Evaluation of the automation of immunoenzymatic prcedures in a routine histo/cytopathological laboratory

Eighteen months experience in the use of an automated staining machine for lengthy histological and immunohistochemical stains in a routine pathology laboratory is described. The apparatus yields an important saving in time for technicians and can maintain the quality of staining at a standardized high level. A disadvantage is the larger volumes of reagents required. Introduction of the machine is recommended when at least five different but lengthy stains have to be performed each day. The considerable gain in time for the technicians has important consequences for the management of pathological laboratories in the near future.     

Demonstration of calcitonin and carcinoembryonic antigen (CEA) in medullary carcinoma of the thyroid (MCT) by immunoperoxidase technique

The presence of calcitonin and of carcinoembryonic antigen (CEA) was studied in six cases of medullary carcinoma of the thyroid using an immunoperoxidase technique. In five cases the material was obtained surgically and in one at autopsy. Tissue from primary tumours as well as from metastases was studied. Calcitonin and CEA were identified within all the tumours studied, although their pattern of distribution and staining intensity varied both within the cells and within the tumour. Some parts of the tumour contained both CEA and calcitonin, while others stained positively only for one of these substances. In some parts of the tumour there was no positive staining for either substance. Within the cells, CEA showed a typical linear distribution along cell surfaces, while calcitonin showed a more even cytoplasmic distribution and the deposits were more granular. Normal tissue surrounding tumour deposits did not show positive staining. It is considered that cells of medullary carcinoma of the thyroid contain both calcitonin and CEA. Identification of CEA and calcitonin in tumour tissue can be used as a diagnostic aid to identify medullary carcinoma of the thyroid. Iit is considered that these substances are being produced by this tumour and can be used as tumour markers.     

CLONING OF THE MOUSE FIBRONECTIN V-REGION AND VARIATION OF ITS SPLICING PATTERN IN EXPERIMENTAL IMMUNE COMPLEX GLOMERULONEPHRITIS

Increased mRNA and protein expression of extracellular matrix (ECM) components, including fibronectin, occurs during the development of glomerulonephritis and glomerulosclerosis in immunologically mediated kidney diseases. However, in addition to these quantitative changes in ECM expression, qualitative changes in these molecules may contribute to malformations in the composition of the glomerular matrix. These qualitative changes may include alterations in the splicing pattern of the V-region of fibronectin, since this region plays a role in its accumulation. The splicing patterns of this region have been studied in chronic graft-versus-host disease (GvHD) in mice, a model of lupus nephritis, and in chronic serum sickness (CSS) in rats, a model of immune complex nephritis. Cloning of the mouse fibronectin V-region from kidney tissue revealed 96·1 per cent homology with the corresponding domain in rat fibronectin. PCR (polymerase chain reaction) analysis of RNA from isolated glomeruli revealed three isoforms of this region in both mouse and rat fibronectin, namely inclusion or exclusion of the whole region, or exclusion of only the CS1 domain. In both models, increased exclusion of the V-region was observed early in the disease. However, in GvHD the splicing pattern returned to normal, whereas in CSS the shift persisted during the course of the experiment. Differentiated expression of fibronectin isoforms may exert an important effect on the structure and biological function of the glomerulus and may thus play a role in the development of glomerulonephritis and glomerulosclerosis.     

Quantitative, microscopical, computer-aided diagnosis of endometrial hyperplasia or carcinoma in individual patients

There are many significant differences, but also considerable overlap between the quantitative histopathological features of mild and marked atypical endometrial hyperplasias and well and moderately differentiated carcinomas, thus preventing its application to individual patient care. To try to overcome this problem, a classification rule for the diagnosis in individual patients, using discriminant analysis has been developed. Utilizing nine quantitative features, all the above four groups can be adequately separated. None of the carcinomas was misclassified as hyperplasia, and only one case of marked atypical hyperplasia was erroneously classified as well differentiated carcinoma, but with a probability of carcinoma 0.75, hyperplasia 0.25. By contrast, the classification probabilities of all the confirmed carcinomas exceeded 0.90. Therefore, using 0.90 as a classification level ('threshold'), a reliable rule is obtained. A slightly more simple classification rule distinguishes between all the hyperplasias and all the carcinomas. In this way, all the cases of the test set were correctly classified. The classification rules can be used to select patients with benign disease for hormone therapy(Kistner 1973) as an alternative to hysterectomy, and can be programmed in an inexpensive microcomputer. The quantitative techniques are relatively easy, and are capable of being performed in most histopathological laboratories.