Table 1.

Immunohistochemical analysis

Immunohistochemical marker		Results	Ref.
IMP3	Insulin-like growth factor II mRNA-binding protein 3	IMP3 is more frequently expressed in UPSC and CCC than in EEC (resp. 78 %, 57 % and 15 % of the tumours were positive).	[21]
P53		P53 is more expressed in non-endometrioid endometrial carcinomas than in EEC. Expression is also related to higher tumour grade.	[19]
ER and PR	Oestrogen and progesterone receptor	Negative receptors were associated with lymph node metastasis and decreased survival. ER and PR expression is lower in non-endometrioid endometrial carcinomas than in EEC.	[20, 34]
MLH1	MutL homolog 1	Loss of expression of mismatch repair proteins is seen in high grade EEC and not in UPSC and CCC. Loss of MLH1 expression is associated with longer survival.	[35, 36]
PTEN	Phosphatase and tensin homologue	PTEN positivity is more frequently found in UPSC than EEC.	[19]
Beta-catenin		Positive beta-catenin expression is associated with decreased stage, decreased grade and negative lymph node status	[37]
P16		Loss of p16 expression is significantly correlated with high FIGO stage and serous and clear cell histological subtype.	[38]
Ki-67		Higher Ki-67 expression is associated with higher tumour grade. UPSC and CCC show higher Ki-67 proliferation index than EEC.	[34]
Stathmin		Stathmin overexpression was associated with non-endometrioid histology, high grade and poor disease-specific survival.	[39]
ARID1A	AT-rich interactive domain 1A gene	Loss of ARID1A expression is significantly more frequent in high grade EEC compared to UPSC.	[40]
L1CAM	L1 cell adhesion molecule	L1CAM is associated with higher grade and non-endometrioid histology. Moreover, L1CAM positive EC have statistical significant poorer disease-free survival and overall survival.	[22]

UPSC = Uterine papillary serous carcinoma; CCC = Clear Cell Carcinoma; EEC = Endometrioid endometrial carcinoma; EC = endometrial carcinoma; FIGO = Fédération Internationale de Gynécologie et d’Obstétrique