Nuclear volume estimates in prostatic atypical adenomatous hyperplasia

OBJECTIVE: To investigate nuclear volume estimates by the point-sampled intercepts method in atypical adenomatous hyperplasia (AAH) as compared with nodular hyperplasia and well-differentiated prostatic adenocarcinoma. STUDY DESIGN: The study group consisted of 27 formalin-fixed, paraffin-embedded, whole-mounted radical prostatectomy specimens that contained foci of nodular hyperplasia, atypical adenomatous hyperplasia and well-differentiated adenocarcinoma (Gleason pattern 1 and 2). Representative sections were selected for stereologic estimation of volume-weighted mean nuclear volume by the point-sampled intercepts method. On each focus, an average of five fields of vision were systematically chosen. RESULTS: The quantitative results indicate an increase in nuclear volume from nodular hyperplasia (209 +/- 65 micron 3) to AAH (237 +/- 85 micron 3) and prostate adenocarcinoma (436 +/- 106 micron 3). Significant differences were found (F = 39.0, P < .001) with two group comparisons (Scheffe's procedure) between prostate cancer and AAH (P < .001) or nodular hyperplasia (P < .001). The difference between AAH and benign hyperplasia was not signifcant. CONCLUSION: The results indicate that three-dimensional estimates of the nuclear size discriminate AAH and nodular hyperplasia from well-differentiated prostate adenocarcinoma. These findings suggest that AAH is probably a histologic variant of benign prostatic hyperplasia the exact relationship of which to prostatic adenocarcinoma remains to be determined.     

High-grade prostatic intraepithelial neoplasia

High-grade prostatic intraepithelial neoplasia is considered the most likely precursor of prostatic carcinoma. The only method of detection is biopsy; prostatic intraepithelial neoplasia (PIN) does not significantly elevate serum prostate-specific antigen concentration and cannot be detected by ultra-sonography. The incidence of PIN in prostate biopsies averages 9% (range, 4%-16%), representing 115,000 new cases of PIN diagnosed each year in United States. PIN has a high predictive value as a marker for adenocarcinoma, and its identification warrants repeated biopsy for concurrent or subsequent invasive carcinoma. Carcinoma will develop in most patients with PIN within 10 years. PIN is associated with progressive abnormalities of phenotype and genotype that are intermediate between normal prostatic epithelium and cancer, indicating impairment of cell differentiation and regulatory control with advancing stages of prostatic carcinogenesis. Androgen deprivation therapy decreases the prevalence and extent of PIN, suggesting that this form of treatment may play a role in chemoprevention.     

Prognostic significance of mean nuclear volume in pancreatic adenocarcinoma

OBJECTIVE: To evaluate the correlation of stereologically estimated mean nuclear volume of tumor cells with other clinicopathologic prognostic features and survival in pancreatic ductal adenocarcinoma. STUDY DESIGN: The study included 27 patients with primary pancreatic ductal adenocarcinoma. A stereologic method proposed by Gundersen et al was used for the estimation of mean nuclear volume in hematoxylin and eosin-stained histologic sections of each case. Mean nuclear volume values were compared statistically with histopathologic prognostic feature groups and survival. RESULTS: The mean nuclear volume values of tumor cells ranged from 296.83 to 982.79 microns 3 (mean, 633.906 +/- 212.310). Higher values of mean nuclear volume were significantly related to advanced tumor stage and the presence of distant metastasis (Kruskal-Wallis, P = .036; Mann-Whitney U, P = .020). In contrast, nodal stage, tumor grade, perineural invasion, lymphatic and blood vessel invasion, and size of tumor showed no statistical relation to mean nuclear volume of tumor cells. Mean nuclear volume was found to be a significant predictor of survival in univariate analysis (P = .016). CONCLUSION: Estimation of mean nuclear volume may help in predicting the extent of disease and clinical behavior in pancreatic adenocarcinoma.     

Stereologic estimation of mean nuclear volume in well-differentiated adenocarcinoma and carcinoma in situ of the gallbladder

OBJECTIVE: To investigate mean nuclear volume of cells in well-differentiated adenocarcinomas (20 cases) and carcinoma in situ (20 cases) of the gallbladder by the principle of estimation of the volume of particles with arbitrary shapes. STUDY DESIGN: Hematoxylin and eosin-stained, 4-micron-thick, vertical sections from formalin-fixed, paraffin-embedded tissue blocks were analyzed by using a projection microscope with a 100:1 oil immersion objective (NA 1.3); the final magnification was 2,500:1. The measurements were carried out in 10 microscopic fields for each slide. Mean nuclear volume was obtained by the stereologic method of point-sampled intercepts for vertical sections. RESULTS: Mean nuclear volume in well-differentiated adenocarcinomas (127.67 +/- 46.95 micron 3) was significantly larger than in carcinoma in situ (69.17 +/- 15.74 micron 3) (P < .000001). CONCLUSION: Stereologic estimation of mean nuclear volume may be helpful in the discrimination of malignant and borderline lesions of the gallbladder.     

Chromatin texture in high grade prostatic intraepithelial neoplasia and early invasive carcinoma

OBJECTIVE: To evaluate individual nuclei from high grade prostatic intraepithelial neoplasia (PIN) lesions with early invasive carcinoma foci in the area of microinvasion and in the gland in which the microinvasion originated. STUDY DESIGN: High-resolution, digitized images of nuclei from defined locations were recorded and segmented, and karyometric variables were computed. These included a set of 93 features, which form a nuclear signature characterizing the spatial and statistical distribution of the nuclear chromatin. Nuclei in the glandular epithelium were recorded sequentially, along the basal cell layer, at increasing distances from the point of microinvasion and by random selection in the region of microinvasion. RESULTS: At a distance > 60 nuclear locations from the point of microinvasion, the nuclear signatures corresponded to those seen in high grade PIN. Between 40 and 20 nuclear locations removed from the microinvasion focus the signatures began to change gradually until at a distance of 15-5 locations they strongly resembled the signatures seen in adenocarcinoma. The total optical density decreased to values seen in adenocarcinoma, and the nuclear chromatin had finer granularity. While nuclei in high grade PIN followed a widely dispersed total optical density distribution suggestive of wide-ranging aneuploidy, the nuclei in the region of microinvasion exhibited a less dispersed and bimodal total optical density distribution. CONCLUSION: The chromatin texture signatures showed a clear trend: there was an obvious attenuation as the measured nuclei approached the microinvasion area. The decrease in total optical density at the microinvasion might suggest the emergence of one or two clones that can be responsible for the invasive phenotype.     

Stereological estimates of nuclear volume correlated with histopathological grading and prognosis of bladder tumour

The aim of this retrospective study is to provide morphometric data which make grading of urinary bladder tumours objective and reproducible by stereological estimation of nuclear volume using the principle of estimating of the volume of particles of arbitrary shape. The study includes 92 specimens: 12 from normal bladder mucosa, and 80 from bladder tumours (15 grade I, 45 grade II, 19 grade III and one grade IV according to Bergkvist et al. 1965). After standard fixation, embedding, sectioning and hematoxylin-eosin staining, an unbiased estimate of the mean volume of nuclei sampled with a change proportional to the volume: (Formula: see text) was calculated. Here l0 is the length of the intercept through a test point hitting a nucleus measured in a random direction through the test point. The weighted means of nuclear volume in bladder tumours are spread over a wide range and show a strong correlation with the Bergkvist grade. Moreover, the relationship between the weighted mean volume of nuclei in bladder tumours and the prognosis is very good. Only one of 35 patients with a mean nuclear volume below 300 micron 3 died of bladder cancer whereas 18 of 19 patients with a mean nuclear volume above 500 micron 3 developed invasives tumours or died of their disease. This simple and fast estimate of nuclear volume seems to provide objective data of high prognostic value.     

Histometric features for the grading of prostatic carcinoma

Histometric features for the objective grading of prostatic adenocarcinoma in histologic specimens were analyzed in five cases each of well, moderately and poorly differentiated lesions. Tissue sections from the selected cases were stained by the Feulgen method and digitized by a video-based microphotometer. Twenty total fields were recorded for each grade: ten at high resolution (an image sampling of 0.5 micron per pixel) and ten at low resolution (0.8 micron per pixel), with two fields per case recorded at each resolution. The images were segmented by an automated expert system-guided scene segmentation procedure. The performance of that procedure was measured by comparing the automated counts of nuclei in the segmented fields to the visual counts made by a pathologist in the same fields. For well, moderately and poorly differentiated cases, respectively, the nuclear counts made by the expert system at high resolution were 2.7%, 4.2% and 4.7% higher than the visual counts (as estimated from a total of 6,628 nuclei), but 1.2%, 2.5% and 1.1% lower at low resolution (10,329 nuclei). High-resolution features and tissue textural features were computed for each case. The high-resolution features showed good separation between the three groups of cases. The tissue textural features showed consistent separation between well and moderately differentiated cases. The relaxation of the spatial resolution (to 0.8 micron/pixel spacing) did not affect the selection of features, but led to less separation between the data from different grades. In conclusion, the automated system performed satisfactorily in distinguishing sections of prostatic tumors of varying degrees of differentiation.     

Epigenetic heterogeneity of high-grade prostatic intraepithelial neoplasia: clues for clonal progression in prostate carcinogenesis

High-grade prostatic intraepithelial neoplasia (PIN) is the most likely precursor of prostate adenocarcinoma, but the frequency and timing of epigenetic changes found in prostate carcinogenesis has not been extensively documented. Thus, the promoters of three genes (APC, GSTP1, and RARbeta2) involved in prostate carcinogenesis were tested by quantitative methylation-specific PCR in tissue DNA from 30 prostate carcinomas, 128 high-grade PIN lesions, and 30 normal prostate tissue samples dissected from 30 radical prostatectomy specimens using laser capture microdissection. The percentage of methylated alleles (PMA) was calculated for each gene, and hierarchical cluster analysis was used to define the degree of similarity of epigenetic alterations among the various samples. We found that PMA values of APC and RARbeta2 were higher than those of GSTP1 in all three types of tissue samples and median PMA values for all three genes were higher in prostate cancer. By cluster analysis, 26 of 30 prostate carcinomas and 82 of 128 high-grade PIN lesions were grouped in the "high methylation" branch, whereas 24 of 30 normal prostate tissue samples were allocated in the "low methylation" branch. Although high-grade PIN lesions are epigenetically more similar to prostate carcinoma than to normal prostate tissue, paired prostate carcinoma and high-grade PIN lesions did not always segregate together. We concluded that APC and RARbeta2 hypermethylation is frequent in normal prostate tissue and the progressive enrichment in cells carrying methylated alleles observed in high-grade PIN and prostate carcinoma is consistent with clonal progression. Because GSTP1 promoter methylation is mainly observed in prostate carcinoma and some high-grade PIN lesions, it represents an important marker for the transition of in situ to invasive neoplasia.     

Quantitative analysis of prostatic intraepithelial neoplasia on tissue sections.

The changes in nuclear morphology (karyometry) and DNA content in prostatic intraepithelial neoplasia (PIN) were analyzed on tissue sections. The cases of PIN were subdivided into PIN 1 and PIN 2 based on the degree of proliferation and the anaplasia of the secretory cells lining the ducts and acini. Cases of nodular hyperplasia (NH) and adenocarcinoma were also studied for comparative purposes. Karyometric analysis showed a progression of most values from NH to PIN to carcinoma. The DNA analysis showed a decrease in the frequency of nuclei in the diploid range and an increase in the percentage of nuclei in the other ploidy regions (especially between 2c and 4c and in the tetraploid range) from NH to PIN to carcinoma. Forward stepwise discriminant analysis showed similarities between NH and PIN 1 and between PIN 2 and carcinoma. These findings suggest that the evolution towards adenocarcinoma is characterized by progressive morphologic derangements of the nuclei and by the transformation of the diploid DNA content into a nondiploid one, with the changes taking place at the level of PIN 2.     

Effects of total parenteral nutrition on rat bile canaliculi: a stereologic analysis

OBJECTIVE: To quantitate, in a stereologic manner, changes in bile canalicular morphology before and after choleretic infusion of total parenteral nutrition (TPN) and to determine whether TPN produces changes in localized regions within the hepatic lobule. STUDY DESIGN: Livers were obtained from sham-operated on normal adult male rats (control) and from rats that received intravenous TPN solution containing 20% glucose and 3.5% Molipron F. The tissues, obtained by a rigorous sampling procedure, were systematically subjected to stereologic analysis. Measurements were made on electron micrographs at two levels of magnification by point, intersection and profile counts, and then volume, surface area and length were estimated per unit parenchymal volume. RESULTS: The surface area of the canalicular wall per parenchymal volume increased significantly (from 5.33 x 10(-2) to 6.73 x 10(-2) microns 2/micron 3) after TPN treatment, as did the length of microvilli (from 0.241 to 0.267 microns/micron 3). However, the volume of bile canalicular lumina per parenchymal volume (0.306% and 0.320%), total length of bile canaliculi (1.05 x 10(-2) and 1.06 x 10(-2) microns/micron 3) and diameter of microvilli (8.73 x 10(-2) and 8.94 x 10(-2) microns) remained constant. CONCLUSION: These results indicate that changes in canalicular shape and microvillus hypertrophy may cause lowering efficiency of the bile flow rate.     

Changes in Biomarker Expression in the Development of Prostatic Adenocarcinoma

In spite of the prevalence of prostatic adenocarcinoma, the development and natural history of this malignancy is poorly understood. This paper reviews the current knowledge of biomarker expression during the development and progression of prostatic adenocarcinoma. Emphasis is placed on the comparison of biomarker expression in benign prostatic epithelium, intraepithelial neoplasia (PIN), a putative preinvasive lesion, and prostatic adenocarcinoma. Within the benign epithelium, the proliferative potential is restricted to the basal cells as demonstrated by the expression of proliferating cellular nuclear antigen (PCNA). The strong expression of the bcl-2 protein, an inhibitor of apoptosis, supports the concept that the basal cells or a subpopulation of the basal cells represent the stem cell of the epithelium. In addition, the strong expression of growth factor receptors such as the epidermal growth factor receptor (EGFr), p185^erbB-2, p180^erbB-3, and c-met suggests that the growth of the basal cells is regulated by autocrine or paracrine factors. The luminal cells express secretory products such as prostate specific antigen and prostatic acid phosphatase, but demonstrate little expression of PCNA as well as growth factor receptors and proto-oncogene products. These observations are consistent with the theory that the luminal cell population is derived from the differentiation of the basal cells. In contrast to the normal epithelium, PCNA expression is frequently detected in the dysplastic luminal cells of the PIN lesion. Likewise, strong expression of p185^erbB-2, p180^erbB-3 and the c-met proto-oncogene product is also detected in the luminal cells of PIN lesions. Other factors which are strongly expressed by the dysplastic luminal cells include the nm23-Hl gene product, tumor associated glycoprotein-72 (TAG-72), fatty acid synthetase (FASE) and proteolytic enzymes. These findings suggest that PIN lesions are derived from an impairment of the differentiation of basal cells. The majority of biomarkers such as PCNA, p185^erbB-2, p180^erbB-3, TAG-72, nm23-Hl and FASE which are strongly expressed in PIN lesions are also expressed in prostatic adenocarcinoma supporting the concept that PIN is a preinvasive lesion. Mutations of the p53 tumor suppressor gene, as well as strong expression of transforming growth factor a and bcl-2 typically occur in advanced stage prostatic adenocarcinomas and therefore likely represent late events in the development of prostatic adenocarcinoma.     

Cyclin A and Ki-67 with DNA content in benign and malignant prostatic epithelial lesions.

OBJECTIVE: To evaluate the usefulness of immunohistochemical staining of cyclin A and Ki-67 together with DNA content in the classification of benign prostatic hyperplasia, prostatic intraepithelial neoplasm (PIN) and prostatic carcinoma foci and to compare these parameters with each other and with parameters obtained from conventional histopathology. STUDY DESIGN: We selected 37 carcinoma, 18 PIN and 8 hyperplastic foci from prostatectomies done during 1996 and 1997 at Turku University Central Hospital. Cyclin A and Ki-67 staining was assessed by immunohistochemistry and DNA content by image cytometry. RESULTS: The hyperplastic, PIN and carcinoma foci differed clearly in their 2.5c exceeding rates, image cytometric proliferation indices and staining indices for cyclin A and Ki-67. No significant differences were found between these histologic entities in their modal DNA ploidy values. In carcinomas, cyclin A and Ki-67 indices differed between low, intermediate and high Gleason and World Health Organization grading groups. Diploid and tetraploid carcinomas had similar cyclin A and Ki-67 indices, which differed from those of aneuploid carcinomas. CONCLUSION: The 2.5c exceeding rate and image cytometric proliferation index as well as the cyclin A and Ki-67 indices differed significantly between different types of prostatic lesions. Cyclin A and Ki-67 had good correlations with the histologic grade of carcinoma.     

Application of alpha-methylacyl coenzyme A racemase immunohistochemistry in the diagnosis of prostate cancer: a review

Alpha-methylacyl coenzyme A racemase (AMACR) is a recently discovered enzyme protein that has been shown to be increased at both the mRNA and protein levels in prostatic adenocarcinoma as compared with normal prostatic tissues. Since its discovery, AMACR has gained wide acceptance for use in the diagnosis of prostatic adenocarcinoma in conjunction with morphology and immunohistochemical staining for basal cell markers. Numerous studies have consistently shown high sensitivity and specificity of AMACR for prostate cancer. This review focuses on AMACR expression in prostate cancer and its morphologic variants, high grade prostatic intraepithelial neoplasia, adenosis and benign conditions of the prostate. In addition, we discuss AMACR expression in other tumors. We also focus on the utility and technical aspects of the now-popular "triple stain" immunohistochemical antibody cocktail, consisting of antibodies to high-molecular-weight keratin, p63 and AMACR. Finally, we emphasize diagnostic pitfalls in the application of AMACR to small, atypical foci of glands seen on prostate needle core biopsy and project future diagnostic as well as clinical applications for the protein.     

Structure-activity relationships in corpora allata of the cockroach Diploptera punctata: roles of mating and the ovary

Morphometric studies were made on corpora allata of the cockroach Diploptera punctata from animals in which increasing gland size is not coupled to hormone synthesis (ovariectomized mated females; last-instar larvae) and in which gland size is coupled to hormone synthesis (normal mated and virgin females; penultimate-instar larvae). Cell number, gland volume, and juvenile hormone synthesis were measured. From electron micrographs, nuclear, cytoplasmic, and extracellular volumes; and cell membrane area were calculated; and fine structure described. Low-activity glands of ovariectomized mated females resembled high-activity glands from mated females in high cell number, large overall and cytoplasmic volume, and low nuclear-cytoplasmic ratio; they differed in having organelles typical of low-activity glands, mitochondria with dense matrices and large whorls of smooth endoplasmic reticulum. Inactive lastinstar larval glands resembled mated ovariectomized, female glands in increased cell number and organelles characteristic of inactive glands; however, their nuclearcytoplasmic volume ratio was much higher. Penultimate cytoplasmic volume ratio was much higher. Penultimate larval glands with high activity per cell resembled active glands of normal mated females. Ovariectomy did not change morphometric parameters of virgin female glands; thus mating results in increase in size of adult female glands whereas the growing ovary is needed for changes in mitochondria and endoplasmic reticulum associated with high juvenile hormone synthesis.     

Computer-assisted grading of adenocarcinoma in prostatic aspirates

Conventional cytologic grading of fine needle aspirates of prostatic adenocarcinoma has been shown neither to be reproducible nor to correlate well with histologic grading. This study developed a tumor grade classification based on computerized cytomorphometric features and compared the results to conventional grading of companion tissue sections. The image analysis system evaluated architectural features of the aspirates (mainly cell cluster features and interrelationships) as well as nuclear features. Thirty-five prostatic adenocarcinomas (8 well, 19 moderately and 8 poorly differentiated) were evaluated. Discriminant functions based on data collected at medium and high resolution distinguished between aspirates from low-grade (well-differentiated) and high-grade (poorly differentiated) adenocarcinomas with 81% accuracy. Moderately differentiated cancers could not be classified as a distinct group. This study suggests that accurate grading of prostatic adenocarcinoma in fine needle aspirate smears requires the evaluation of medium-resolution features related to specimen cellularity and uniformity or crowding of cell clusters as well as of high-resolution features of nuclear area, perimeter and coarseness of chromatin texture. These findings are compared to those of other schemes for the cytologic grading of prostatic aspirates.     

Morphometry and discriminant analysis of the endometrium.

The authors dated 100 normal endometrial biopsies. Only endometrial specimens with histologically confirmed subphases and no evidence of organic disease were accepted for study. The morphometry and stereologic measures of the glands, lumina and endometrial epithelium were assessed. Quantitative assessment of the normal endometrium supported the histologic events that occur in the endometrial cycle (proliferative and secretory phases). There was a progressive increase in morphometric and stereologic values of the glands, epithelium and lumina during the endometrial cycle. Using stepwise discriminant analysis, 94% of the specimens were correctly classified into the categories of proliferative and secretory phase; two quantitative parameters were required, the epithelial volume density and longest luminal diameter. When three subphases within proliferative and secretory endometrium were considered, the overall accuracy was 90% and 78%, respectively.     

Prostatic intraepithelial neoplasia: an overview

Prostatic intraepithelial neoplasia (PIN) is the most established precursor of prostatic carcinoma. The presence of prominent nucleoli within an existing duct structure is an easy way to identify the disorder. Four main patterns of high-grade PIN (HGPIN) have been described: tufting, micropapillary, cribriform, and flat. In addition to exhibiting similar cytologic features, both HGPIN and prostatic carcinoma are associated with increased incidence and severity with age, and with high rates of occurrence in the peripheral zone of the prostate. HGPIN and prostate cancer share genetic and molecular markers as well, with PIN representing an intermediate stage between benign epithelium and invasive malignant carcinoma. The clinical significance of HGPIN is that it identifies patients at risk for malignancy. With the increased use of extended biopsy protocols, clinicians are more likely to identify HGPIN and less likely to miss concurrent carcinoma. Androgen deprivation therapy decreases the prevalence and extent of PIN, and may play a role in chemoprevention. Preliminary studies suggest that selective estrogen receptor modulators may also prevent the progression of HGPIN to prostate cancer.     

Mean nuclear area of fine needle aspirates of primary preoperative palpable breast carcinoma using image cytometry

OBJECTIVE: Early, operable breast cancers in appropriate patients are increasingly being treated preoperatively using neoadjuvant chemotherapy. A good response rate is seen with high grade tumors. Nuclear size, which may reflect the grade of the tumor, is also of possible prognostic value in breast cancer. STUDY DESIGN: We measured the mean nuclear area (MNA) of 114 consecutive preoperative fine needle aspirates of palpable, operable breast cancers. We used computerized image cytometry to measure nuclear area to determine tumor biology and possible grade prior to treatment. RESULTS: Histologic grade distribution was as follows: low grade, 15%; moderate grade, 40%; and high grade, 45%. Mann-Whitney test for trend on tumor size and histologic grade between MNA showed a significant relationship between MNA and tumor size (P=.016) but no significance between MNA and histologic grade (P =.22). The chi2 and Fisher Exact Test between MNA and node-positive or -negative patients showed no significance. CONCLUSION: When correlating MNA with tumor size and histologic grade, high MNA is present at a higher frequency as tumor size and histologic grade increase.