VOLUME FRACTION OF DENSE-CORE GRANULES CORRELATES STRONGLY WITH SURVIVAL IN DISSEMINATED (STAGE-IV) NEUROENDOCRINE CELL CARCINOMAS OF THE LUNG OF THE WELL-DIFFERENTIATED AND SMALL-CELL SUBTYPES

In order to verify whether ultrastructural quantitative morphological indices of neuroendocrine cell carcinoma of the lung may help to predi ct survival in disseminated disease (Stage IV), 21 biopsy specimens we re studied. Volume density of mitochondria and dense-core granules was assessed by a conventional point-counting procedure. Survival in mont hs after biopsy was considered the dependent variable of age and of th e morphometric parameters, in a multivariate linear regression analysi s. The significance level was set at 5%. Survival was positively corre lated ip = 0.011, multiple r = 0.686) with volume fraction of dense-co re granules (p = 0.0025) and negatively correlated with volume fractio n of mitochondria (p = 0.035), and also with age (p = 0.034). Our data indicate that survival is strongly dependent on the degree ofneuroend ocrine differentiation and of metabolic activity of tumour cells and t hat improved prognostic accuracy is provided by the use of quantitativ e analyses as compared with the conventional subtyping of malignant pu lmonary neuroendocrine neoplasms.