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M Lundqvist

Publications and source records attributed to M Lundqvist.

At least 55 records · Page 3Linked to original sources

S-100 protein in carcinoid tumours of appendix.

A series of 12 carcinoid tumours of the appendix were examined with regard to S-100 protein immunoreactivity. All tumours were both argentaffin and argyrophil, and displayed immunoreactivity after application of a monoclonal antibody against serotonin. The S-100 protein immunoreactivity appeared in 11 of the 12 tumours, preferably in cells presumably of Schwann cell origin with long slender processes localized at the periphery of the carcinoid tumour buds. Immunoreactive cells with cytoplasmic processes were also seen extending between individual tumour cell in the tumour aggregates. In a few tumours S-100 immunoreactivity occurred in the cytoplasm of tumour cells with or without cytoplasmic extensions. The presence of S-100 protein immunoreactive cells, apparently as an integral component, and its shape and distribution indicate that the peripheral nervous system (PNS) is histogenetically involved in the development of carcinoid tumours of the appendix.

Appendix↗

Neuron-specific enolase in mucosal endocrine cells and carcinoid tumours of the small intestine: a comparative study with neuron-specific enolase immunocytochemistry and silver stains.

Endocrine cells of human small intestinal mucosa, small intestinal carcinoids and carcinoid liver metastases were stained with an immunocytochemical technique using an antiserum against neuron-specific enolase (NSE), with the argyrophil technique of Grimelius and with the argentaffin technique of Masson. In the normal mucosa, scattered NSE-immunoreactive cells were seen mainly in the deeper parts of the crypts. These cells, as shown in the same sections, corresponded to the argentaffin and/or argyrophil cells indicating that they were of endocrine type. All intestinal carcinoids (16 cases) displayed NSE immunoreactivity. However, this reaction did not correlate on the cellular level with the silver techniques employed. Thus, many tumour cells were NSE immunoreactive but lacked an argentaffin or argyrophil reaction and vice versa. On the light microscopical level the silver techniques reveal the presence of neurohormonal granules in the tumour cells, while the NSE immunoreactivity appears to disclose neuroendocrine differentiation of the tumour cells irrespective of their hormone and granular content. Out of 13 carcinoid liver metastases, eight displayed strong NSE immunoreactivity, three were weakly stained and two were unreactive. Consecutive or the same tumour sections showed an argentaffin and argyrophil reaction in all carcinoid metastases. Since silver staining provides one type of information and NSE immunocytochemistry another, they provide in combination a good discriminator for neuroendocrine tumours.

Carcinoid Tumor↗

Small intestinal chromaffin cells and carcinoid tumours: a study with silver stains, formalin-induced fluorescence and monoclonal antibodies to serotonin.

The enterochromaffin cells of the human small intestinal mucosa were stained immunocytochemically with monoclonal antibodies against serotonin. The staining results were compared with those obtained with other methods for identifying serotonin-containing endocrine cells such as the argentaffin reaction, formalin-induced fluorescence and the argyrophil reaction of Grimelius. The different techniques gave similar, but not identical, results. The serotonin-immunoreactive cells outnumbered the argentaffin cells by 7%. Almost all (99%) serotonin-immunoreactive cells showed formalin-induced fluorescence but only a small population (5%) were fluorescent. In a subsequent study, these techniques were applied to 14 small intestinal carcinoids. It was shown that formalin-induced fluorescence and the argentaffin reaction were positive in 14 and 13 tumours, respectively, while the monoclonal serotonin antibodies failed to stain seven of the tumours. It is concluded that formalin-induced fluorescence and the argentaffin reaction are more useful techniques than serotonin immunocytochemistry for defining these tumours in routine formalin-fixed surgical specimens.

Carcinoid Tumor↗

Silver stains and immunocytochemical analysis with monoclonal serotonin antibodies for liver metastases of endocrine tumors. A study on percutaneous biopsy specimens.

With the aid of ultrasonography, representative percutaneous biopsy specimens were obtained from 20 of 21 patients (95 percent) with liver metastases of carcinoids and endocrine pancreatic tumors. The specimens were examined with silver stains and immunocytochemically after the application of monoclonal serotonin antibodies. The Grimelius argyrophil silver nitrate stain was positive in all tumor metastases, demonstrating that they were of neurohormonal endocrine type. The argentaffin reaction stained 14 of 15 metastases of small intestinal carcinoids, whereas tumors with other primary sites were unreactive. Immunocytochemical analysis with monoclonal serotonin antibodies stained all metastases of small intestinal carcinoids, and the other endocrine tumor metastases were unreactive. With immunocytochemical analysis, optimal results were obtained in Bouin-fixed tumor specimens, whereas for the argentaffin reaction, formalin was preferable. The results show that silver stains and immunocytochemical analysis with monoclonal serotonin antibodies on small percutaneous biopsy specimens of liver metastases of endocrine tumors and carcinoids are valid for the prediction of the location of the primary tumors.

Adolescent↗

Polypeptide YY (PYY) and pancreatic polypeptide (PP) in rectal carcinoids. An immunocytochemical study.

The frequency and distribution of polypeptide YY (PYY) and pancreatic polypeptide (PP) immunoreactive tumour cells of 14 small intestinal and of 27 rectal carcinoids were studied. All small intestinal and 14 rectal tumours were unreactive to both hormones. However, 13 rectal carcinoids contained a variable number of PP-immunoreactive cells. In four of these cases both PYY- and PP-immunoreactive cells were seen. The PP-immunoreactive cells greatly exceeded the number of PYY-immunoreactive cells. Two rectal carcinoids with PYY and PP immunoreactivities, but not the rest of the tumours, reacted also with an antiserum specific to the C-terminus of PP. This indicates that most PP immunoreactive rectal carcinoids lack the C-terminus sequence of the PP molecule.

Carcinoid Tumor↗

Argyrophil reaction in rectal carcinoids.

The Grimelius argyrophil reaction was studied in 27 rectal carcinoids. A majority of the tumour cells were silver-reactive in 16 tumours and a minority in 11 tumours. Both weakly and strongly stained tumours were found, as well as tumour cells with variable staining properties within the same tumour. Re-staining resulted in potentiation of the reaction, but this was most obvious in tumours with an initially easily identified argyrophilia. It is suggested that evaluation of the Grimelius argyrophil reaction in combination with routine histology increases the accuracy of the diagnosis of rectal carcinoids.

Carcinoid Tumor↗

Exocrine and endocrine cell differentiation in small intestinal adenocarcinomas.

Sixteen adenocarcinomas of the small intestine were examined with respect to the ability of the the tumour cells to differentiate in exocrine and endocrine directions. Both intra- and extracellular mucous material was found in 14 tumors and lysozyme immunoreactivity, a characteristic of normal Paneth cells, was seen in scattered tumor cells in two cases. Three tumors contained a few argyrophil cells, indicating the presence of tumor cell population with endocrine production. In two of these tumors some tumor cells displaying an argentaffin reaction, a staining property characteristic of enterochromaffin cells storing serotonin, were also found. In one tumor examined electron microscopically, tumor cells with cytoplasmic zymogen granules were seen and also two different types of endocrine tumor cells containing neurosecretory hormone granules. The results show that the tumor cells of small-intestinal adenocarcinomas possess the ability to differentiate in both the exocrine and the endocrine direction.

Adenocarcinoma↗

Majority and minority cell populations in small-intestinal carcinoids.

A quantitative study of argentaffin and argyrophil cells in 12 typical small intestinal carcinoids was made. The tumours contained 20-74 per cent of argentaffin cells (mean, 59 per cent) and 11-64 per cent of argyrophil cells (mean, 28 per cent). Five to 37 per cent (mean, 13 per cent) were unreactive to both silver stains. The argentaffin cells constituted the majority cell population in all tumours except one, in which the argyrophil cells predominated. At electron microscopy, pleomorphic secretory granules of the enterochromaffin cell type were found in argentaffin tumour cells, while the argyrophil tumour cells contained round granules. The silver staining properties and the ultrastructural morphology of the small-intestinal carcinoids are consistent with the opinion that these tumours are multi-hormonal.

Adult↗