Patterns of DNA distribution and neurohormone immunoreactivity in the tumour cells: tools for the histopathological assessment of gastro-intestinal carcinoids.

Modern immunohistochemical and DNA cytochemical analyses of gastro-intestinal carcinoids have yielded results that have increased our knowledge of the biological properties and the histogenesis of these theoretically and practically so fascinating kinds of neoplasm. Carcinoids in different anatomical localisations were found to show marked differences with regard to their neurohormone peptide immunoreactivity pattern and their ability to evoke clinical signs and symptoms of hormone overproduction. This can be of great help to the practising pathologist when he tries to predict the anatomical site of an unknown primary tumour from the results of this histopathological assessment of a metastatic nodule of a carcinoid. The DNA distribution pattern in the nuclei of carcinoid tumour cells is a tool in the histopathological assessment of the neoplasm that seems to be of some value in predicting the subsequent clinical course of the disease. This conclusion is based on the results of a pilot study of 8 cases of ileal carcinoids with liver and lymph node metastases. It was found that 4 cases with a rapidly progressive fatal disease had a higher proportion on non-diploid tumour cell nuclei than 4 cases still alive and at full work 5 years after the diagnosis of liver metastases. However, the number of aneuploid tumour cell nuclei was negligible in both groups.

Assessment of malignancy potential in so-called interval mammary carcinomas.

Forty-two so-called interval cancers of the breast were studied. The mammograms were reviewed and the tumors were classified as 14 'unrecognized', 9 'observer error', 1 'technical error' and 18 'true' interval cancers. By using a scoring system based upon histologic differentiation, axillary nodal status, estrogen receptor level, and nuclear DNA content, eight ductal carcinomas with high malignancy potential were identified. All of these tumors belonged to the group 'true' interval cancer. The data indicate that the mammographic subgroup 'true' interval cancer identifies the highly malignant tumors. However, even this strictly selected subgroup is heterogeneous since it also includes some tumors with low malignancy potential.