High-intermediate risk endometrial cancer: Can gene expression predict recurrence?

Abstract

5591 Background: Studies have shown that adjuvant therapy increases progression free survival, but does not affect overall survival in patients with high-intermediate risk (H-IR) endometrial cancer (EMCA). Our objective was to develop a gene expression signature that may help identify H-IR EMCA patients with the highest risk of recurrence to help guide treatment strategies. Methods: Data was collected on all patients that met H-IR EMCA criteria diagnosed between 2000-2010 at UAB (n = 292). Of the patients that did not receive adjuvant treatment, 13 patients that recurred were matched to 13 patients that did not recur and original tumor was compared. Of those that recurred, 5 patients had original and recurrent tumor available for analysis. Gene expression data was collected using the Nanostring nCounter PanCancer Pathway 770 gene panel. Data was analyzed using nSolver Advanced Analysis Software. A fold change (FC) of ≥ ± 2 (p < 0.05) was used to identify genes with a significant expression difference. Results: Comparing the 13 patients that recurred to the 13 that did not, there were 5 genes with FC ≥ +2: BAIAP3, PLCB1, IL1R1, NOS3 and RAD50. There were 29 genes with FC ≥ -2; the top 3 genes with decreased expression (FC ≥ -10) were: BMP7, FGF18, WNT7A. Genes in the Cell Cycle (CC) pathway were significantly different in the patients that recurred (p = 0.02). There were 61 genes with FC ≥ +2 when comparing the original tumor to recurrent tumor; the top 3 genes with increased expression (FC ≥ 10) were: FGF18, CCND1, HIST1H3H (p < 0.05). There were 50 genes with FC ≥ -2; the top 3 genes with decreased expression (FC ≥ -1000) were: HOXA11, LEFTY2 and SFRP4. Wnt, Hedgehog, Chromatin Modification, DNA repair, TGF-β, MAPK, and CC pathways were significantly different in the recurrent samples compared to the original tumor (p < 0.05). Conclusions: Our data suggests that gene expression panels could better identify patients that warrant adjuvant treatment. The CC pathway, which is significantly different in the original tumor from those that recurred and those that did not, was further altered in the recurrent tumor samples. Additional studies are on-going to validate these findings and to further investigate DNA mutation differences in larger cohort of patients.