleoli (76%); pink acellular intraluminal secretions (53%); amphophilic cytoplasm (39%); blue-tinged mucinous secretions (34%); crystalloids (25%); PIN (13%); mitotic figures (11%); and perineural invasion (3%). The mean and median numbers of malignant glands in this series were 31 and 20, respectively (range, two to 300). Tumors with a Gleason score lower than 6 caused greater diagnostic problems for referring physicians because these tumors had a greater number of malignant glands, yet were still sent in for consultation (P = .0018). Gleason score was positively correlated with prominent nucleoli and amphophilic cytoplasm and inversely correlated with the presence of crystalloids. Prominent nucleoli, which often are quoted as being essential for the diagnosis of prostate cancer, were not seen in 24% of the specimens and seen only rarely in another 25%. The diagnosis of prostate cancer is based on a constellation of features. Even in this series with a limited number of malignant glands, 85% of specimens contained three or more of the above-listed diagnostic features in addition to architectural atypia.

Proliferating cell nuclear antigen/cyclin in incidental carcinoma of the prostate

Monoclonal antibody to proliferating cell nuclear antigen (PCNA) has been used to identify the growth fraction in ten cases of benign prostatic hyperplasia (BPH), in 20 prostatic microcarcinomas (PMC) and in 30 cases of infiltrating prostatic carcinoma (PC). Ten year follow-up was available on all cases by means of clinical, serological, radiological and echographic examinations. The percentage of PCNA-staining nuclei was independently counted by two observers. Statistical analysis showed significant differences between PCNA/cyclin score of BPH and PMC without recurrences with respect to those of PMC with progression and of PC. PCNA immunostaining may represent a reliable method for assessing cellular proliferative activity. It may be used as a more powerful diagnostic hallmark of PMC than patterns of non-malignant microglandular proliferation and is also a useful additional test for assigning histological grades to PMC and PC. Statistical analysis indicated that PCNA/cyclin index was an independent significant prognostic indicator of predicting malignant progression (P < or = 0.01) and survival rates (P < or = 0.05) of PC and PMC (> 5 mm diameter).

The frequency of carcinoma and intraepithelial neoplasia of the prostate in young male patients

The incidence of clinically detected prostate cancer is increasing with more frequent diagnosis in younger male patients. Whether this represents a genuine increase in incidence or earlier detection is not clear. To understand better the evolution and early changes of prostate cancer we evaluated 152 prostate glands from young male patients 10 to 49 years old. Of the prostates 98 were from African-Americans and 54 were from white patients. Prostatic intraepithelial neoplasia was identified in 0%, 9%, 20 and 44%, and small foci of histological cancer in 0%, 0%, 27% and 34% of the male patients in the second, third, fourth and fifth decades of age, respectively. The majority of the cases of prostatic intraepithelial neoplasia were of low grade. High grade prostatic intraepithelial neoplasia, found in 5 prostates, was first identified in the fifth decade. All 5 cases occurred in prostates containing histological carcinoma. Incidental carcinoma was detected with a similar frequency in white and black patients. The cancerous foci were of similar size with a tendency for cancer in black patients to be multifocal, particularly in those in the fifth decade. We conclude that prostatic intraepithelial neoplasia and histological cancers are surprisingly common in young male patients of both races. The evolution of prostatic intraepithelial neoplasia and focal histological cancers is not clear but it appears to present several decades earlier than clinically detected carcinoma. The natural history of prostate cancer must encompass many more years (decades) than has been previously realized. In addition, the initiating events leading to clinically relevant prostate cancers likely occur at a remarkably young age.

Nucleoli in low-grade prostate adenocarcinoma and adenosis

This study compares the frequency of prominent nucleoli in low-grade adenocarcinoma with that of its frequent mimicker, adenosis. One hundred thirteen transurethral resection specimens of stage A purely low-grade adenocarcinoma (only Gleason score 1 or 2) were evaluated. Eighteen cases of adenosis were evaluated for comparison. Prominent nucleoli were defined as those with a greatest dimension more than 1.6 microns as measured with an ocular micrometer. The frequency of prominent nucleoli in each focus was estimated as (1) none, (2) rare (< 5% of epithelial cells), (3) occasional (5% to 50% of epithelial cells), and (4) frequent (> 50% of epithelial cells). Twenty percent of cases of adenocarcinoma had, at most, rare prominent nucleoli. Eight percent of adenocarcinoma cases had no prominent nucleoli. Twenty-eight percent of cases of adenosis had at least one focus of occasional or frequent prominent nucleoli. We conclude that a small but significant subset of low-grade prostatic adenocarcinomas lack prominent nucleoli and, likewise, a significant proportion of cases of adenosis have prominent nucleoli. Like many other histologic features of these lesions, we feel there is a spectrum of frequency of prominent nucleoli, with overlap between the two. The significance of nucleoli should be taken in context with other cytologic and architectural features characteristic of prostatic adenocarcinoma and adenosis. In difficult cases basal cell-specific immunohistochemical stains may be helpful.

A pathologist's view of prostatic carcinoma

In this article, the pathologic findings of carcinoma of the prostate were reviewed. Criteria were discussed for the pathologic diagnosis of prostatic carcinoma (PC), premalignant lesions, lesions that simulate PC, immunopathologic findings, special types of PC, effects of therapy on the prostate, and recent efforts to improve diagnostic and prognostic capabilities. The possible role of the study of nucleolar organizing regions was reported. A new method for demonstrating chromosomes in formaldehyde-fixed paraffin-embedded tissue was mentioned. The need for research in all aspects of the pathology of prostatic cancer was emphasized.

Localization of a biotinylated cathepsin B oligonucleotide probe in human prostate including invasive cells and invasive edges by in situ hybridization

The cysteine endopeptidase cathepsin B (CB) can degrade basement membrane (BM) proteins (such as laminin, type IV collagen, and fibronectin) at both acid and neutral pHs suggesting that CB has a role in tumor invasion and distant metastasis. The distribution and intensity of CB protein localization vary in normal prostate, benign prostatic hyperplasia (BPH), and neoplastic prostate. These considerations have led us to examine whether the distribution of CB localization in malignant and normal cells is due to storage or active synthesis of CB. In the present study, we examined the localization patterns of CB at the mRNA level in normal prostate, BPH, and well to moderately differentiated neoplastic prostate, focusing on invasive groups of cells and invasive edges of malignant tumors. We used a 25-base biotinylated oligonucleotide CB cDNA "sense" probe to localize CB message in prostate samples obtained from radical prostatectomies. We have determined that CB is actively synthesized by the epithelia of normal, hyperplastic, and neoplastic prostate including some invasive cells in the invasive edges. In both normal and BPH, CB mRNA was localized predominantly in acinar basal cells with some localization in cuboidal/columnar cells. In contrast, in neoplastic prostate, CB mRNA was localized predominantly in columnar cells and in groups of invasive cells and invasive edges. Thus, in malignant prostate the predominant cell types expressing CB differed from those of the normal prostate and BPH. Analysis of CB mRNA localizations indicated a heterogeneity in staining distribution in prostate cancer with some invasive groups of cells and invasive edges exhibiting CB mRNA and others exhibiting little or no reaction products.(ABSTRACT TRUNCATED AT 250 WORDS)