. Author manuscript; available in PMC: 2016 Jun 24.

Published in final edited form as: Mod Pathol. 2015 May 29;28(8):1023–1032. doi: 10.1038/modpathol.2015.60

Table 3.

Immunohistochemical findings in combined squamous cell and neuroendocrine carcinoma

Case no.	CM2B4	P53 (nuclear)		P63(nuclear)		Neurofilament		Cytokeratin 20		RB1

Part	Both	SCC	NET	SCC	NET	SCC	NET	SCC	NET	Both
1	Neg	Pos	Pos	Pos	Pos	Neg	Pos	Pos^a	Pos	Neg
2	Neg	Pos	Neg	Pos	Neg^b	Neg	Neg	Neg	Neg	Neg
3	Neg	Pos	Pos	Pos	Pos	Neg	Pos^a	Neg	Neg	Neg
4	Neg	Pos	Pos	Pos	Neg	Neg	Neg	Pos^a	Pos	Neg
5	Neg	Pos	Pos	Pos	Pos	Neg	Neg	Neg	Both^***	Neg
6	NA	Pos	Pos	Pos	Neg	Neg	Neg	Neg	Neg	Neg
7	NA	Pos	Pos	Pos	Neg	Neg	Neg	Neg	Neg	Neg
8	NA	Pos	Neg	Pos	Neg	Neg	Neg	Pos	Pos	Neg
9	NA	Pos	Pos^a	Pos	Neg	Neg	Pos^a	Pos^a	Pos	Neg
10	NA	Pos	Pos	Pos	Neg	Neg	Neg	Neg	Pos	Neg
% Pos	100	100	80	100	30	0	30	40	60	0

Abbreviations: NET: neuroendocrine tumor component, RB1: retinoblastoma 1, SCC: squamous cell carcinoma.

^****

One scalp tumor was CK20 positive; the other was CK20 negative (primary vs metastasis unknown).

Denotes focality.

Denotes negative in poorly differentiated areas.