Secretoneurin in bronchopulmonary carcinoids--immunohistochemical comparison with chromogranins A and B and secretogranin II.

Ninety-nine classical and 11 atypical bronchopulmonary carcinoids were investigated immunohistochemically with an antibody against secretoneurin, a peptide proteolytically processed from secretogranin II (chromogranin C), as well as antibodies against chromogranin A and B and secretogranin II. Secretoneurin was immunolocalized in 86 tumours (78 classical and eight atypical carcinoids); secretogranin II was found in the same tumours in a similar distribution, whereas chromogranin A was present in all 100 and chromogranin B in 106 tumours investigated. Bronchopulmonary carcinoids are usually not associated with clinically or biochemically distinct syndromes. Although we found bronchial carcinoids with different immunohistochemical chromogranins/secretogranin patterns, no correlation with the biological behaviour of these tumours could be demonstrated.