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T J Stephenson

Publications and source records attributed to T J Stephenson.

At least 109 records · Page 6Linked to original sources
PubMed1988

Feasibility of new prognostic classification for rectal cancer.

Sixty slides from 60 blocks taken from 30 colonic carcinomas were circulated twice to six histopathologists of varying experience. Five of the six pathologists showed a good to excellent intraobserver agreement for assessment of the character of the invasive margin (0.44 less than kappa less than 0.82), which was not significantly affected by sampling (0.40 less than kappa less than 0.56, comparing both slides from each tumour) or observer (five of six pathologists agreeing on 46 of 60 slides). Pathologists were unreliable in assessing peritumoural lymphocytic infiltrates, with only two pathologists achieving moderate levels of intraobserver agreement (-0.03 less than kappa less than 0.52). The interobserver agreement for peritumoural lymphocytic infiltrates was also low (kappa less than 0.29) between the three most experienced pathologists. The assessment of peritumoural lymphocytic infiltrates was significantly affected by sampling, the two pathologists with the lowest intraobserver variation achieving kappa values of 0.21 and 0.10 between the 30 paired slides from each tumour. The character of the invasive margin was reliably assessed, was not dependent on sample, and added useful prognostic information, but peritumoural lymphocytic infiltration is not a reproducible observation and may therefore not add useful prognostic information in routine use.

Feasibility Studies↗
PubMed1987

On the nature of clear cell acanthomas.

Five clear cell acanthomas were studied using a panel of immunohistological markers. The results were compared with those from basal cell papillomas, with and without clear cell change, and with lesions of psoriasis and lichen planus. The results do not support the contention that these lesions are variants of basal cell papillomas nor that they are true neoplasms.

Basal Cell Carcinoma↗
PubMed1987

Visceral brown fat necrosis in postperinatal mortality.

Fat necrosis was present in 22 of 400 cases of consecutive postperinatal mortalities investigated to assess the presence and pattern of deep fat necrosis. In just over 50% of the cases of fat necrosis the cause of death was categorised as sudden infant death syndrome, which also showed more severe degrees of necrosis. The mechanism of necrosis may be vascular hypoperfusion, possibly related to shock, and brown adipose tissue, on account of its high metabolic activity and rich capillary plexus, may be particularly vulnerable to infarction. The occurrence of fat necrosis in association with other causes of death did not provide any definite clue as to the nature of the alleged shock.

Adipose Tissue, Brown↗
PubMed1987

Paget's disease in an epidermal cyst.

A case of Paget's disease involving both the epidermis of the nipple and an adjacent epidermal cyst is reported. Immunohistochemistry showed similarity between the infiltrating cells in both sites and those of the underlying mammary adenocarcinoma. Epidermal cysts may be involved in a variety of disease processes which affect the epidermis in general and, unless they are subjected to careful histopathological examination, these diseases may be overlooked.

Breast Diseases↗
PubMed1986

Adenomatoid tumours: an immunohistochemical and ultrastructural appraisal of their histogenesis.

The histogenesis of adenomatoid tumour has continued to provoke debate since Golden and Ash suggested the term in 1945 for a characteristic benign neoplasm typically found in the uterus, fallopian tube or epididymis. Endothelial, epithelial, mesonephric, müllerian and mesothelial histogenesis have been suggested. The balance of evidence suggests mesothelial derivation, but two recent studies point to endothelial origin for at least some of these tumours. Twenty-two histologically typical adenomatoid tumours were studied by electron microscopy, mucin histochemistry and immunohistochemistry. Ultrastructurally, all cases showed vacuolated cells bearing long bushy microvilli and the features were not those of endothelial cells. Glandular spaces contained acid mucopolysaccharide consistent with hyaluronic acid. Immunohistochemical double labelling techniques showed the cells lining such spaces to contain cytokeratin in the absence of factor VIII related antigen and receptors for Ulex europaeus I lectin which were expressed in the endothelium of tumour blood vessels. The evidence points to mesothelial histogenesis in all cases examined.

Epididymis↗
PubMed1986

Characterization and immunogenicity of HSV-1 antigens obtained following zwitterionic detergent treatment.

A preparation was obtained from herpesvirus hominis type 1 (HSV-1) infected cells using the zwitterionic detergent, Empigen BB. The preparation was partially purified by ultracentrifugation over a cushion of 20% sucrose. Serological characterization by ELISA and immuno double diffusion, using both polyclonal and monoclonal antibodies shows this preparation to contain HSV glycoproteins, including gC, gD and gE. Immunization of Balb/c mice elicited serum antibody responses against both HSV-1 and HSV-2 viruses, complete protection against HSV-1 (strain WAL) and partial protection against HSV-2 (strain 333).

Animals↗
PubMed1986

Comparison of Ulex europaeus I lectin binding and factor VIII-related antigen as markers of vascular endothelium in follicular carcinoma of the thyroid.

Factor VIII-related antigen (F VIII-RAg), a well established marker for endothelial cells, and the lectin Ulex europaeus agglutinin I (UEA-1), a newly described marker, were used in immunoperoxidase techniques to demonstrate endothelial cells in 30 follicular neoplasms of the thyroid and so to assist in detection of vascular invasion. Both endothelial cell markers made visible a greater number of instances of vascular invasion than were detected on routine elastic stains, but UEA-1 lectin gave more reliable staining of endothelium lining large capsular veins and of blood vessels within the tumour than did F VIII-RAg. In vessels completely occluded by tumour, examples of endothelial staining by UEA-1 in the absence of F VIII-RAg staining were found, but some such vessels appeared to lack surviving endothelial cells and in these no staining occurred. It is concluded that UEA-1 lectin is a more reliable endothelial marker in this setting than F VIII-RAg and may assist the demonstration of vascular invasion in these tumours.

Adenocarcinoma↗
PubMed1985

Monoclonal antibodies to blood group isoantigens: an alternative marker to factor VIII related antigen for benign and malignant vascular endothelial cells.

Monoclonal antibodies to A, B and H blood group isoantigens (BGI) were used in an indirect immunoperoxidase technique to compare the distribution of BGI expression as a marker of vascular endothelial cells with that of coagulation factor VIII related antigen (F VIII-RAg), a well established marker for vascular endothelium. Formalin-fixed and paraffin-embedded material from 70 specimens representing a wide range of reactive and benign or malignant neoplastic states of the vascular endothelium was used to provide adjacent serial tissue sections to compare directly the tissue expression of BGI and of F VIII-RAg. In reactive and benign neoplastic conditions of the vascular endothelium, cell membrane expression of the BGI appropriate to the patient's blood group was readily detected. In the more cellular and proliferative areas of some haemangiomas, pyogenic granulomas and cases of angiolymphoid hyperplasia with eosinophilia, BGI proved a superior marker of the endothelial cells compared with F VIII-RAg. The malignant endothelial cells of 27 specimens of angiosarcoma showed deletion of BGI expression in 24 and of F VIII-RAg in 19. Expression of neither antigen showed any significant correlation with the degree of tumour differentiation. Some cases of lymphangioma, uniformly negative for F VIII-RAg staining, showed strong expression of BGI. The possible use of BGI expression as a marker of vascular endothelium is discussed in the light of the known tissue expression of F VIII-RAg.

Angiolymphoid Hyperplasia with Eosinophilia↗
PubMed1985

Monoclonal antibodies to detect A, B and H blood group isoantigens in superficial transitional cell carcinoma of the bladder: a means of predicting invasive recurrences.

Monoclonal antibodies to A, B and H blood group isoantigens (BGI) have been used in an indirect immunoperoxidase technique to study the expression of BGI in both normal and malignant transitional epithelium in patients of all blood groups. BGI was detectable in all 15 biopsies of normal transitional epithelium and in 28 of 50 (56%) stage pTa and pTl transitional cell carcinomas of the bladder (TCCB). In the tumours failing to express BGI there was a 55% invasive recurrence rate at 5 years compared with 14% in those tumours expressing BGI. The difference was significant at the P less than 0.01 level. The recent availability of a monoclonal antibody to H isoantigen expressed in group O patients, in addition to monoclonal anti A and anti B, has made possible the inclusion of patients of all blood groups into a study using a standard immunoperoxidase technique without the need for specially processed biopsy material. The advantages of this technique compared with the earlier methods are discussed with reference to its possible role in identifying those patients at highest risk of developing invasive recurrence of their tumour.

ABO Blood-Group System↗
PubMedDate not supplied

Fractal geometric analysis of the renal arterial tree in infants and fetuses.

Fractal geometry is a useful method of quantitating the space-filling properties of complex objects and has a particular advantage in pediatric pathology because it is independent of organ size. The fractal dimensions of angiographic images of 44 renal arterial trees from 23 consent pediatric autopsies were measured by the box-counting method. The mean fractal dimension was 1.64 and all values were greater than the topological dimension (one), indicating that the renal arterial tree in fetuses and infants has a fractal element to its structure. There was no significant association with size of the kidneys, confirming the size-independent nature of the fractal dimension. There was no significant association with age of the subject, and the mean value was not significantly different from values obtained in studies of adult kidneys, suggesting that the degree of branching, at a lobar and lobular level, does not increase after about the 21st week of gestation. The results are compatible with a diffusion-limited aggregation model of development.

Adult↗