Serous versus high-grade endometrioid endometrial carcinoma: immunohistochemistry of RFP is not useful for differentiation.
We evaluated the immunohistochemical expression of ret finger protein (RFP) along with conventional immunohistochemical markers in endometrioid and serous carcinomas of the endometrium. A total of 124 endometrial carcinoma cases (24 grade 1 endometrioid, 60 grade 3 endometrioid, 40 serous) were retrieved from pathology archives. Tissue microarrays were constructed. The expression of RFP, WT1, ER, PR, p53 and p16 was examined immunohistochemically. Sensitivity, specificity, area under the receiver operating characteristic (ROC) curve,  statistic for interobserver reproducibility, Kruskal-Wallis test, Mann-Whitney U test and Fisher's exact tests were performed for statistical analyses. The mean RFP score was 1.54 in grade 1 endometrioid, 4.31 in grade 3 endometrioid, and 6.31 in serous carcinomas (p < 0.001). Overall, RFP scores were higher both in serous and grade 3 endometrioid carcinoma (p > 0.05), and significantly lower in grade 1 endometrioid carcinoma (p < 0.05). p16 and p53 staining patterns were able to differentiate between high-grade endometrioid and serous carcinoma (p < 0.001). ER, PR and WT-1 did not reach statistical significance for subtyping. The  values of the general agreement between the observers were 0.737 and 0.727 for endometrioid and serous carcinomas respectively (p < 0.001). Diffuse p53 and p16 staining provides the most sensitive and specific immunomarkers for differentiating high-grade endometrioid and serous carcinomas.
Department of Pathology, Hacettepe University, Ankara, Turkey.
Cigdem
C
Ussakli
Department of Pathology, Hacettepe University, Ankara, Turkey. alpusubutun@yahoo.com.
Alp
A
Usubutun
Department of Pathology, Ankara Atatürk Training and Research Hospital, Ankara, Turkey.
Nazmiye
N
Dincer
Department of Biostatistics, Hacettepe University, Ankara, Turkey.
Anil
A
Dolgun
Department of Biostatistics, Hacettepe University, Ankara, Turkey.
Diilek
D
Bülbül
Department of Pathology, Etlik Zübeyde Hanim Research and Teaching Hospital, Ankara, Turkey.
Zuhal
Z
Isikdogan
Department of Pathology, Bas'kent University, Ankara, Turkey.
Nihan
N
Haberal
Department of Pathology, Bas'kent University, Ankara, Turkey.
Ozlem
O
Ozen
Department of Pathology, Hacettepe University, Ankara, Turkey.
Gaye Guler
GG
Tezel
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D014408:Biomarkers, Tumor / Q000032:analysis*; D018269:Carcinoma, Endometrioid / Q000175:diagnosis*; D018284:Cystadenocarcinoma, Serous / Q000175:diagnosis; D004268:DNA-Binding Proteins / Q000032:analysis*; D003937:Diagnosis, Differential; D016889:Endometrial Neoplasms / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009687:Nuclear Proteins / Q000032:analysis*; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D046888:Tissue Array Analysis; D000070584:Tripartite Motif Proteins
D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C064419:TRIM27 protein, human; D000070584:Tripartite Motif Proteins
 RFP;  endometrioid carcinoma;  immunohistochemistry;  serous carcinoma; endometrial neoplasms