Frequent ALK rearrangement and TTF-1/p63 co-expression in lung adenocarcinoma with signet-ring cell component.

摘要: Primary adenocarcinoma with signet-ring cell component (Ad-SRCC) of the lung has been well characterized clinicopathologically and histologically, but their genetics rarely investigated. A recent report suggesting an association between Ad-SRCC EML4-ALK fusion prompted us to undertake a histological, immunohistochemical, molecular analysis 10 cases primary identified out 699 adenocarcinomas (1.4%). Most Ad-SRCCs showed characteristic architectural as cytological features including cohesive clustering cells, solid/acinar growth pattern, alveolar filling at tumor periphery. Diffuse co-expression TTF-1 p63 was observed in half Ad-SRCCs, this immunoprofile not recognized previously. Four (40%) harbored ALK translocations detected by reverse-transcriptase polymerase chain reaction, fluorescence situ hybridization, immunohistochemistry. One new variant identified. ALK-rearranged focal squamous differentiation. None present had EGFR or KRAS mutations, regardless status. This study successfully utilized histology alone identify subset showing high rate translocation. The histology, immunoprofile, frequent translocation, total lack may suggest that forms histologically/molecularly coherent subgroup adenocarcinoma.