RT Journal Article
SR Electronic
T1 Aberrant anaplastic lymphoma kinase expression in high-grade pulmonary neuroendocrine carcinoma
JF Journal of Clinical Pathology
JO J Clin Pathol
FD BMJ Publishing Group Ltd and Association of Clinical Pathologists
SP 705
OP 707
DO 10.1136/jclinpath-2012-201329
VO 66
IS 8
A1 Nakamura, Harumi
A1 Tsuta, Koji
A1 Yoshida, Akihiko
A1 Shibata, Tatsuhiro
A1 Wakai, Susumu
A1 Asamura, Hisao
A1 Furuta, Koh
A1 Tsuda, Hitoshi
YR 2013
UL http://jcp.bmj.com/content/66/8/705.abstract
AB Aims In lung cancer with anaplastic lymphoma kinase (ALK) gene rearrangement, accurate diagnosis is essential to identify patients who can be treated with a specific kinase inhibitor. Sensitive ALK immunostaining can provide nearly complete concordance with gene rearrangement status and is expected to serve as a surrogate biomarker for tailored treatment with an ALK inhibitor. In the present report, we describe aberrant ALK expression in a small proportion of pulmonary neuroendocrine carcinomas (NECs) that do not have ALK gene alteration. Methods A total of 227 pulmonary NECs were assembled on tissue microarrays and were subjected to highly sensitive ALK staining methods. Results We observed focal positivity with heterogeneous intensity in 2 (2.9%) of 69 small-cell carcinomas and 1 (0.9%) of 106 large-cell NECs. In contrast, 52 carcinoid tumours were all negative for ALK expression. Neither ALK rearrangement nor amplification was observed using fluorescence in situ hybridisation, and no somatic mutation was detected in three ALK positive NECs. Conclusions Thus, this aberrant expression is probably of a wild-type ALK and a potential pitfall when implementing sensitive ALK immunohistochemistry in the molecular diagnosis of lung cancer.