Insulinoma-associated protein 1 is a sensitive and specific marker for lung neuroendocrine tumors in cytologic and surgical specimens

Insulinoma-associated protein 1 (INSM1) is an immunohistochemical marker for neuroendocrine differentiation with potentially superior sensitivity and specificity. INSM1 performance in pulmonary cytology cell block material (CB) has not been well established, and large series demonstrating its performance have been few. Typical and atypical carcinoid, small cell lung carcinoma, and large cell neuroendocrine carcinoma, squamous cell carcinoma, and...