Dual Immunostain With SATB2 and CK20 Differentiates Appendiceal Mucinous Neoplasms From Ovarian Mucinous Neoplasms.
OBJECTIVE
Determination of the primary site of origin for mucinous neoplasms identified in the peritoneal and/or pelvic cavities may be challenging, with major differential diagnoses including appendiceal mucinous neoplasm (AMN) and ovarian mucinous neoplasm (OMN). Special AT-rich sequence binding protein 2 (SATB2) has been shown to be highly selectively expressed in the lower gastrointestinal tract, including the appendix.


METHODS
We investigated the utility of a dual stain (DS) with SATB2 or caudal type homeobox 2 (CDX2) and cytokeratin 20 (CK20) or villin in distinguishing AMNs from OMNs. Tissue microarrays with 40 AMNs and 18 OMNs were stained with SATB2 or CDX2 paired with either CK20 or villin.


RESULTS
SATB2 single stain showed a good sensitivity of 83% and the highest specificity of 78% for AMNs over OMNs among all four stains. DS with SATB2 and villin showed an identical sensitivity of 78% but specificity increased to 94%, while DS with SATB2 and CK20 showed a sensitivity of 80% and a specificity of 100%. In contrast, DS with CDX2 and CK20/villin showed slightly higher sensitivity but much lower specificity.


CONCLUSIONS
DS with SATB2/CK20 shows the greatest potential clinical utility in distinguishing AMNs from OMNs and is superior to DS with CDX2/CK20. Importantly, DS could be helpful for specimens with limited tissues.
Department of Pathology.
Zaibo
Z
Li
Department of Pathology.
Rachel
R
Roth
Department of Pathology.
Jonathan B
JB
Rock
Center for Biostatistics, The Ohio State University, Columbus.
Amy
A
Lehman
Department of Pathology.
William L
WL
Marsh
Department of Pathology.
Adrian
A
Suarez
Department of Pathology.
Wendy L
WL
Frankel
D002288:Adenocarcinoma, Mucinous / Q000175:diagnosis*; D001063:Appendiceal Neoplasms / Q000175:diagnosis*; D014408:Biomarkers, Tumor / Q000032:analysis*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D053554:Keratin-20 / Q000032:analysis / Q000096:biosynthesis; D036961:Matrix Attachment Region Binding Proteins / Q000032:analysis* / Q000096:biosynthesis; D010051:Ovarian Neoplasms / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D046888:Tissue Array Analysis; D014157:Transcription Factors / Q000032:analysis* / Q000096:biosynthesis
D014408:Biomarkers, Tumor; C507499:KRT20 protein, human; D053554:Keratin-20; D036961:Matrix Attachment Region Binding Proteins; C521297:SATB2 protein, human; D014157:Transcription Factors
Appendiceal mucinous neoplasm; CDX2; CK20; Dual immunostain; Ovarian mucinous neoplasm; SATB2; Villin