Jonathan R. Salisbury

Demonstration of cytokeratins and an epithelial membrane antigen in chordomas and human fetal notochord.

The application of immunohistochcmical staining with anti-epithelial monoclonal antibodies to the differential diagnosis of chordomas is described. Cytokeratins and an epithelial membrane-specific oligosaccharidc sequence arc found in chordomas but not in chondrosarcomas or normal cartilage. The same cytokeratins and oligosaccharide sequence are demonstrated in human fetal notochord. Immunohistochemical staining with antiepithelial antibodies is therefore of value in distinguishing chordomas from cartilaginous tumours. The staining of notochord with the same monoclonal antibodies adds weight to the proposition that chordomas arise from embryonic rests of notochordal cells.

Immunohistochemical analysis of CDw52 antigen expression in non-Hodgkin's lymphomas.

AIM--To determine the antigen expression of CDw52 using Campath-1 antibodies in a series of non-Hodgkins lymphomas (NHLs). METHODS--Tissue sections of lymphoma were stained immunohistochemically using rat Campath-1G and humanised Campath-1H with avidin-biotin-peroxidase complex techniques. Fifty-two fresh frozen lymphomas and a further 26 paraffin wax embedded sections were studied. RESULTS--Thirty-seven out of 41 B cell lymphomas were positive with Campath-1H in frozen sections (low grade, 24 of 24; high grade, 13 of 17) as were three out of five T cell lymphomas. Reed-Sternberg cells in six cases of Hodgkins disease did not react. Eleven out of 16 high grade B cell lymphomas also stained positively with Campath-1G in paraffin wax sections as did five out of 10 T cell lymphomas. CONCLUSIONS--The Campath-1 antibodies showed that CDw52 antigen expression was present in all cases of low grade B cell NHL examined. Immunohistochemical staining in high grade B cell NHL and in T cell NHL was variable. These findings may be relevant to patient selection when considering treatment with Campath-1 antibodies.

Spectrum of clinical presentation, treatment and prognosis in a series of eight patients with leukaemia cutis

All types of leukaemia can disseminate to the skin, producing cutaneous deposits known as leukaemia cutis (LC). We undertook a retrospective study to review the clinical presentations, treatment and outcome of eight patients with LC managed in our department over a period of 12 years. The clinical phenotype varied, with erythematous papules and nodules occurring with greatest frequency. Infiltrated haemorrhagic plaques and perifollicular acneiform papules were also seen. Although patients were treated aggressively for their underlying leukaemia, and received therapy directed towards LC, they tended to be refractory to treatment and the diagnosis was generally associated with a poor prognosis. The exception was a patient with chronic lymphocytic leukaemia, who survived 3 years after developing LC.

Chemotherapy Effects on Hepatoblastoma: A Histological Study

The histopathological features of hepatoblastoma in 17 patients treated with preoperative chemotherapy were compared with those in 11 patients not subjected to chemotherapy during the same 11-year period. Tumor necrosis was more extensive in patients receiving preoperative chemotherapy. Two tumors, however, were apparently unaffected by chemotherapy. There was no obvious correlation between the extent of necrosis and the number of courses of chemotherapy. There also seems to be no evidence of preferential ablation of a particular morphological type of tumor. The most notable feature in cases treated with chemotherapy was the extensive presence of osteoid. Osteoid was present in 36% of untreated cases, occupying < 5% of the surface area, compared with 82% in the treated group. In seven cases, osteoid occupied > 40% of the surface area. This finding raises speculation about the role of chemotherapy in the maturation of tumors that have an inherent ability to differentiate. A longterm study is needed to clarify the prognostic significance of mature heterologous elements in hepatoblastoma

Cutaneous Rosai–Dorfman disease

We report a patient with purely cutaneous Rosai–Dorfman disease (RDD) who presented with a solitary, asymptomatic plaque on the back of her left thigh, with characteristic, large histiocytoid cells exhibiting emperipolesis histologically. Cutaneous lesions occur in 27% of patients with lymph node involvement in RDD however purely cutaneous disease has only been reported on 18 previous occasions. The aetiology is unknown, although it is thought to be a reactive disorder rather than neoplastic, possibly an immunological response to an infectious agent.

A Histomorphometric Study of Bone Changes in Thyroid Dysfunction in Rats

Clinical studies in thyrotoxicosis reveal a state of high bone turnover leading, eventually, to osteoporosis. Recently there has been concern that thyroxine (T4) treatment may have a similar effect on bone. Rat models have been used to study the effects of T4 on bone, but the majority of studies have looked at the effects of T4 after only 3 weeks of treatment. The aim of this study was to evaluate histomorphometric changes in rats after 12 weeks of thyroxine overtreatment or 12 weeks of hypothyroidism compared with untreated control animals. Animals received either T4 200 micrograms/kg per day, 0.1% propylthiouracil, or vehicle for 12 weeks. Tetracycline was administered 1 week and 3 weeks prior to killing. Iliac crest bone was used for histomorphometry. Serum T4 measurements (taken at killing) confirmed hyper- and hypothyroidism in the appropriate animal groups (between group difference p < 0.001 by ANOVA). In hyperthyroid animals there was an increase in mineral apposition rate (MAR; 0.94 vs. 0.59 microns/day, p < 0.001) and mineral formation rate (MFR/BS; 0.24 vs. 0.12 x 10(-2) micron3/micron2 per day, p < 0.001) and a slight increase in eroded surfaces (ES/BS%; 1.54 vs. 1.36, p < 0.05) compared with controls, consistent with previous in vitro and in vivo observations. In hypothyroid rats there was a marked reduction in osteoid surfaces (OS/BS%; 1.7 vs. 24.8, p < 0.001) and MAR (0.3 vs. 0.59 micrograms/day, p < 0.001), a reduction in ES/BS% (0.51 vs. 1.36, p < 0.05), and an increase in cancellous bone volume (BV/TV%; 30.29 vs. 19.6, p < 0.05), suggesting that thyroid hormones are a requirement for normal bone turnover.(ABSTRACT TRUNCATED AT 250 WORDS)

A20 RNA expression is associated with undifferentiated nasopharyngeal carcinoma and poorly differentiated head and neck squamous cell carcinoma

A20 is an anti‐apoptotic gene that can be induced in human epithelial cell lines in response to expression of the Epstein–Barr virus (EBV) gene product latent membrane protein 1 (LMP1). EBV is a ubiquitous, persistent human herpesvirus that is consistently associated with undifferentiated nasopharyngeal carcinoma (NPC), in which antigen expression includes LMP1. Consistent with a potential role in the development of NPC, LMP1 has profound effects on epithelial cell growth. A20 may be a key downstream effector of LMP1 in NPC, as LMP1‐induced A20 blocks p53‐mediated apoptosis in H1299 epithelial cells and most NPCs have wild‐type p53. Moreover, the potential role of A20 in the development of epithelial malignancies may extend to tumours not associated with EBV. The purpose of this study was to develop an in situ hybridization assay to assess expression of A20 RNA in undifferentiated NPC and in non‐EBV‐associated poorly differentiated head and neck squamous cell carcinomas (SCCs) and well‐differentiated SCCs of the skin. A20 RNA expression was also examined in normal samples of oral mucosa and skin. Expression of A20 was demonstrated in 76 per cent of undifferentiated NPCs and in 80 per cent of poorly differentiated head and neck SCCs, suggesting a role for A20 in the pathogenesis of these epithelial malignancies. By contrast, A20 RNA was not detected in well‐differentiated SCCs of the skin, or in any normal samples of squamous epithelial tissue. The pathway leading to A20 expression in non‐EBV‐associated poorly differentiated head and neck SCCs is clearly LMP1‐independent. LMP1 expression was demonstrated in 29 per cent of NPC biopsies, suggesting an LMP1‐independent pathway to A20 induction in undifferentiated NPC. Copyright

Epstein-Barr virus latent membrane protein does not inhibit differentiation and induces tumorigenicity of human epithelial cells

Latent membrane protein (LMP) is a latent Epstein-Barr virus (EBV) protein expressed in the EBV associated malignancy, nasopharyngeal carcinoma (NPC). Properties ascribed to this protein include inhibition of epithelial cell differentiation and deregulation of epithelial cellular gene expression, and are believed to contribute to the development of NPC. Studies to evaluate the oncogenic potential of LMP in epithelial cells have not been conclusive. We carried out studies to determine the tumorigenic activity of LMP in two human epithelial cell lines, SCC12F and HaCaT; while SCC12F LMP transfectants were non-tumorigenic in severe combined immunodeficient mice, HaCaT LMP transfectants were strongly oncogenic. The tumours produced were well differentiated, keratinising squamous cell carcinomas suggesting that LMP does not inhibit epithelial cell differentiation which conflicts with a previous report by Dawson et al. (1990). To resolve this discrepancy we examined the ability of HaCaT and SCC12F LMP transfectants to differentiate in a suspension culture assay. Both lines were able to differentiate to a similar extent as parental lines and control transfectants. Our results indicate that LMP is strongly oncogenic in human epithelial cells but that inhibition of differentiation is not necessarily a mechanism by which LMP contributes to the pathogenesis of NPC.

Cutaneous manifestations of granulocyte colony-stimulating factor.

Granulocyte colony‐stimulating factor (GCSF) is a recombinant human growth factor widely used in haematology. It is known to cause cutaneous vasculitis and neutrophilic dermatoses. We present three cases of Sweets syndrome (SS) associated with GCSF use. Raised GCSF levels have been demonstrated in patients with SS. GCSF is the best understood mechanism by which neutrophil accumulation occurs and shows a dose‐dependent effect in provoking SS.

CASTLEMAN'S DISEASE IN CHILDHOOD AND ADOLESCENCE: Report of a Case and Review of Literature

Cases of Castlemans disease, a disorder affecting lymphoid organs, which is largely benign in nature, are rare in the pediatric period. This report describes one such case, occurring in a 5-year-old boy, and reviews the published cases of Castlemans disease presenting in childhood and adolescence. The purpose of this review was to compare the features of this disease process in children with the much fuller documentation that exists for Castlemans disease in adults. In children, Castlemans disease usually presents in the abdomen, chest (mediastinum or lung hilum), or neck and may be either asymptomatic or present with systemic symptoms of which anemia and fever are the most frequent. The disease is curable by surgical excision.