Pulmonary blastoma with neuroendocrine differentiation in cell morules resembling neuroepithelial bodies

Pulmonary blastoma is an infrequent malignant neoplasm, so called because of its resemblance to fetal lung. The original description outlined the components as variable mixtures of epithelial and stromal elements. More recently, a variant displaying almost exclusively epithelial differentiation has been described. We report our findings in a case of pulmonary blastoma with predominance of epithelial cells, forming tubular structures and large morules. The architectural arrangement of the morules was remarkably similar to normal bronchial neuroepithelial bodies. Moreover, their immunohistochemical profiles were also very similar, including the expression of cytokeratins, chromogranin, neuron-specific enolase, synaptophysin, gastrin, calcitonin, bombesin, somatostatin and serotonin.