Quantification of Grimelius reaction in neuroendocrine tumors of the lung.

The authors have studied the percent area occupied by the Grimelius-positive cells in lung neuroendocrine tumors. The highest values were noted in typical carcinoid tumors: they decreased progressively in atypical carcinoids, small "oat cell" carcinoma and large cell carcinoma. There was, however, a large dispersion of values, especially in the groups of typical and atypical carcinoid tumors. The possible significance of these data in the diagnosis, evaluation of therapeutical results and prognosis is discussed.