Pathology of carcinoma of the prostate

Disseminated tumor cells in bone marrow following definitive radiotherapy for intermediate or high-risk prostate cancer

BACKGROUND

The purpose of this study was to explore the prevalence of disseminated tumor cells (DTCs) in bone marrow (BM) of clinically progression-free prostate cancer (PC) patients at least 2 years after curatively intended radiotherapy (RT) with or without adjuvant hormone treatment.

METHODS

All patients were T(1-3)N(0)M(0) with intermediate or high risk of progression. Median time from RT to BM sampling was 5 years (2-8). A standardized immunocytochemical method applying the anticytokeratin antibodies AE1/AE3 was used for DTCs detection in 130 patients. Morphological characterization of immunostained cells was performed to exclude false positive cells. The post-treatment BM was explored in relation to pre-treatment risk factors, treatment strategy and serum levels of Testosterone and PSA at the time of BM sampling. Longitudinal changes in BM status were studied in a sub-group of 109 patients who also had donated BM prior to treatment.

RESULTS

Post-treatment BM-aspirates were positive for DTCs in 17% of cases without correlation to any of the tested variables. Out of 14 patients who had DTCs in BM prior to treatment, all but one had become post-treatment negative. Out of 95 patients with pre-treatment negative BM status, 18 (19%) had become post-treatment positive.

CONCLUSIONS

DTCs in BM were found in 17% of clinically progression-free PC patients following RT. The detection of these cells may provide PSA-independent prognostic information remaining to be explored by prolonged follow-up.

A reliable biomarker derived from plasmalogens to evaluate malignancy and metastatic capacity of human cancers

Antigen tumor markers employed in monitoring therapeutical approaches are limited by their specificity (Sp) and sensitivity (Se). The aim of this study was to investigate the suitability of a lipid tumor marker derived from ether-linked phospholipids and to compare it with others usually assayed in clinical practice. Complex lipids from normal and pathological breast, lung, and prostate tissue were isolated and analyzed by TLC and c-GLC methods. Results were compared as pooled samples, or by means of the averaged percent changes with respect to the composition observed in the normal tissue of the same patient. Sp, Se, negative-predictive (NPV) and positive- predictive values (PPV) were established for conventional markers and for the proposed lipid-derived marker. Results demonstrated that the content of monoenoic fatty acyl chains was significantly increased in total lipids, phosphatidylethanolamine, and especially in ethanolamine-containing ether lipids of neoplastic tissues with respect to their corresponding normal ones. Major changes were observed in the plasmalogen sub-fraction where the ratio monoenoic/saturated fatty acids can distinguish with high Se normal tissues from either benign or neoplastic tissues from breast, lung, or prostate lesions. Analyses of fatty acyl chains from ethanolamine-containing plasmalogens provided a reliable tumor marker that correlated with high Se and linearity with metastases spreading. This fact may be useful in prognosis of the most frequently observed human cancers.

10-Year Survival and Quality of Life in Patients With High-Risk PN0 Prostate Cancer Following Definitive Radiotherapy

PURPOSE

To evaluate long-term overall survival (OS), cancer-specific survival (CSS), clinical progression-free survival (cPFS), and health-related quality of life (HRQoL) following definitive radiotherapy (RT) given to T(1-4p)N(0)M(0) prostate cancer patients provided by a single institution between 1989 and 1996.

METHODS AND MATERIALS

We assessed outcome among 203 patients who had completed three-dimensional conformal RT (66 Gy) without hormone treatment and in whom staging by lymphadenectomy had been performed. OS was compared with an age-matched control group from the general population. A cross-sectional, self-report survey of HRQoL was performed among surviving patients.

RESULTS

Median observation time was 10 years (range, 1-16 years). Eighty-one percent had high-risk tumors defined as T(3-4) or Gleason score (GS) > or =7B (4+3). Among these, 10-year OS, CSS, and cPFS rates were 52%, 66%, and 39%, respectively. The corresponding fractions in low-risk patients (T(1-2) and GS < or =7A [3+4]) were 79%, 95%, and 73%, respectively. Both CSS and cPFS were predicted by GS and T-classification; OS was associated with GS only. High-risk, but not low-risk, patients had reduced OS compared with the general population (p < 0.0005). When pelvis-related side effects were included in multivariate analyzes together with physical function and pain, sexual, urinary, and bowel function were not independently associated with self-reported global quality of life.

CONCLUSIONS

Despite surgically proven (p)N(0), RT with dosage <70 Gy as monotherapy does not give satisfactory CSS rates after 10 years in patients with T(3-4) or GS > or =7B.

Penile metastasis from a T1b prostate carcinoma

BACKGROUND

Penile metastasis from incidental prostate carcinoma has not been described to date.

CASE REPORT

The case of a 72-year-old man affected by penile metastasis from incidental prostate carcinoma is described. In March 1998, the patient underwent prostate surgery for lower urinary tract symptoms related to benign prostatic obstruction. Histological examination revealed an incidental adenocarcinoma of the prostate. The pre-operative prostate-specific antigen (PSA) value was 3.6 ng/ml. A prostate biopsy in the peripheral prostate lobes was negative. PSA progressively rose to 8 ng/ml. The prostate biopsy was repeated and was still negative. The patient was subjected to radiotherapy, as a result of which his PSA fell to 0.7 ng/ml. 4 years after prostatectomy, the PSA rose again and the patient underwent hormonal therapy. The PSA fell to < 0.001 ng/ml. In May 2004, the patient reported a painful, erythematous nodule on his penis glans. Surgical biopsy showed a metastasis from prostate adenocarcinoma and he underwent partial penectomy. Due to disease progression, the patient underwent medical therapy. PSA and testosterone were always at minimum levels. 20 months later the patient died.

CONCLUSION

We underline the uncertainty of the biological behaviour and optimal management of incidentally identified prostate carcinoma. In addition, we highlight that biological and clinical progression could be the consequence of inadequate treatment recommendations.

Cancer of the prostate

Prostate carcinoma, with about 190,000 new cases occurring each year (15% of all cancers in men), is the most frequent cancer among men in northern and western Europe. Causes of the disease are essentially unknown, although hormonal factors are involved, and diet may exert an indirect influence; some genes, potentially involved in hereditary prostate cancer (HPC) have been identified. A suspect of prostate cancer may derive from elevated serum prostate-specific antigen (PSA) values and/or a suspicious digital rectal examination (DRE) finding. For a definitive diagnosis, however, a positive prostate biopsy is requested. Treatment strategy is defined according to initial PSA stage, and grade of the disease and age and general conditions of the patient. In localized disease, watchful waiting is indicated as primary option in patients with well or moderately differentiated tumours and a life expectancy <10 years, while radical prostatectomy and radiotherapy (with or without hormone-therapy) could be appropriate choices in the remaining cases. Hormone-therapy is the treatment of choice, combined with radiotherapy, for locally advanced or bulky disease and is effective, but not curative, in 80-85% of the cases of advanced disease. Patients who develop a hormone-refractory prostate cancer disease (HRPC) have to be evaluated for chemotherapy because of the recent demonstration of improved overall survival (2-2.5 months) and quality of life with docetaxel in more than 1,600 cases.

Double-fluorescence image microscopy for quantitation of prostate-specific antigen in histologic sections of the prostate

BACKGROUND

Although the assessment of serum prostate-specific antigen (PSA) has become a powerful instrument in the diagnosis and for prognosis of prostate carcinoma, there are few quantitative studies of PSA in tissue sections.

METHODS

We developed a technique using double-fluorescence image microscopy for quantifying immunohistochemical reactions in tissue sections. PSA was stained by Texas Red and the cellular DNA was counterstained with 4,6-diamidino-2-phenylindole, dihydrochloride (DAPI). The fluorescence of Texas Red and DAPI was quantified separately after subtraction of background and shading correction. The amount of PSA related to the amount of DNA in identical tissue parts was studied in archival specimens from patients with hyperplasia and prostate carcinoma.

RESULTS

The amount of tissue PSA decreased with the increase in tumor grade, Gleason score, and the change from diploid to aneuploid.

CONCLUSION

Double-fluorescence image microscopy is a valuable technique for obtaining quantitative information of cellular constituents. For standardization of immunochemical reactions in tissue sections, cellular DNA seems to be most appropriate.

Bcl-2 correlates with tumor ploidy and nuclear morphology in early stage prostate carcinoma. A fine needle aspiration biopsy study

We evaluated the nuclear morphology, ploidy, bcl-2 expression and in situ apoptosis in sections of fine-needle aspiration (FNA) biopsy specimens of thirty-one randomly selected Stage B prostate carcinomas. Sections of paraffin-embedded pelleted cells obtained from FNA biopsy specimens were studied. Nuclear grade was determined according to the WHO system. Nuclear morphometry and DNA ploidy were carried out using an automated image analyzer. We used immunostaining and the TUNEL method to evaluate bcl-2 expression and in situ apoptosis. The median nuclear area increased with increasing nuclear grade. Ploidy analysis showed that 54.8% of tumors were diploid, 3.2% tetraploid and 41.9% aneuploid. Bcl-2 overexpression was found in 10 of 31 tumors. There was a significant positive correlation between bcl-2 expression and nuclear area (r(s): 0.45 p < 0.01). Nine of ten bcl-2-positive tumors had a nuclear area larger than the median of the series, and 70% of bcl-2-positive tumors were of the aneuploid type. The apoptotic index had a negative correlation with nuclear area, and the lowest indexes were found in aneuploid tumors. Bcl-2 expression showed a highly significant association with both parameters of high aggressiveness: nuclear size and aneuploidy. The combined evaluation of nuclear morphology, ploidy and cell survival parameters might better identify patients with poor prognosis among early stage prostate carcinomas diagnosed by FNA biopsies.

A retrospective analysis of the results of p(65) + Be neutrontherapy for the treatment of prostate adenocarcinoma at the cyclotron of Louvain-la-Neuve. Part I: Survival and progression-free survival

PURPOSE

To retrospectively evaluate survival, progression-free survival (PFS) and biological response in a series of patients irradiated with mixed neutron/photon beams for locally advanced prostate cancer in our institution.

PATIENTS AND METHODS

Three hundred and eight patients were treated between January 1990 and December 1996. Fifty-five of these were recruited for pT3 or pN1 tumors after radical prostatectomy. Neoadjuvant androgen deprivation was given in 106 patients. The treatment protocol consisted of a mixed photon/neutron irradiation in a two-to-three proportion, up to a total equivalent dose of 66 Gy (assuming a clinical RBE value of 2.8). Pre- and post-treatment PSA determinations were available in practically all cases. Study endpoints were overall survival (OAS) and progression-free survival (PFS). The Cox proportional hazard regression model was used to investigate the prognostic value of baseline characteristics on survival and progression-free survival were a progression was defined as local, regional, metastatic or biological progression. Mean age was 69 years (49-86); mean pretreatment PSA was 15 (0.5-330) in all patients and 14 (0.5-160) in those receiving neoadjuvant hormonotherapy; seven patients only had an initial PSA < or = 4 ng/mL; 15% were T1, 46% were T2, 28% were T3 or pT3 and 4% were T4 (7% unspecified); WHO grade of differentiation was I in 38%, II in 38% and III in 14% (5% unspecified).

RESULTS

The median follow-up was 2.8 years (0-7.8). Five-year overall survival (OAS) was 79% (95% CI: 71-87%) and 5-year progression-free survival (PFS) was 64% (95% CI: 54-74%) for the entire series. PFS in patients with an initial PSA > or = 20 ng/mL was the same. PFS could be predicted by two optimal Cox regression models, one including histological grade (p = 0.003) and initial PSA (p = 0.0009) as cofactors, the other including histological grade (p = 0.003) and T stage (p = 0.02). The main prognostic factors for overall survival were PSA and age. Biological responses with PSA < 1.5 ng/mL, < 1 ng/mL and < 0.5 ng/mL at any time after treatment were documented in 70%, 61% and 47% of the patients, respectively.

CONCLUSION

Five-year OAS was 79%, PFS was 64%, and biological response was 70% for prostate cancer patients treated with mixed photon/neutron beams as applied at Louvain-la-Neuve, which are good results as compared with the literature. The usual prognostic factors were confirmed.

Incidental prostatic carcinoma. A predictive role of neoangiogenesis and comparison with other prognostic factors

Incidental prostatic carcinoma (ICP) has good prognosis related to low stage at diagnosis. Few rogressive cases demanding aggressive treatment need early identification. Neoangiogenesis proved its predictive role in prostatic carcinoma after radical prostatectomy. To reveal its value in ICP authors investigated specimens after transurethral resection of prostate (TURP). Retrospective study was performed on 68 ICP diagnosed in years 1985 1989. Microvessels highlighted by factor VIII were counted in a x200 microscope field (0,8012 mm 2 ) in most active areas of neovascularisation. Microvessel count was correlated with tumor differentiation degree, Gleason score, disease stage, and patients survival in at least 9 years after diagnosis. Higher maximal microvessel counts were associated with lower degree of tumor differentiation (p=0,005), Gleason score (p=0,001), and disease stage (0,003). No association with disease progression and patients survival was found. Mean microvessel counts showed less significant values when correlated with tumor differentiation degree (p=0,003) and Gleason score (p=0, 01), and no correlation with other variables. Microvessel density in TURP specimens of ICP retains its prognostic value already demonstrated in carcinoma of peripheral prostatic lobes. Maximal microvessel counts were prognostically more reliable than mean values.

Processing fine needle aspirates of prostate carcinomas for standard immunocytochemical studies and in situ apoptosis detection

A method is described for making permanent histological sections of prostate carcinoma material obtained by fine needle aspiration (FNA) under ecography guidance. Smears made from prostate aspirates were used for diagnosis and from the same patient remaining aspirates were expelled into fixative filled microcentrifuge tube. Aspirates were pelleted and further processed to paraffin blocks. Permanent histological sections were obtained and each section was defined as satisfactory when it contained about 200 intact tumor cells. We have used these tumor sections and immunocytochemistry (ICC) procedures to study molecular biological marker expression. The technique described here has proven to be easy to use and offered a fast, reliable and cost-effective method to obtain suitable samples for standard ICC and in situ apoptosis detection from FNA prostate carcinoma. The method should be equally suitable for outpatient use on other tumors in which FNA and ICC or in situ apoptosis detection is likely to be helpful.

Combined treatment with temporary short-term high dose rate iridium-192 brachytherapy and external beam radiotherapy for irradiation of localized prostatic carcinoma

PURPOSE

To evaluate the treatment outcome after radical radiotherapy of localized prostate cancer in 50 patients (38 patients with stage T1-2 and 12 patients with stage T3) after a median follow-up time of 45 months (range 18-92 months).

METHODS

The treatment was given by combination of external beam radiotherapy (50 Gy) and brachytherapy (2 x 10 Gy). The brachytherapy was given using TRUS-guided percutaneously inserted temporary needles with a high dose rate remote afterloading technique with Ir-192 as the radionuclide source. Three target definitions and dose levels inside the prostate gland were used. Local control was evaluated by digital rectal examination, TRUS-guided biopsies and serum PSA evaluations.

RESULTS

Clinical and biopsy verified local control was achieved in 48 of the 50 (96%) patients; for stage T1-2 in 37 of 38 (97%) patients and for stage T3 in 11 of 12 (92%) patients. A posttreatment serum PSA level < or =1.0 ng/ml was seen in 42 (84%) patients, values from >1.0 to < or =2.0 ng/ml were seen in four (8%) patients and values exceeding 2.0 were seen in four (8%) patients. The late toxicity was minimal.

CONCLUSION

The local control results and the minimal toxicity after the combined radiotherapy treatment are promising. However, long term results are necessary before general use.

Posttreatment biopsy results following interstitial brachytherapy in early-stage prostate cancer

PURPOSE

To assess pathologic control rates for prostatic carcinoma as determined by postimplant prostate biopsy in a large series of consecutive patients who have received permanent interstitial brachytherapy using a contemporary transrectal ultrasound-directed, transperineal, computer generated, volume technique.

METHODS AND MATERIALS

Four hundred and two patients received permanent 125I or 103Pd interstitial brachytherapy as primary treatment for early stage prostatic carcinoma at the Northwest Tumor Institute between January 1988 and January 1994. Of these, 201 have consented to biopsy 12 or more months postimplant with a median follow-up of 40 months (range: 12-83 months). None had received hormonal manipulation. A total of 361 biopsies was performed on 201 patients with a range of one to six annual biopsies per patient (91 received multiple, serial biopsies). Of the 161 patients more than 12 months postimplant who have not been biopsied, most have been unwilling or unable to submit to biopsy. Only six patients with biochemical progression have not been biopsied. There was no difference in the presenting characteristics or implant parameters between those patients biopsied and those that were not. One hundred and forty-three received 125I (71%) prescribed to a MPD of 160 Gy with a median activity of 35.5 mCi, and 58 (29%) received 103Pd prescribed to a MPD of 115 Gy with a median activity of 123 mCi. Multiple biopsies were performed under transrectal ultrasound guidance, and all specimens were classified as either negative, indeterminate, or positive.

RESULTS

At the time of last biopsy, 161 (80%) have achieved negative pathology, 34 (17%) remain indeterminate, and 6 (3%) have been positive. Only 2 of the 186 patients with a PSA < 4.0 ng/ml at the time of biopsy were positive. Among those 33 indeterminate patients with a subsequent biopsy, 28 have converted to negative, 2 to positive, and 3 remain unchanged to date.

CONCLUSIONS

These data demonstrate at least an 80% pathologically confirmed local control rate following permanent interstitial brachytherapy for early stage prostate cancer. A higher local control rate is expected with further follow-up as the majority of indeterminate biopsies convert to negative over time. The indeterminate category of postirradiation biopsy described here includes specimens that have probably been interpreted as positive in other series, but correlate clinically and biochemically with negative biopsies. These results support the use of modern interstitial brachytherapy techniques for selected patients with early stage adenocarcinoma of the prostate.

Signet-ring carcinoma of the prostate

A case of prostatic signet-ring adenocarcinoma is described in a man with a history of open prostatectomy for prostate carcinoma (18 years previously). Immunostaining confirmed the prostatic origin of the signet-ring tumor which stained for prostatic acid phosphatase (PSAP) and prostate specific antigen (PSA). Cytokeratin immunostaining showed the vacuoles to be true lamina with clear and distinct outlines, the feature confirmed by ultrastructural examination. This aggressive tumor is an uncommon but distinct variant of primary prostatic carcinoma which should be distinguished from artefactual vacuolation of tumor, inflammatory and stromal cells, and metastatic disease.

Histological grade heterogeneity in multifocal prostate cancer. Biological and clinical implications

In order to understand the clinical and biological implications of prostate cancer multifocality and heterogeneity, we investigated their occurrence in relation to variables such as tumour volume, local invasion, and biopsy findings. In a series of 61 completely sectioned whole-mount radical prostatectomy specimens with clinical stage T2 prostate cancer, we mapped histological grade heterogeneity and tumour multifocality. We also evaluated 55 prostate biopsy cases to assess the accuracy of pre-operative grading. Among all of the prostates, only 28 per cent had a single tumour and in 16 per cent one histological grade of cancer was evident. Extracapsular invasion was not restricted to the largest tumour in each case, but also occurred in tumours of relatively small volume and low histological grade. Variability of histological grade was directly proportional to tumour volume. Both grade heterogeneity and tumour multifocality of the prostatectomy specimen showed no significant relationship to the grade accuracy of biopsies. Biopsy grading error proved greatest among small, well-differentiated, tumours. Whole-mount sectioning of prostatectomy specimens in patients with clinically localized adenocarcinoma demonstrates that grade heterogeneity is most closely related to tumour volume; that the largest (index) tumour lesion may not be representative of the pathological stage; and that grading error in prostate needle biopsies can be only partly explained by grade heterogeneity or tumour multifocality.

Should brachytherapy be considered a therapeutic option in localized prostate cancer?

Contemporary prostate brachytherapy incorporates advances in computer analysis, imaging technology, and delivery apparatus, allowing exacting and reproducible results compared with historical approaches. The advances permit brachytherapy to be performed on a cost-effective, outpatient basis with low morbidity in the appropriately selected patient. Although unsettled questions remain regarding dosimetric issues, long-term outcomes, and morbidity, the weight of evidence to date appears to support the use of brachytherapy in selected patients. Brachytherapy may be considered a therapeutic option: as monotherapy for early-stage disease and also a boost following moderate doses of external beam irradiation for locally advanced disease.

Incidental Prostatic Carcinoma

Incidental carcinoma of the prostate is defined as an incidentally detected cancer without any clinical manifestation, i.e. latent. Clinically, it is diagnosed mostly by TUR and is staged as T1a and T1b according to the TNM classification. There is clinical understaging, however, of up to 27% for T1a and 68% for T1b. Although the subdivision seems justifiable on the basis of the progression rates (8% and 63% respectively), it is not a useful indicator of the natural history of the incidental carcinoma. Pathological staging of TUR specimens is far from standardized, with regard to both the different sampling methods and the commonly-used classifications. Since the T1 staging system is based more on how the cancer is identified than on classifying its pathology, different methods should be used for a full clinical understanding of an incidental carcinoma. Distinguishing cancers as clinically important or not allows a better prognostic indication compared to the staging systems, which can still not be considered as precise indicators of whether to treat the cancer or wait and see. Unfortunately the true prognostic factors cannot be directly deduced from the currently used sampling methods of TUR specimens. A complete diagnostic assessment should be carried out after initial diagnosis of incidental prostatic cancer in order to appreciate its clinical importance. Basically both revision of the material by the pathologist and further clinical investigation are useful. Lastly, the need for close co-operation between urologists and pathologists should be stressed.

Correlation of pretherapy prostate cancer characteristics with histologic findings from pelvic lymphadenectomy specimens

PURPOSE

The purpose of this study was to identify pretherapy factors associated with pelvic lymph node involvement (LNI) in patients with localized prostatic carcinoma (CaP), and to develop a model that would allow for estimation of this risk at the time of initial diagnosis.

METHODS AND MATERIALS

Between January 1988 and December 1992, 2439 patients with clinical Stage T1a-3cN0-XM0 CaP underwent radical retropubic prostatectomy and bilateral pelvic lymph node dissection as sole initial therapy at a single medical institution. Preoperative factors were evaluated for their association with pelvic LNI in univariate and multivariate logistic regression analysis. A model was developed that incorporated independent predictive variables, and probability plots were generated to estimate the likelihood of pelvic LNI in the patient with a new diagnosis of localized CaP.

RESULTS

Within clinical tumor stage, three groups (Tla-2a, T2b-c, and T3) were identified in which the observed rate of pelvic LNI was distinctly different. Gleason primary grades were also combined (1-2, 3, and 4-5) because of a similar observation. Univariate analysis identified clinical tumor stage (p < 0.0001), Gleason primary grade (p < 0.0001), and serum prostate-specific antigen (p < 0.0001) as factors associated with pelvic LNI. Each of these variables retained independent significance (p < or = 0.0002) in the multivariate model. Patient age (p = 0.12) and history of prior transurethral resection of the prostate (p = 0.36) were not found to correlate with this endpoint. Probability plots provided an estimate of the likelihood for pelvic LNI according to the combination of pretherapy clinical tumor stage, Gleason primary grade, and serum prostate-specific antigen level.

CONCLUSION

Clinical tumor stage as determined by digital rectal examination, Gleason primary grade of the diagnostic biopsy specimen, and pretherapy serum prostate-specific antigen value can be combined to estimate the probability of pelvic LNI for the patient with a new diagnosis of localized CaP. This information may be of value in directing the pretherapy diagnostic evaluation, as an aid in radiation therapy treatment planning, and in the conduct of clinical research efforts.

p53 protein expression as prognostic factor in patients undergoing radical prostatectomy for prostatic cancer

The authors give preliminary data on the evaluation of the p53 protein expression as prognostic factor in patients subjected to radical prostatectomy for prostatic cancer. p53 protein immunohistochemical nuclear staining was carried out on neoplastic tissue obtained from systematic sextant prostatic biopsies at the time of diagnosis. Out of 46 Patients 15 (32%) were p53 positive (p53+). No statistical correlation was observed between P53 staining, preoperative PSA and pathological Gleason Score, while the rate of patients with nodal involvement (pN+) was higher in the p53+ group than the P53- group with low statistical significance (p<0.03). The authors cannot yet evaluate Progression time and survival because the mean follow-up of the patients is still too short (30 months). The study is still in progress.

Prostate cancer screening and prevention: "realities and hope"

Case finding and population screening for early prostate cancer are extensively debated issues. The increasing incidence and mortality of prostate cancer, although largely in older patients, suggests that some type of preventive measures should be undertaken to reverse this trend. The basic requirements for initiation of a population screening program were established by Wilson and Jungner in 1968. Based on available data, the following requirements are considered to be realities in this article: the importance of the health problem, the effectiveness of available treatment, the availability of the facilities, the identification of latent stages of the disease, the existence of effective screening methodology, and the acceptability of screening by the population to be screened. For choice of treatment and the stage of the tumor at the time of diagnosis, the data analysis is positive but caution is advised. Errors of commission and omission do occur in daily practice. The answers to the remaining four requirements are less clear. There is hope--but no certainty--that we are able to predict the natural history of the disease, that early treatment does reduce mortality, that treatment strategies avoid overlap, and that the cost of population screening has been appropriately calculated. The lack of a positive answer to these questions leads us to advise against general screening but to support definitively a randomized screening trial to provide answers in the next decade.

Diagnostic decision support for prostate lesions

The diagnostic evaluation of premalignant and malignant lesions of the prostate may benefit from the application of an inference network. Used as a diagnostic decision support system, an inference network provides standardized assessment of diagnostic clues which is supported by computer graphics and comparison imagery, uncertainty management by possibility and probabilistic schemes and the systematic combination of different pieces of diagnostic evidence. This assessment results in a numeric measure of belief in the final diagnosis.

Differentiation-stage specific expression of oncoprotein 18 in human and rat prostatic adenocarcinoma

Oncoprotein 18 (Op18) is an intracellular phosphoprotein that has been shown to be overexpression in a number of human malignancies. In the present report we have studied the pattern of Op18 expression on normal, hyperplastic, and malignant prostatic tissue as well as in rat prostatic tumor lines. One of the objectives of the present work was to establish whether the level of Op18 expression can be used as a prognostic marker in human prostatic adenocarcinoma. To that end, sections from normal, hyperplastic, and malignant human prostatic tissue were examined by immunohistochemistry for expression of Op18. In the normal and hyperplastic prostate, Op18 expression was observed in basal glandular epithelial cells, whereas the columnar luminal epithelial cells were not stained by the anti Op18 antibodies. In highly differentiated prostatic cancers occasional epithelial cells were stained, while in poorly differentiated tumors most of the epithelial cells contained Op18 immunoreactivity. The staining pattern was similar in the primary prostatic tumor and in the regional lymph node metastases. Most importantly, a limited survey of prostatic cancer patient samples (n = 40) showed a significant correlation between the fraction of Op18 immunoreactive cells and survival. Studies of a rat prostatic tumor model, showed that only a few cells were stained in the highly differentiated Dunning R3327PAP tumor, while most cells were stained in the anaplastic AT1 rat prostatic tumor. Interestingly, castration of rats resulted in an increased Op18 immunoreactivity, within 14 days, in the highly differentiated rat R3327PAP prostatic tumor. In conclusion, the level of Op18 expression seems to be related to cellular differentiation, histological grade, and survival in prostatic cancers. These findings show that Op18 immunoreactivity may be useful as a prognostic marker in prostatic cancer. In addition it may help in the differentiation between highly differentiated prostatic tumors and non-malignant conditions.

Routine prostate biopsies following radiotherapy for prostate cancer: results for 226 patients

OBJECTIVES

To determine the time course of histologic resolution of prostate cancer following radiotherapy (RT) and to correlate biopsy results with clinical outcome.

METHODS

Since July 1990, all patients treated with radical external beam RT for prostate cancer at the General Division of the Ottawa Regional Cancer Centre have had systematic transrectal ultrasound (TRUS) and TRUS-guided biopsies beginning 12 months after RT and then every 6 months until negative or until clinical failure. Thus, 226 patients have had 375 TRUS with four to seven specimens per examination. Stage distribution was T1b: 32, T1c: 11, T2a: 45, T2b: 82, T3: 50, and T4: 6. Median follow-up was 33 months.

RESULTS

Biopsy results were negative in 69.5% of patients by 30 months of follow-up. Thirty-two (14%) had local failure (T1b: 12.5%, T1c: 0%, T2a: 11%, T2b: 15%, T3: 18%, T4: 33%). Seven (3%) had chemical failure, and 47 (21%) had biopsy-only failure. Median follow-up for the biopsy-only failure group is only 19.5 months and mean prostate-specific antigen (PSA) is 1.0 ng/mL. Thirty-nine patients, initially with biopsy-only failure, have converted to negative biopsies at a median of 26 months. Nadir PSA for patients with local failure was 3.9 ng/mL at 14 months versus 0.7 ng/mL at 23 months for those without failure. Patients with late conversion to negative biopsy results had a later nadir PSA of 1.3 ng/mL at 27.3 months.

CONCLUSIONS

Routine prostate biopsy specimens after RT in an unselected population show tumor clearance that is in agreement with long-term clinical follow-up, although tumor may take more than 30 months to resolve. Nadir PSA can be used to predict outcome.

Evaluation of three different AgNOR counting methods in advanced carcinoma of the prostate

We applied the silver staining of nucleolar organizer regions (AgNOR) technique to the pretreatment biopsies of 50 cases of advanced prostate cancer. Three different counting methods were utilized in the enumeration of AgNORs. All methods yielded statistically significant differences of mean AgNOR counts of groups defined by high and low WHO, and by Gleason grades. However, there was overlap among groups, and further analysis of counts by grouping of patients according to their stage, response to treatment, and prognosis was not conclusive. Replicate counts were performed in 10 cases. While intraobserver reproducibility was high by all methods, only the second counting method yielded nonsignificant interobserver variability. There was a significant intratumoral heterogeneity of AgNOR scores. Lack of technical standardization, low reproducibility, and lack of correlation with prognosis limit the use of AgNOR counts in advanced carcinoma of the prostate.

Differential expression of uPA in an aggressive (DU 145) and a nonaggressive (1013L) human prostate cancer xenograft

Prostate cancer has a slow growing noninvasive phase, but, in general, is invasive on diagnosis. An initial step in the invasion of surrounding normal tissue is the activity of proteolytic enzymes such as components of the plasminogen activator system (PA). In cell culture, the primary human prostate cancer cell line 1013L expressed no urokinase type-PA (uPA), while DU 145, a cell line derived from a metastatic lesion, expressed high levels of uPA. The DU 145 cells grew easily as xenografts but the establishment of 1013L in the SCID mice was possible only with the aid of a gelatin sponge (Spongostan). The latency period was 42-64 days, followed by a slow growth phase before a fast growth phase occurred. This fast growth phase was characterized by rapid degeneration of tumor tissue, while high proliferation occurred around the blood vessels. On serial transplantation of tumor material, the growth pattern was similar. Furthermore, the 1013L tumor was encapsulated by connective tissue and no invasiveness could be detected. We found that 1013L tumor homogenates had hardly detectable levels of uPA, i.e., 300-fold lower than we found in the invasive prostate xenograft DU 145. In addition, no expression of uPA was found in the plasma of 1013L tumor-bearing mice whilst uPA antigen was detected in the plasma of DU 145 tumor-bearing mice. In conclusion, the 1013L cell line, which exhibits a nonaggressive pattern, could be a good model for studying progression of prostate cancer to a more aggressive phenotype in vivo and in vitro.

Serum TPS, PSA, and PAP values in relapsing stage D2 adenocarcinoma of the prostate

Serum tissue polypeptide-specific antigen (TPS), prostate-specific antigen (PSA), and prostatic acid phosphatase (PAP) concentrations were serially measured in 31 prostate cancer patients with bone metastases who had relapsed following hormonal therapy. Of these subjects 7 had well-differentiated cancer (G1), 13 patients were assessed to have moderately differentiated tumor (G2) while in 11 subjects poorly differentiated tumor (C13) was found. With increasing tumor grade (G1 to G3), a proportional increase in mean TPS value was found while the increase in respective PAP serotest values was not linear. Simultaneously measured mean PSA values showed a curved effect. Both PSA and PAP serotest concentrations depend on the respective hormone-dependent gene expressions that gradually decrease with tumor dedifferentiation. Therefore, in progressive hormonally treated stage D2 prostate cancer patients an androgen-independent TPS serotest seems to be a useful clinical addition for monitoring protocols. The combined use of TPS, PSA, and PAP seems to give a better reflection of tumor status. According to the bone scan data metastatic tumor mass in G3 carcinomas was virtually equal to cancer burden in G2 tumors. Hence, the marked elevation of TPS serotest values in G3 adenocarcinomas could not be attributed to greater tumor mass but was most likely due to an increase in proliferation rate. Some authors have recently proposed cytokeratins 8, 18, and 19 to be the origin of TPS serum findings. However, cytokeratin content has been proven to be lower in G3 tumors than in better-differentiated neoplasms.(ABSTRACT TRUNCATED AT 250 WORDS)

Endometrioid adenocarcinoma of the prostate: a clinicopathologic and immunohistochemical study

On retrospective review of the tumor registry files between 1979 and 1992 at the North Iowa Medical Center, six cases of endometrioid adenocarcinoma of the prostate were identified among 1582 cases of prostatic carcinoma. Along with long-term clinicopathologic follow-up, immunohistochemical studies of the prostatic tumor tissues were performed. All six cases of endometrioid carcinoma, together with control cases of benign prostatic hypertrophy (BPH) and ordinary adenocarcinoma of the prostate had unequivocal diffuse positive staining for PSA and similar reactivity to ER-D5 and PS2. Thus, endometrioid carcinoma is most likely derived from the prostate or prostatic urethral duct rather than the utricle. However, due to its unusual initial clinical manifestations, biological behavior, and distinctive histomorphology, the term "endometrioid adenocarcinoma of the prostate" is worth preserving.

Heterogeneity of prostate cancer in radical prostatectomy specimens

OBJECTIVE

To understand the morphologic and spatial relationships of the various grades of prostate cancer, we investigated whether poorly differentiated cancer usually arises within the center of a large, well-differentiated tumor or more often forms the periphery or leading edge of the tumor.

METHODS

In a series of one hundred and one completely sectioned whole-mount radical prostatectomy specimens removed from patients with clinical Stage T2 prostate cancer, we mapped the distribution of each of the five Gleason grades and assessed their frequency, proportion, and spatial distribution.

RESULTS

The average number of different grades present in our patients was 2.7 (range 1-5). Over 50 percent of the prostates contained at least three different grades of cancer. The number of different Gleason grades present increased significantly with increasing tumor volume (p < 0.0001). Only 10 percent of the index cancers (largest tumor present) were composed of a single grade and these cancers were small (0.02-1.7 cm3). Among cancers with multiple grades, the most common finding (53%) was a high-grade cancer present within the core of a larger, more well-differentiated tumor; however, the opposite pattern, low-grade cancer present within a larger poorly differentiated cancer, was also common (30%) and predominated in very large cancers (> 10 cm3).

CONCLUSION

Small prostate cancers are often composed of a single grade, usually Gleason grade 2 or 3. But most palpable cancers contain multiple grades which are arranged in heterogeneous and unpredictable geographic interrelationships.

A more objective staging of advanced prostate cancer--routine recognition of malignant endocrine structures: the assessment of serum TPS, PSA, and NSE values

Bone scans, serum tissue-specific polypeptide antigen (TPS), prostate specific antigen (PSA), and neuron-specific enolase (NSE) were assessed in a total of 80 hormonally treated prostate cancer patients. Thirty-nine patients were free of osseous lesions; in 8 subjects, 3 or fewer scintigraphic hot spots were found; in 29 patients, more than 3 bone lesions were recorded. In 3 patients, a partial contribution of endocrine cell cancer structures was found, while in one patient, a homogeneous small cell carcinoma was detected at autopsy. Measurement of the serum PSA test showed a clear-cut rise from stage D0 subjects to stage D2 patients, with a small number of bone lesions (> or = 3). However, a relative decrease in the mean PSA level was measured with further progression in a number of hot spots in bone (> 3). Androgen threshold that is critical for the induction of the PSA (and PAP) expression seems to differ markedly in various cell subpopulations that arise during adenocarcinoma dedifferentiation. This fact explains not only the rise in serum PSA in the majority of progressive and previously castrated subjects after an initial period of hormonal responsiveness, but also a relative decline of androgen-dependent PSA expression with further tumor progression. Localized disease was accompanied with normal or just slightly elevated TPS concentration. In metastatic tumors, serum TPS values revealed a steady increase with the progression in bone. These data seem to reflect not only an increase in tumor proliferation rate with progressively transformed genome, but also the rise in the number of proliferating cells. The presence of nonepithelial transformed tumor structures, such as small cell cancer within a bulk of adenocarcinoma, reduces or normalizes numerical serotests values of both TPS and PSA even during tumor progression. The extent of such decline depends upon the bulk of the endocrine component. The assessment of the above parameters, especially when associated with elevated plasma NSE concentrations, may help in distinguishing an advanced adenocarcinoma with and without elements of malignant neuroendocrine structures. The proposed approach, modified by applying corresponding organ-specific markers, may be checked for its possible general use in staging protocols of various heterogeneous tumors.

Clinical relevance of trans-rectal ultrasound, biopsy, and serum prostate-specific antigen following external beam radiotherapy for carcinoma of the prostate

PURPOSE

To correlate the results of routine transrectal ultrasound-guided prostate biopsies with the usual clinical parameters of digital rectal examination, prostate specific antigen and ultrasound in the follow-up of one hundred patients treated with radical radiotherapy for prostate cancer.

METHODS AND MATERIALS

Stage distribution of the 100 patients was T1b; 19, T2a: 24, T2b: 36, T3: 20, T4: 1. Median follow-up is 26 months (range 15-48). One hundred forty-one ultrasound-guided biopsies have been performed with four to seven specimens at each examination. Initial biopsy was scheduled 12 months after radiotherapy and repeated every 6 months until negative or until there was clinical or biochemical evidence of recurrence.

RESULTS

Negative biopsies were obtained at 12 months (range 9-15) in only 52%. Of 31 patients with a positive first biopsy who have had a second or third examination, 21 converted to negative at 16-29 months (median: 19) (stage T1b: 3, T2a: 6, T2b: 8, T3: 4). All 21 patients had maintained a normal or decreasing prostate specific antigen (PSA). At last review, negative biopsies had been obtained in 74% patients: 79% (15/19) of T1b, 71% (17/24) of T2a, 72%, (26/36) of T2b, and 76% (16/21) of T3/4. No patient with a negative biopsy has had a local recurrence. Transrectal ultrasound alone (sens: 49%, spec: 57%) was no better than rectal exam (sens: 73%, spec: 66%) in predicting a positive post radiotherapy biopsy. Metastatic disease developed in seven patients, 12% (3/26) of those with a positive biopsy and 5% (4/74) of those with a negative biopsy (p < 0.01). All seven presented first with a rising PSA.

CONCLUSION

For patients with a positive biopsy 12 to 24 months after radiotherapy, PSA is the best indicator of biologically active tumor. This preliminary analysis indicates that there may be no need to treat patients with a positive biopsy and negative PSA in the absence of clinical recurrence.

p53 expression in incidental prostatic cancer

Incidental prostate cancer is an indolent disease typically characterized by a benign clinical course. This is not clearly established, however, as recent reports suggest that up to 27% of cases progress with long-term follow-up. The indolent history of this disease led initially to the hypothesis that mutations of the p53 gene would be an infrequent event in this patient population. Archival specimens from 24 patients with Stage A1 carcinomas were evaluated for abnormal p53 expression. In 23 patients the disease was diagnosed after transurethral resection for bladder outlet obstructive symptoms, and in one patient after a radical prostatectomy. Using a monoclonal antibody (PAb 240) and an immunohistochemical technique, a total of 36 microfoci of tumor were evaluated. Thirteen (36%) microfoci were positive with an intense nuclear staining pattern (2+), and eight (22%) microfoci had an intermediate staining pattern. Four areas of prostatic intraepithelial neoplasia also stained positively with a 2+ staining pattern. These results suggest that abnormal p53 expression is a feature of a significant number of incidental prostatic carcinomas and that this occurrence is an early event in the development of the malignant phenotype.

Prostatic carcinoma: problems in the interpretation of prostatic biopsies

We have endeavored to identify problems the pathologist may face in dealing with prostatic carcinoma (PCa). We have covered criteria for diagnosis and have discussed lesions that simulate PCa and the distinguishing features, treatment effects, and specific types of PCa. In many of these areas there is a need for developing objective, reproducible, and measurable criteria. The need for research is obvious.