Comprehensive Histologic Analysis of ALK-Rearranged Lung Carcinomas

• DOI: 10.1097/pas.0b013e3182233e06
• Publication Date: 2011-07-13T15:34:06Z
• Authors: Akihiko Yoshida; Koji Tsuta; Harumi Nakamura; Takashi Kohno; Fumiaki Takahashi; Hisao Asamura; Ikuo Sekine; Masashi Fukayama; Tatsuhiro Shibata; Koh Furuta; Hitoshi Tsuda
• Keywords: Signet ring cell; Pleomorphism (cytology)

A subset (1% to 5%) of non-small-cell lung carcinomas harbors the EML4-ALK fusion gene. Data from previous studies on histomorphology ALK-rearranged cancer are inconsistent, and specific histologic parameters that characterize this how accurately such predict underlying ALK abnormality remain uncertain. To answer these questions, we performed a comprehensive analysis 54 surgically resected, extensively sampled compared them with 100 consecutive resections ALK-wild-type cancers. All cases showed at least focal adenocarcinoma component, 3 2 had additional squamous sarcomatoid differentiation, respectively. Solid or acinar growth pattern, cribriform structure, presence mucous cells (signet-ring goblet cells), abundant extracellular mucus, lack lepidic growth, significant nuclear pleomorphism were more common in ALK-positive Two recognizable constellations findings, solid signet-ring cell pattern mucinous present focally majority (78%) tumors, but rare (1%) ALK-negative tumors. Multivariate combination patterns was most powerful indicator rearrangement. Characteristic histologies both primary sites metastases. Thus, findings may help identify for testing. However, none completely sensitive rearrangement, should not replace confirmatory molecular immunohistochemical studies. cancers commonly coexpression thyroid transcription factor-1 p63, its significance is currently unclear.