Diagnosis of vasculogenic impotence: combination of penile xenon-133 washout and papaverine tests

Current practice of diagnosis and reporting of prostatic intraepithelial neoplasia and glandular atypia among genitourinary pathologists

The criteria for diagnosing prostatic intraepithelial neoplasia (PIN) and lesions suspicious for cancer are described in the literature. However, it is unknown how these are applied in practice by experts in genitourinary (GU) pathology. A questionnaire was sent to 93 GU pathologists in countries around the world with the purpose of surveying current practices. The response rate was 69% including 40 North American pathologists and 24 from other continents. For preneoplastic lesions, the term PIN was universally endorsed by the respondents. PIN was graded by 83%, usually as low/high-grade PIN (LGPIN/HGPIN) or as HGPIN only. Most respondents would usually not report lesions that may qualify for LGPIN. A majority (81%) did not specify architectural patterns of PIN. With both HGPIN and invasive cancer present, 69% would still mention HGPIN. Among the diagnostic criteria for HGPIN were any nucleoli visible (52%), or nucleoli seen in at least 10% of cells (33%). However, 56% would diagnose HGPIN in the absence of prominent nucleoli, most commonly based on prominent pleomorphism, marked hyperchromasia or mitotic figures. The number of cores involved with HGPIN was specified by 50%. Lesions suspicious for but not diagnostic of carcinoma were reported by 45% as atypia, atypical glands or suspicious for cancer and by 42% as atypical small acinar proliferation. The degree of suspicion was further defined by 41%. Our survey data may serve as a guideline to general pathologists on how to diagnose and report atypia and PIN in prostate biopsies.

Platelet-derived growth factor A and B chains and the alpha and beta receptors in prostatic intraepithelial neoplasia

BACKGROUND

The objective of this study was to evaluate the expression of platelet-derived growth factor (PDGF A, PDGF B) and their receptors (PDGF alpha, PDGF beta) in prostatic intraepithelial neoplasia (PIN) and adenocarcinoma.

METHODS

Peroxidase-antiperoxidase immunoperoxidase labeling was used to detect the extent of antibody labeling in 29 different high grade PIN specimens.

RESULTS

PDGF A and PDGF alpha were uniformly expressed in glandular epithelial and stromal cells, whereas PDGF B was not expressed by either tissue. However, PDGF beta was lightly expressed in a uniform manner by both the glandular epithelial and stromal cells.

CONCLUSIONS

The data suggest that an autocrine loop may exist in which the epithelial cells of high-grade PIN express PDGF AA and PDGF alpha to modulate growth of precancerous lesions.

Experimental research on the morphofunctional differentiation of the rat ventral prostate: roles of the gonads at birth

In the male rat, a dramatic increase in serum testosterone (T) of testicular origin occurs during the first few hours of postnatal life. This experiment sought to determine whether this increase affects the physiology of the adult rat ventral prostate. Male rats were castrated at the time of caesarean delivery performed at different precise stages between 21 days and 22 days of gestation (0h males). Newborn male rats were castrated after spontaneous delivery at 22 days of gestation at 6, 12, 24 or 48 h after birth. Some male rats were castrated at fetal stage 21 days 13-15 h and injected at the time of surgery with 1, 2.5 or 5 micrograms of testosterone propionate (TP). Control males were sham operated at fetal stage 21 days 13-15 h and castrated at 23 days postnatal. At 30 days of age, each male was given T replacement therapy through a T filled silastic capsule until the time of sacrifice at 100 days of age. Before T implantation at 30 days of age, castration at 0 h or 48 h after birth does not impair neither branching morphogenesis nor the organization of the prostatic acinus. In contrast, the histological structure of the ventral prostate of the 0 h males implanted with T from puberty on is greatly disturbed. Cribriform and severe atypic hyperplastic acini with various epithelial cell arrangements are common. The alveolar sheath of the prostatic glands and the interacinar stroma are enlarged. In acini with severe intraepithelial hyperplasia, the disorganized epithelium rests over a thick basement membrane that stains strongly for laminin. In some 0 h males, epithelial cells break through the periacinar fibromuscular sheath and invade the interacinar stroma. It is as though all the categories of cells comprising the ventral prostate were not programmed in the absence of neonatal androgens. The secretory activity and the expression of Prostate Binding Protein (PBP) are impaired in the ventral prostate of the 0 h males. Castration performed after 12 h after birth has no deleterious effect on either secretory activity or PBP expression. The critical period during which perinatal T affects the histological structure and the functional differentiation of the ventral prostate extends from fetal stage 21 days up to 1 or 2 days postnatal. A single injection of 2.5 micrograms TP, a dose which mimicks the postpartum T surge is sufficient for programming the histological structure and the functional differentiation of the adult ventral prostate.

Pre-neoplastic lesions of the prostate

Acinar carcinoma of the prostate is the third most frequently registered cancer and its incidence is expected to increase as life expectancy increases. Consequently, there have been attempts to introduce possible screening programmes for early detection of prostatic carcinoma. In this context the histopathologist has a role in that potential pre-neoplastic lesions have to be recognized. Two such pre-neoplastic lesions in the prostate are adenomatous hyperplasia and prostatic intraepithelial neoplasia. In this article the histological features of these lesions, their differential diagnosis and their pre-malignant potential are reviewed.

Pathology review in an early prostate cancer detection program: results from the American Cancer Society-National Prostate Cancer Detection Project

Biopsy materials obtained in the American Cancer Society National Prostate Cancer Detection Project were reviewed at the Central Pathology Laboratory at the Armed Forces Institute of Pathology. Of 265 cases submitted, 177 were diagnosed as prostatic carcinoma, 7 as prostatic intraepithelial neoplasia (PIN), 13 as atypical glands or atypical hyperplasia, and the remaining 68 were benign hyperplasias. Irrespective of the means of detectin or the grading system used (Gleason or WHO-Mostofi), a large majority of the cancers were detected as low-grade tumors. Of 27 cases of PIN reported, 20 were associated with cancer, leaving 7 cases with the sole diagnosis of PIN. These data may indicate the increased use of prostate-specific antigen (PSA), digital rectal examination (DRE), and transrectal ultrasound (TRUS) in the United States is shifting the spectrum of prostate cancer pathology toward early low-grade tumors.

Developmental estrogenization and prostatic neoplasia

The association of estrogens with benign prostatic hyperplasia and prostatic cancer has been widely studied, but no conclusive evidence exists for a role of estrogens in prostatic disease. This paper reviews the literature and describes studies which have sought to show a correlation of estrogens and alterations in the prostates of humans and experimental animal models. Using the developmentally estrogenized mouse model, we propose an alternative role for estrogens as a predisposing factor for prostatic diseases: estrogen exposure during development may initiate cellular changes in the prostate which would require estrogens and/or androgens later in life for promotion to hyperplasia or neoplasia. Thus, the critical time for estrogen action would be during the development of the prostatic tissue. We further suggest that estrogen-sensitive cells may remain in the prostate and be more responsive to estrogens later in life or less responsive to the normal controlling mechanisms of prostatic growth.

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).

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.

The role of nuclear medicine in the evaluation of the male genital tract

Scintigraphic techniques for evaluation of impotence are still evolving. Blood pool studies are most useful in assessing the integrity of arterial inflow, but may also be used to generate indices of venous leak. A non-imaging version of this test may represent a simple and cost-effective alternative. Washout of intracavernosal xenon during erection seems the most useful method of testing venous integrity. Washout using Tc-RBC may emerge as a convenient alternative to the more technically difficult xenon examinations. Development of more effective pharmacologic stimuli may further improve the utility of this quantitative and physiologic examination.

Radionuclide genital imaging

Despite the emergence of newer cross-sectional imaging approaches, radionuclide techniques have maintained a significant role in genital imaging. While ultrasound is clearly superior for evaluation of scrotal anatomy, radionuclide scrotal imaging remains the most effective method for differentiating between testicular torsion and epididymitis. Labeled red blood cells have been used for varicocele detection in infertile men. Since radionuclide techniques can demonstrate the physiologic status of organs, they play a useful role in evaluating men with impotence (penile scan) and infertile women whose tubal patency is in question (radionuclide hysterosalpingogram).

Pathology of carcinoma of the prostate

In this presentation the authors review the pathology of prostatic carcinoma (PCa), and discuss criteria for pathologic diagnosis, premalignant lesions, lesions that simulate PCa, immunopathology, special types of PCa, effects of therapy on the prostate, and recent efforts to improve diagnostic and prognostic capabilities. The possible role of study of nucleolar organizing regions is reported. A new method for demonstration of chromosome in formalin-fixed, paraffin-embedded tissue is presented. The need for research in all aspects of pathology is emphasized.

A dynamic dual isotope radionuclear method of quantifying penile blood flow

A new radionuclear method of quantifying arterial and venous blood flow of the penis is described. The technique is based on the simultaneous recording of the change in blood volume and venous outflow in the flaccid and erect states, which is produced pharmacologically. The change in penile blood volume is determined by measuring the change in the technetium-labeled red blood cell activity with time. Venous outflow is recorded with a xenon washout technique. The isotope data are used to compute arterial and venous flows with a complex computerized mathematical formula. Three basic blood flow patterns have been noted that distinguish normal patients from those with arterial insufficiency and venous leakage. The study is relatively easy and noninvasive to perform, and it appears to quantify penile blood flow accurately.

Nuclear medicine in problems of fertility and impotence

Nuclear medicine techniques may be used to test fallopian tube patency and penile vascular inflow and outflow. Radionuclide hysterosalpingography (HSP) is a readily performed method of evaluating fallopian tube patency, and is believed to be more physiologic and functionally informative than the accepted radiologic method of contrast HSP. The test is simple to perform and interpret and offers an accurate alternative to the contrast examination. For scintigraphic evaluation of impotence, blood pool studies are most useful in assessing the integrity of arterial inflow, but may also be used to generate indices of venous leak. Washout of xenon after subcutaneous injection, in the flaccid state, has been used as a measure of baseline penile perfusion, as has intracavernosal injections in the flaccid penis. Intracavernosal xenon washout during erection seems the most useful method of testing venous integrity. Washout using technetium-99m (99mTc)-labeled red blood cells (99mTc-RBC) may emerge as a convenient alternative to the more technically difficult xenon examinations.

Dual radioisotopic study: a technique for the evaluation of vasculogenic impotence

Arterial and venous systems are the main points for the evaluation of vasculogenic impotence. To evaluate both of these systems in the same study we propose a dual radioisotopic study in which 99mtechnetium (99mTc) and 133xenon (133Xe) were used. The changes in 99mTc and 133Xe radioactivities administered intravenously and intracavernously, respectively, were monitored before and after intracavernous papaverine injection. These changes were determined as time activity curves, which were generated from the region of interest over the penis. A 99mTc penogram index derived from the 99mTc time activity curve was significantly different in the control and arteriogenic impotence groups (131.67 +/- 74.6 versus 62.94 +/- 51.6, p less than 0.01). A meaningful correlation between 99mTc penogram index results and duplex ultrasonographic findings were observed (r = 0.905). 133Xe penogram index, derived from the 133Xe washout curve was significantly different in the control and venogenic impotence groups (-25.65 +/- 24.9 versus -56.09 +/- 13.4, p less than 0.01). Also, a meaningful correlation was obtained between pharmacocavernosometry and 133Xe penogram index results of venogenic impotent patients (r = 0.86). These findings suggest that the dual radioisotopic study will be a useful technique in the evaluation of the entire vascular system of the penis, since it is a noninvasive method.

Prostatic intraepithelial neoplasia (PIN): morphological clinical significance

Premalignant lesions of the prostate fall into two categories. The first category includes formation of new, usually small, glands which are either abnormally distributed or show minimal nuclear atypia or both. Morphologically, this lesion presents the differential diagnostic alternatives of micro-acinar hyperplasia on the one hand and a low grade micro-acinar cancer on the other. If the presence or absence of nuclear anaplasia or acinar dispersion (i.e., stromal invasion) raises any degree of doubt, atypical glands are diagnosed. This is the category that is considered by some to be the precursor of well differentiated prostate cancer. The second category is prostatic intraepithelial neoplasia (PIN). We have defined PIN as an intra-acinar or ductal proliferation of secretory cells with unequivocal nuclear anaplasia, which corresponds to nuclear grade 2 and 3 invasive prostate cancer. We consider PIN as essentially carcinoma in situ. The lesion designated by some as PIN 1 is classified by us as atypical hyperplasia.

Radionuclide studies in impotence

Impotence may be of physiological origin with causes including vascular or neurological pathology. Alternatively, it may be of psychogenic origin. Clinicians can distinguish between psychological and organic impotence by observing nocturnal penile tumescence. Non-radionuclide investigations for organic impotence include penile plethysmography or pulse Doppler analysis for arterial supply, cavernosometry for venous drainage, and biothesiometry or evoked potentials for neurological pathology. Radionuclide studies are primarily based on the use of technetium 99m-pertechnetate, 99mTc-red blood cells, or xenon 133 to study the blood flow, with or without pharmacological intervention, commonly papaverine.