For large cell neuroendocrine carcinoma, CD56 (92%) and synaptophysin (88%) were more sensitive than INSM1 (75%), while chromogranin was less sensitive (46%).
The SSP was developed in 68 NSCLC tumors of adenocarcinoma (AC), squamous cell carcinoma (SqCC) and large-cell neuroendocrine carcinoma (LCNEC) histology, based on NanoString expression of 11 (CHGA, SYP, CD56, SFTPG, NAPSA, TTF-1, TP73L, KRT6A, KRT5, KRT40, KRT16) relevant genes for IHC-based NSCLC histology classification.
Using the Dutch pathology registry (PALGA), surgically resected LCNEC with matching pre-operative biopsy specimens were identified and haematoxylin and IHC slides (CD56, chromogranin-A, synaptophysin) requested.
The pathology report revealed a large cell neuroendocrine carcinoma with numerous implants in perirectal adipose tissue and lymph metastasis in 2 lymph nodes (pT4aN1b), positive for synaptophysin, chromogranin and CD 56 with proliferation index Ki-67 50%.