Morphometric analysis of gastric dysplasia

Dysplasia discrimination in intestinal-type neoplasia of the esophagus and colon via digital image analysis

Determining gastrointestinal tract dysplasia level is clinically important but can be difficult, and given this challenge, we investigated colonic and esophageal dysplastic progression using digital image analysis (IA). Whole slide images were obtained for colonic normal mucosa (NCM), hyperplastic polyps (HP), conventional tubular adenomas (TA), and adenomas with high-grade dysplasia (HGD), and esophageal intestinal metaplasia negative for dysplasia (IM), indefinite for dysplasia (IFD), low-grade dysplasia (LGD), and HGD. Characteristic nuclei were circumscribed, and parameters discriminating groups included nuclear circumference (μm), area (μm(2)), and 15 positive pixel count (PPC) algorithm IA measurements. In colon polyps and esophageal lesions, average nuclear area and circumference ranged 30-108.6 μm(2) and 27.5-48.9 μm, respectively. Differences for average nuclear area and circumference met statistical significance (p < 0.05) between diagnostic groups in the esophagus and colon, except for IM versus IFD nuclear area. Pixel intensity (brightness) separated lesions within both groups with statistical significance except for colonic TAs versus HPs and esophageal LGD versus IM. HGD nuclei in both groups demonstrated more pixel staining heterogeneity than other lesions. Hierarchical clustering and principal component analysis demonstrated that lesions with similar diagnoses tended to cluster together on a low- to high-grade spectrum. Our results confirm that quantitative IA is an effective adjunct reflecting dysplasia in colon polyps and Barrett esophagus lesions. Nuclear area, circumference, and PPC algorithm findings distinguished lesions in a statistically significant manner. This suggests utility for future studies on similar methods, which may provide an adjunctive ancillary technique for pathologists and enhance patient care.

Predictive variables for the biological behaviour of basal cell carcinoma of the face: relevance of morphometry of the nuclei

We did a morphometric analysis of 130 histological sections of basal cell carcinoma (BCC) of the face to find out whether morphometric variables in the structure of the nuclei of BCC cells could serve as predictors of the biological behaviour. We considered the following variables: maximum and minimum diameters, perimeter, nuclear area and five form factors that characterise and quantify the shape of a structure (axis ratio, shape factor, nuclear contour index, nuclear roundness and circumference ratio). We did a statistical analysis of primary and recurring tumours and four histology-based groups (multifocal superficial BCCs, nodular BCCs, sclerosing BCCs and miscellaneous forms) using a two-sided t test for independent samples. Multifocal superficial BCCs showed significantly smaller values for the directly measured variables (maximum and minimum diameters, perimeter and nuclear area). Morphometry could not distinguish between primary and recurring tumours.

Chief cell proliferation of the gastric mucosa mimicking early gastric cancer: an unusual variant of fundic gland polyp

We describe a hitherto unknown lesion of gastric chief cell proliferation mimicking structurally mucosal gastric cancer. The unremarkable cytology of the cells, their very low Ki-67 index, the inclusion of occasional parietal cells and especially ultrastructural evidence of chief cell differentiation proved helpful in the differentiation from early gastric cancer. The exact classification of the alteration remains unresolved. The presence of microcysts suggests that the lesion is a variant of fundic gland polyp formation.

Routine morphometrical analysis can improve reproducibility of dysplasia grade in Barrett's oesophagus surveillance biopsies

BACKGROUND

The grade of dysplasia found in Barrett's oesophagus surveillance biopsies is a major factor to determine follow up and treatment. However, it has been reported that the reproducibility of the grading system is not optimal.

AIMS

To compare routine and expert dysplasia grades in Barrett's oesophagus surveillance biopsies. To evaluate prospectively morphometrical grading support and to assess the pitfalls in its daily application.

METHODS

Consecutive biopsies (n = 143) were graded routinely by experienced general surgical pathologists as no dysplasia (ND), indefinite for dysplasia, low grade dysplasia (LGD), and high grade dysplasia (HGD). Two expert gastrointestinal pathologists blindly reviewed all sections. The stratification index of nuclei, mean nuclear area, and Ki67area% were assessed routinely according to a strict protocol. With these features, the previously described morphometrical grade was calculated for each case. The grades provided by the experts, surgical pathologists, and morphometry were compared.

RESULTS

The general pathologists graded many more cases as dysplastic than did the experts. Complete agreement between the experts' grades and the original grades was 50 of 143 (35%). Sixty four of the 71 original LGDs and 11 of the 23 original HGDs were downgraded by the experts, whereas one LGD was upgraded. In 93 of the 143 biopsies, at review pitfalls or special characteristics of a technical nature (tangential cutting, severe inflammation, ulcer or the squamocylindrical junction very close by, among others) were seen in the part of the biopsy marked as diagnostic. These probably contributed in part to the original overdiagnoses and could have been prevented or corrected. The morphometrical grading model has not been developed to compensate for this; application of the current morphometrical grading method is not allowed and may result in erroneous (usually too high) morphometrical grades. In spite of this, all HGDs according to the experts were recognised as such by morphometry, also in these technically less adequate sections or areas. However, 46% of the experts' downgrades occurred in technically adequate sections and thus were caused by a difference in interpretation. Here, morphometrical support proved to be useful because, in agreement with the experts, it downgraded 51% of the original LGDs, upgraded one of eight NDs to LGD and one of 39 LGDs to HGD.

CONCLUSIONS

Experts downgraded a high proportion of biopsies graded as LGDs and HGDs by the surgical pathologists. Morphometrical grading can be used for daily quality control; the results were close to those of the experts and corrected a large number of cases erroneously graded by surgical pathologists.

An automated machine vision system for the histological grading of cervical intraepithelial neoplasia (CIN)

The histological grading of cervical intraepithelial neoplasia (CIN) remains subjective, resulting in inter- and intra-observer variation and poor reproducibility in the grading of cervical lesions. This study has attempted to develop an objective grading system using automated machine vision. The architectural features of cervical squamous epithelium are quantitatively analysed using a combination of computerized digital image processing and Delaunay triangulation analysis; 230 images digitally captured from cases previously classified by a gynaecological pathologist included normal cervical squamous epithelium (n=30), koilocytosis (n=46), CIN 1 (n=52), CIN 2 (n=56), and CIN 3 (n=46). Intra- and inter-observer variation had kappa values of 0.502 and 0.415, respectively. A machine vision system was developed in KS400 macro programming language to segment and mark the centres of all nuclei within the epithelium. By object-oriented analysis of image components, the positional information of nuclei was used to construct a Delaunay triangulation mesh. Each mesh was analysed to compute triangle dimensions including the mean triangle area, the mean triangle edge length, and the number of triangles per unit area, giving an individual quantitative profile of measurements for each case. Discriminant analysis of the geometric data revealed the significant discriminatory variables from which a classification score was derived. The scoring system distinguished between normal and CIN 3 in 98.7% of cases and between koilocytosis and CIN 1 in 76.5% of cases, but only 62.3% of the CIN cases were classified into the correct group, with the CIN 2 group showing the highest rate of misclassification. Graphical plots of triangulation data demonstrated the continuum of morphological change from normal squamous epithelium to the highest grade of CIN, with overlapping of the groups originally defined by the pathologists. This study shows that automated location of nuclei in cervical biopsies using computerized image analysis is possible. Analysis of positional information enables quantitative evaluation of architectural features in CIN using Delaunay triangulation meshes, which is effective in the objective classification of CIN. This demonstrates the future potential of automated machine vision systems in diagnostic histopathology.

Computerized quantitative pathology for the grading of dysplasia in surveillance biopsies of Barrett's oesophagus

Decision models for surveillance of Barrett's oesophagus (BO) are governed by the grade of dysplasia on endoscopic biopsy, but subjective grading is prone to observer variation. Computerized morphometry and immunoquantitation can objectively discriminate between different grades of dysplasia in oesophagectomy specimens with BO. The present study evaluated the feasibility of such quantitative analysis on surveillance biopsies of BO. Biopsy criteria for quantitative analysis were defined, excluding 101 (21%) of 472 archival BO surveillance biopsies. In the remaining haematoxylin and eosin (H&E) sections, 105 areas that distinctively displayed no dysplasia (ND), low-grade dysplasia (LGD) or high-grade dysplasia (HGD) were demarcated. Agreement on double-blind examination by two experienced pathologists was reached in 66 areas (63%; kappa: 0.44). For 21 ND/LGD and 11 LGD/HGD disagreement areas, corresponding sections for p53 and Ki67 immunohistochemistry were available. The best combination of two discriminating features was stratification index (SI) with p53 area % for ND versus LGD (89% correct classification), and SI with Ki67 area % for LGD versus HGD (91% correct classification). Fifteen of the 21 ND/LGD disagreement areas could be classified uniquely as either ND or LGD by SI and p53, and eight of the 11 LGD/HGD disagreement areas as either LGD or HGD by SI and Ki67. Correlation coefficients for repeated measurements of SI, Ki67, and p53 by the same observer were 0.94, 0.92, and 0.86, and by two independent observers 0.86, 0.93, and 0.92, respectively. Computerized quantitative pathology on BO surveillance biopsies is feasible provided that well-defined biopsy criteria are used. Using a combination of features associated with cellular differentiation and proliferation, such as SI, p53, and Ki67, quantitative pathological analysis assists in reducing diagnostic variability in the grading of dysplasia during surveillance of BO.

Computerized quantitative pathology for the grading of dysplasia in surveillance biopsies of Barrett's oesophagus

Decision models for surveillance of Barrett's oesophagus (BO) are governed by the grade of dysplasia on endoscopic biopsy, but subjective grading is prone to observer variation. Computerized morphometry and immunoquantitation can objectively discriminate between different grades of dysplasia in oesophagectomy specimens with BO. The present study evaluated the feasibility of such quantitative analysis on surveillance biopsies of BO. Biopsy criteria for quantitative analysis were defined, excluding 101 (21%) of 472 archival BO surveillance biopsies. In the remaining haematoxylin and eosin (H&E) sections, 105 areas that distinctively displayed no dysplasia (ND), low-grade dysplasia (LGD) or high-grade dysplasia (HGD) were demarcated. Agreement on double-blind examination by two experienced pathologists was reached in 66 areas (63%; kappa: 0.44). For 21 ND/LGD and 11 LGD/HGD disagreement areas, corresponding sections for p53 and Ki67 immunohistochemistry were available. The best combination of two discriminating features was stratification index (SI) with p53 area % for ND versus LGD (89% correct classification), and SI with Ki67 area % for LGD versus HGD (91% correct classification). Fifteen of the 21 ND/LGD disagreement areas could be classified uniquely as either ND or LGD by SI and p53, and eight of the 11 LGD/HGD disagreement areas as either LGD or HGD by SI and Ki67. Correlation coefficients for repeated measurements of SI, Ki67, and p53 by the same observer were 0.94, 0.92, and 0.86, and by two independent observers 0.86, 0.93, and 0.92, respectively. Computerized quantitative pathology on BO surveillance biopsies is feasible provided that well-defined biopsy criteria are used. Using a combination of features associated with cellular differentiation and proliferation, such as SI, p53, and Ki67, quantitative pathological analysis assists in reducing diagnostic variability in the grading of dysplasia during surveillance of BO.

Gastric intestinal metaplasia type III cases are classified as low-grade dysplasia on the basis of morphometry

The aim of this study was to try to place gastric intestinal metaplasia, type III (type III IM) in the stepwise chain of events from atrophic gastritis to cancer. A number of dysplastic, periulcer regenerative, and type III IM lesions were qualitatively diagnosed (and graded) blindly and independently by several pathologists. These lesions were further analysed by means of quantitative parameters, with the aim of differentiating dysplastic from regenerative changes. Inconsistencies between the qualitative and quantitative classification (about 7 per cent of cases) were eliminated and homogeneous groups (low-grade dysplasia, high-grade dysplasia, regenerative changes) were obtained. These cases were taken as the gold standard against which type III IM was compared. The results indicate that the great majority (91.4 per cent) of cases of type III IM fulfil the nuclear and architectural criteria for low-grade dysplasia.

Morphometry of gastric carcinoma: its association with patient survival, tumour stage, and DNA ploidy

Morphometric image analysis of nuclear features was performed on tissue from 46 patients who had had curative resections for gastric cancer. Clinical, pathological, flow cytometric, and follow-up data were available for these patients, which were drawn from a larger, previously reported series. The morphometric data were compared with patient survival, clinico-pathological status, and DNA ploidy. Univariate survival analysis revealed that morphometric parameters were not significantly related to survival, but examination of clinico-pathological data showed lymph node involvement, involvement of the resection margin, and lymphatic invasion to be significantly associated (P < 0.01) with patient prognosis. Multivariate survival analysis using the Cox model found only lymph node and resection margin involvement to be independently related to survival. Comparison of morphometric results with the clinico-pathological parameters showed various features, relating to nuclear size, and its variation to be significantly associated (P < 0.01) with the presence of lymphatic invasion, resection margin involvement, and tumour pattern (intestinal/diffuse). A comparison of morphometry with flow cytometric analysis in these cases showed that nuclear size was not significantly related to either DNA aneuploidy or the DNA proliferative index.

Morphometrical analysis of nuclear abnormality of tubular tumors of the stomach with image processing

Nuclear size and shape on histological specimens were used to quantify nuclear abnormality in gastric tubular tumors. A valid technique for this morphometrical analysis by image processing was developed. Furthermore, the present study examined the nuclear size and shape to determine if they were reliable criteria to be used for differential diagnosis. Nuclear area, maximum diameter and maximum width on the histological specimens were defined as factors to represent nuclear size. Nuclear aspect ratio represented nuclear shape. Histological features revealed varied degrees of condensation of nuclei; this was due to different protocols for preparing the histological specimens. This finding indicated that the size of intermediate lymphocytes on the same specimens should be measured as a control in order to estimate the degree of nuclear condensation. The present study also demonstrated that at least 200 nuclei should be measured on the histological specimens to obtain accurate nuclear size and shape. Histologically, the nuclei in benign tubular adenoma and borderline lesions tended to be spindle-shaped, while those in well-differentiated type tubular adenocarcinoma tended to be round and swollen. The nuclei in borderline lesions were larger than those in benign tubular adenoma and smaller than those in well-differentiated type tubular adenocarcinoma. Our results for the above 4 factors corresponded well with these histological findings. The nuclear size and shape on histological specimens were concluded to be reliable criteria for assessing nuclear abnormality in gastric tubular tumors and useful ones for differential diagnosis.

Morphometrical analysis of structural abnormality of tubular tumors of the stomach with image processing

Four indices, index of tubular density, index of dispersion of tubular size, degree of complexity of tubular shape and frequency of complex-shaped tubuli, were defined to quantify the structural abnormalities of gastric tumors in morphometrical analysis by image processing. The values of each index corresponded well with the degree of each structural abnormality found pathologically. These indices were considered to be valid for representing their respective structural factors. There were significant differences among the mean values of the scores calculated by a formula using all 4 indices of benign tubular adenoma, borderline lesion and well-differentiated type tubular adenocarcinoma (P less than 0.05). Therefore, the discriminant formula was considered to be valid for integrating these indices and for representing structural abnormality of gastric tubular tumors.

Planimetry in pathology--a method in its own right besides stereology and automatic image analysis

Under the term planimetry all possibilities of quantitative morphological description of structures at the two-dimensional level which do not require densitometry and do not consider the 3rd spatial dimension are subsumed. Because planimetry has several advantages with respect to preparation techniques and structure recognition compared to stereology and expensive densitometric image analysis systems, it seems necessary to give a synoptic description of planimetry as a morphometric method in its own right in pathology. This should lead to a clinically orientated development in parallel to stereology and densitometry. The recent status and advances with regard to the methods of measuring and evaluation are discussed.

Morphometric definition and grading of gastric intestinal metaplasia

Type I and type III intestinal metaplasia in gastric mucosa have been examined using morphometric methods. Tissue (volume per cent gland, lumen, epithelium, goblet cell vacuoles) and nuclear parameters (area, with related standard deviation, and form factors) were used as indicators of gland crowding, nuclear-cytoplasmic ratio, nuclear atypia, and pleomorphism. In type III intestinal metaplasia, there is significantly (i) greater nuclear pleomorphism, (ii) a higher nuclear-cytoplasmic ratio, and (iii) smaller and less numerous goblet cell vacuoles in both the upper and the lower parts of the crypts. These two parameters have significantly higher values in the lower than in the upper part of individual crypts. No cell population with large pleomorphic nuclei characterized type III metaplasia, though there was more variation in nuclear size.

A combination of cytological and architectural morphometry in assessing regenerative hyperplasia and dysplasia in ulcerative colitis

Morphometry and stereology were used to assess the cytological and architectural characteristics of regenerative and dysplastic colorectal mucosal abnormalities in ulcerative colitis. Reproducibility of measurements was assessed and found to be good, confirming the objective and reproducible nature of morphometric analysis. Discriminant analysis between the morphometric features of regenerative mucosal change and low-grade dysplasia revealed the significant cytological and architectural variables from which a cytological and architectural score were derived. The architectural score was capable of classifying all of the cases into their correct diagnostic category, although a combination of the two scores provided better separation of cases. Probability density analysis was carried out so that probabilities of group membership could be allocated to cases, given their cytological and architectural scores. Discriminant analysis was also applied to low- and high-grade dysplasia. Important cytological and architectural variables were identified and used separately to derive scoring systems. In combination, the dual scoring of lesions was capable of separating low- from high-grade dysplasia, although overlap was still evident. Again, probability density analysis allowed the allocation of cases into one or other category, although a closer examination showed that such a rule could not successfully classify a new set of low- and high-grade dysplasia cases. Quantitative histological analysis of mucosal abnormalities is shown to be of use in the objective diagnosis of reactive and dysplastic change in patients with ulcerative colitis. The use of simple scoring systems and probability based allocation of cases promotes the future role of morphometric techniques in the diagnostic laboratory.

Gastric dysplasia: inter-observer variation, sulphomucin staining and nucleolar organizer region counting

Gastric dysplasia is regarded as a pre-neoplastic lesion and is generally believed to have higher potential for malignant transformation with increasing grade. To obtain consistency in diagnosis and management, reproducible diagnostic criteria are needed. We have used the classification system of the International Study Group on Gastric Cancer--ISGGC and investigated the interobserver variation in histological diagnosis. A Kappa statistic of 0.579, which reflects moderate agreement, was obtained for variation between two experienced pathologists. The prevalence of type III intestinal metaplasia was studied and found to occur in 55% of dysplastic areas, but in only 9% of hyperplastic areas (P less than 0.01). In addition, the correlation of mean nucleolar organizer region (AgNOR) counts with diagnostic categorization was investigated. A significant inter-observer variation was found between an experienced pathologist and a postgraduate student and only one of the observers obtained statistically significant separation of mean AgNOR counts between the categories of high-grade dysplasia, low-grade dysplasia, atypical hyperplasia, simple hyperplasia and normal.

Gastric dysplasia

The morphological diagnosis of gastric dysplasia is based on the presence of changes in the architecture, cytology and differentiation of the epithelium and mucosal glands. Two morphological types exist: gastric (foveolar) and metaplastic. Definite morphological criteria for gastric dysplasias can be presented. The present morphological grading of dysplasia into mild, moderate or severe is, however, arbitrary and subjective. The available investigations show that dysplasia and overt carcinoma have several biological and epidemiological links that indicate that a dysplasia-cancer sequence operates in the pathogenesis of at least a proportion of gastric carcinomas. The data available in the literature strongly indicate that severe dysplasia is highly predictive for coexisting or shortly appearing carcinoma. The literature on the clinical significance of dysplasia of mild or moderate grade, however, is as yet scanty and inconsistent.

The role of morphometry in predicting prognosis in pancreatic islet cell tumors

Morphometry of 31 pancreatic islet cell tumors was examined to determine the value of this technique in assessing tumor behavior. Patients were followed for a mean period of 5.1 years (range, 1 month-14 years) after diagnosis. Initially 17 localized and nine metastatic tumors were studied. Discriminant analysis was carried out on these cases and identified nuclear/cytoplasmic ratio and number of nuclei/mm2 as the significant discriminatory features. These were combined to derive a classification rule which was capable of correctly identifying localized and metastatic tumors in 92% of cases. The classification rule was applied subsequently to an additional five test cases, all of which were classified successfully. The failure of increased nuclear size and pleomorphism to correlate with malignancy in these tumors was confirmed. Tumors which metastasized had significantly greater gross diameters than localized lesions, but overlap existed. Mitotic counts were not a helpful discriminatory feature. Morphometry may be useful in improving histologic assessment of pancreatic islet cell tumor behavior.

A morphometric assessment of transitional mucosa in the colon

Quantitative morphometric analysis was used in 10 resection specimens to assess so-called transitional mucosa immediately adjacent to colorectal carcinoma. Eleven nuclear and cellular variables were measured from the malignant epithelial area and from zones of increasing distance (1 cm) from the lesion. In addition, mean mucosal height was assessed for each zone. Morphometrical differences between the mucosa immediately adjacent to the malignant epithelium and that taken at some distance from it were determined by Mann-Whitney U tests. Transitional mucosa showed increased mucosal height but no nuclear differences from normal mucosa. Other work has shown that there are nuclear morphometric differences associated with premalignant conditions in the colon. Thus, the suggestion that transitional mucosa represents early neoplastic change cannot be supported.

Architectural morphometry in ulcerative colitis with dysplasia

Semi-automatic image analysis was used to assess the architectural features of normal colorectal mucosa and ulcerative colitis with and without dysplasia. Eight measured and derived morphometric variables were compared with the histological grading. The main data-set variation was due to: (1) the area of mucosa and epithelium per unit length of muscularis mucosae; (2) mean mucosal and epithelial height; and (3) the percentage epithelium and number of crypts per unit length of muscularis mucosae. Discriminant analysis using the variables mean epithelial height and mean lamina propria area per unit length of muscularis mucosae separated normals (n = 10) from high-grade dysplasia (8). The classification rule allocated low-grade dysplasia (8) to the high-grade category and 60% of regeneration cases (10) to the normal mucosa group. Scatter plots of the two discriminating variables separated normal and regenerative mucosa from dysplasia. Histological review of overlapping cases allowed redesignation of a high-grade dysplasia lesion as low grade. Architectural morphometry may be of use in assessing premalignant mucosal changes in ulcerative colitis as a guide to patient surveillance and therapy.

The significance of nuclear diameter in the biologic behavior of thyroid carcinomas: a retrospective study of 127 cases

The relationship between nuclear diameter and biologic behavior was studied in 127 cases of thyroid carcinoma. Using a sonic digitizer coupled to a minicomputer, nuclear diameters of 200 randomly selected cancer cells from each case (hematoxylineosin-stained paraffin sections) projected at X 400 magnification were traced and averaged. A total of 25,400 measurements were made. The nuclear diameters varied from 4.7 to 13.1 micron. By analysis of variance, the nuclear diameters were significantly different (p = 0.0007) among the four types of thyroid cancers, being largest in the undifferentiated cancers (8.7 +/- 0.8 micron) and smallest in the medullary cancers (6.6 +/- 0.1 micron). Nuclear diameter was also significantly correlated with degree of tumor differentiation (p = 0.002), maximal tumor diameter (p = 0.03), mitotic rate (p = 0.002), and 5-year survival (p less than 0.05) for all types of tumors. The correlation between nuclear diameter and disease stage was significant only for undifferentiated cancers (p = 0.04). No significant correlations were seen between nuclear diameter and duration of disease, sex, or age of the patient.

A morphometric study of invasion and metastasis in human colorectal carcinoma

The cell nuclei within primary and nodal secondaries of colorectal carcinomas were analysed morphometrically in order to identify a primary subpopulation with similar characteristics to cells involved in lymphatic metastasis. No significant difference in nuclear area was seen between cell populations of the primary and secondary. However, a regional variation in mean nuclear area was present, suggesting a relationship between cells at the invasion front and in early nodal metastasis. This subpopulation differed from the cell populations of the primary and more advanced secondaries. These results are consistent with the existence of a morphometrically identifiable metastatic subpopulation within the invasion front of colorectal carcinoma.

Classification of normal colorectal mucosa and adenocarcinoma by morphometry

Semi-automatic image analysis was used to make a morphometrical assessment of 15 nuclear and cellular variables in normal (n = 20) and malignant (n = 30) colorectal epithelium. Principal components analysis on the matrix of correlations between variables identified four main sources of variation within the dataset. These were, in decreasing order of importance: (1) nuclear size, nuclear cytoplasmic ratio and nuclear position within the cell; (2) the variability of nuclear size; (3) nuclear elongation and polarity; (4) nuclear shape and its variation. Discriminant analysis was conducted between histologically normal mucosa (n = 10) and adenocarcinoma in ulcerative colitis (n = 20). Using stepwise variable selection, the mean nuclear cytoplasmic ratio (normal, mean 20.4 (s.d. +/- 2.0); tumour, mean 39.7 (s.d. +/- 7.0)) and the coefficient of variation of nucleus to cell apex distance (normal, mean 19.2 (s.d. +/- 7.5); tumour, mean 47.8 (s.d. +/- 9.1)) were chosen as discriminating features. They were used to derive a discriminant function which gave perfect discrimination between the two groups. Scatter plots of these two variables confirmed complete separation of normal mucosa from adenocarcinoma and provided a simple method of applying the discriminant function. Discriminatory performance did not deteriorate when the function was applied to further normals (n = 10) and adenocarcinoma (n = 10). This study highlights the descriptive differences between normal and malignant colorectal epithelium and shows that case allocation may be made to these two lesion categories using a morphometrically-derived classification rule.

Morphometrical analysis in ulcerative colitis with dysplasia and carcinoma

Semi-automatic image analysis was used to assess the epithelium in ulcerative colitis with dysplasia and carcinoma. There were three main sources of variation within the dataset: (1) nuclear size, nuclear cytoplasmic ratio and nuclear stratification; (2) the variation of nuclear size; and (3) nuclear shape and polarity. Discriminant analysis chose the mean nuclear cytoplasmic ratio % and the coefficient of variation of nucleus to cell apex distance to derive a scoring system which completely separated normal mucosa (n = 20) and carcinoma (n = 30). The classification rule allocated all high grade dysplasia to the tumour category. Scores for regeneration and low grade dysplasia overlapped with each other and the normal and tumour groups. Scatter plots of the two discriminating variables showed good separation of regeneration and high grade dysplasia, and a degree of overlap with low grade dysplasia. The scatter plots allowed identification of overlapping and misallocated cases, requiring review of their histology and redesignation of the diagnosis in five cases. This study confirms quantitatively the visual criteria used in grading mucosal changes and their trend from regeneration through dysplasia to carcinoma. It underlines the necessity of assessing not only cytological but also architectural and inflammatory components when diagnosing regeneration and low grade dysplasia. Mucosal morphometry may be of use in confirming high grade dysplasia which is an indication for colectomy.

Gastric dysplasia: a stereological and morphometrical assessment

The grading systems of gastric dysplasia suffer from the lack of criteria that separate the changes with an acceptable reproducibility. Repeatable and objective grading of the lesion can be obtained by morphometrically measuring histological criteria normally employed in qualitative grading. In 54 consecutive antrum biopsy specimens in which a blind, independent agreement on the grade of dysplasia had been reached between four independent pathologists, stereological and nuclear morphometrical features have been studied. Single variate, bivariate and multivariate analyses have been performed. Architectural parameters, such as volume and surface densities of glands and epithelium, are especially good discriminators both between mild and moderate, and between moderate and severe dysplasia. Features describing arrangement and shape of nuclei, and nucleolar size are of additional help in improving the objective distinction between moderate and severe dysplasia.

Measuring S100 protein and neurone specific enolase in melanocytic tumours using video image analysis

Using a computed video image analysis system, the staining intensity for both neurone specific enolase (NSE) and S100 protein was measured in sections from 19 malignant melanomas and 16 benign melanocytic lesions. The results of this study confirm previous reports that NSE and S100 protein are useful markers for malignant melanoma. NSE staining intensity in the cases of malignant melanoma was significantly higher than that in benign naevi (p = 0.011). Intensity of staining for S100 protein was not significantly higher in the malignant melanomas. There was, however, a significant S100 gradient when comparing superficial and deep intradermal portions of these tumours (p = 0.003). This feature was not seen in benign naevi. The greatest intensity of S100 protein staining was found in the deeper portions of the malignant melanomas. This gradient difference was not seen with staining for NSE. Although it seems that the overall intensity of staining for NSE is more effective in differentiating between benign and malignant lesions, the difference in staining intensity between the superficial and deep portions of the tumour may be the better indicator of adverse behaviour in lesions in which the diagnosis of malignancy is uncertain.

DNA flow cytometry of histological material from dysplastic lesions of human gastric mucosa

DNA flow cytometry has been carried out on histologically processed human gastric tissue showing varying grades of gastric dysplasia, intramucosal carcinoma and regenerative changes. No cases of DNA aneuploidy were encountered in cases showing regenerative changes or mild or moderate dysplasia. DNA aneuploidy was found in 5/7 cases of severe dysplasia and 3/11 cases of intramucosal cancer. Irregularities of the G0/G1 peak were encountered in a further 18 samples including normal and regenerative gastric mucosa. However these were not thought to indicate DNA aneuploidy. The interpretation of these abnormalities and the affect on the frequency with which DNA aneuploidy is reported in pathological lesions is discussed.