Value of circulating tumor cells positive for thyroid transcription factor-1 (TTF-1) to predict recurrence and survival rates for endometrial carcinoma.

PURPOSE: This study was conducted to analyze the predictive value of circulating tumor cells (CTC) expressing thyroid transcription factor-1 (TTF-1) on the recurrence and survival rates of endometrial carcinoma patients treated with laparoscopic surgery.

METHODS: 78 patients were recruited, diagnosed with endometrial carcinoma and measured CTC expressing TTF-1 using flow cytometry in blood and tissues. Then, the patients were distributed into TTF-1-positive (N=42) and -negative (N=36) groups. The levels of HE4 were determined by ELISA, the levels of cancer antigen CA125 and CA15.3 by chemiluminescent immunoassay, and the levels of mRNA expression of survivin, β-catenin, miR-15a, and PTEN by RT-PCR assay from endometrial carcinoma samples.

RESULTS: Patients in TTF-1-positive group had mainly TNM stages II and III-IV, whereas the TTF-1-negative group stages I and II predominated. The rates of vascular infiltration and lymphatic metastasis in the TTF-1-positive group were higher compared with the TTF-1-negative group (p<0.05). The serum levels of CA125, CA15.3, and HE4 were significantly higher in the TTF-1-positive group than in the TTF-1-negative group (p<0.05). The levels of survivin and β-catenin mRNA expression in endometrial carcinoma in the TTF-1-positive group was higher than in the TTF-1-negative group. In contrast, the levels of miR-15a and PTEN mRNA expression were lower in the TTF-1-positive group (p<0.05). The median follow-up duration was 25 months for both groups. At that time, progression-free survival (PFS) and the median survival time decreased in the TTF-1-positive group compared with the TTF-1-negative group. Additionally, the recurrence rate increased in the TTF-1-positive group.

CONCLUSION: The rate of TTF-1-positive CTC was strongly correlated with TNM staging, vascular infiltration, lymphatic metastasis, and the levels of CA125, CA15.3, and HE4 in endometrial carcinoma. The levels of survivin, β-catenin, miR-15a, and PTEN mRNA also contributed to predict survival rates after laparoscopic surgery.