Cell adhesion molecules and intermediate filaments on embryonal childhood tumors.

We describe the expression of 18 different cell adhesion molecules, intermediate filaments and Ki-67 antigen in embryonal childhood tumors. 5 microns frozen sections from 15 nephroblastomas, 13 neuroblastomas, six rhabdomyosarcomas, one Ewing sarcoma and one pulmonary blastoma were analyzed by the alkaline phosphatase anti-alkaline phosphatase (APAAP) method using murine monoclonal antibodies. All tumors exhibited high proliferation rates as did, surprisingly, the nephroblastoma specimens despite pre-treatment with chemotherapy. Polysialylated NCAM was demonstrated on all tumor types, but Ewing sarcoma and expression correlated inversely with cell differentiation. In contrast, E-cadherin was present solely on tubulus like cells in nephroblastomas. This cell type showed a coexpression of cytokeratin and vimentin, giving evidence of its intermediate position between the mesenchyme and epithelium. In neuroblastomas, CD44s (hyaluronate receptor) expression was increased with cell differentiation. ICAM-1, VCAM-1 and E-selectin were mostly expressed in regressive areas of pretreated nephroblastoma specimens where a considerable infiltration of leukocytes was noted as well. Since endothelial and leukocyte adhesion molecules were distinctly less expressed in all other tumors investigated, these findings may indicate immunological processes as a consequence of or as supplement to the chemotherapeutical effect on nephroblastoma cells. Integrin receptors were not found on the surface of tumor cells, and therefore, at least those investigated seem to be of secondary importance to the biology of the tumors studied herein. In conclusion, our investigations demonstrate that, besides achieving a secure and prompt differentiation between various embryonal tumors, applying the panel of monoclonal antibodies proposed herein gives interesting insights into the histogenesis, biology and metastatic potential of pediatric malignancies.

Polysialylated neural cell adhesion molecule in childhood ganglioneuroma and neuroblastoma of different histological grade and clinical stage.

BACKGROUND AND AIMS: Neuroblastoma cells express the polysialylated form of the neural cell adhesion molecule (PSA-NCAM), which normally becomes restricted to a few neural regions after embryogenesis. The aim of the present study was to evaluate PSA-NCAM as a marker in childhood neuroblastoma. PATIENTS/METHODS: We studied the expression of PSA-NCAM on tumor specimens and in sera of 27 children, altogether, with ganglioneuroma and neuroblastoma of different histological grades and clinical stages. For both methods, immunohistochemistry on 5-microm frozen sections and immunoluminescence serum assay, the polysialic-acid-specific monoclonal antibody 735 was used. RESULTS: PSA-NCAM expression was highest in patients with undifferentiated neuroblastoma and advanced stages of disease, whereas children with differentiated tumor types and low clinical stages had distinctly reduced or no reactivity in immunohistochemistry and, simultaneously, normal serum levels. PSA-NCAM expression correlated with other prognostic and diagnostic markers, such as MYCN gene amplification, and serum concentrations decreased during successful treatment. CONCLUSIONS: We conclude that PSA-NCAM, both immunohistochemically and in the serum, is a promising candidate for another useful diagnostic and prognostic tumor marker in childhood neuroblastoma.

[Expression of polysialylated NCAM on neuroblastomas of various histology and clinical stages]. / Expression von polysialyliertem NCAM auf Neuroblastomen unterschiedlicher Histologie und klinischer Stadien.

We studied the expression of the polysialylated form of the neural cell adhesion molecule (PSA-NCAM) on the surface of tumor cells and in the serum of 26 patients with neuroblastoma of different histological grades and clinical stages. For both methods, immunohistochemistry and chemiluminescence immunoassay, the plysialic acid specific monoclonal antibody 735 was used. We show that the expression of this NCAM form correlates with the histological differentiation, stage, other tumor markers and course of disease. PSA-NCAM expression seems to enhance the malignancy of neuroblastoma cells and their tendency to metastasis. Since PSA-NCAM serum concentrations correlate to the amount of PSA-NCAM positive tumor cells, we conclude that PSA-NCAM is a new useful diagnostic and prognostic marker for childhood neuroblastoma.

Benign papilloma of the cervix in childhood: immunohistochemical findings and review of the literature.

UNLABELLED: Papillomas of the genital region are rare benign tumours causing sanguineous vaginal discharge in prepubertal girls. We report on a papilloma of the cervix in a 2-year-old girl. We characterize the tumour immunohistochemically and give a brief review about the current literature. CONCLUSION: Genital tract papillomas are benign differentiated tumours of probable Müllerian origin with a good prognosis even after tumour recurrence. Local excision is adequate for treatment.