[Carcinoid tumorlets and pulmonary hypoxia].

Relationship between carcinoid tumourlets and chronic pulmonary hypoxia was studied on a group of 29 patients coming to necropsy (25 cases) in the last 25 years or surgically treated (4 cases) for non-neoplastic pulmonary lesions. All tumourlets expressed the argyrophilia and were immunoreactive for neurone-specific enolase. Pulmonary hypoxia was studied according to the presence of chronic bronchitis, emphysema and microscopical signs of hypoxic arteriopathy. Cigarette smoking was an additional criterion. The results indicated a strong relationship between tumourlets and chronic pulmonary hypoxia. 79% of patients with tumourlets have had the emphysema and in 41% of examined cases with this lesion the chronic bronchitis was diagnosed. The hypoxic arteriopathy was present in 48% of subjects with emphysema and 27% of cases with bronchitis. It was found in the same number of patients with both the examined lung diseases. On the other hand, the possibility of other cause of neuroendocrine cell hyperplasia was to be considered in 17% of investigated subjects in whom no evidence for the above mentioned relationship was found.