[Rare histological type of pulmonary adenocarcinoma--two clinical cases]

Two cases of primary signet-ring cell adenocarcinoma of the lung are presented. The patients were: a 53-year-old man with a left lung mass and a 40-year-old woman with a right lung mass. Endobronchial biopsy performed after fiber-bronchoscopy reveal this rare histological type for pulmonary localizations of neoplasms. It is well known that this histological type is found in digestive localizations of neoplasms, especially gastric, but in these two cases we excluded such a neoplasm. The tumor we found in these two cases is a very rare intrapulmonary neoplasm with a poor clinical course and prognosis. Signet-ring cell adenocarcinoma is a recently described neoplasm whose histology is different from most lung adenocarcinomas and represented a spectrum of malignant potential. Little is known of the behaviour of more malignant subtype.