Abstract 461: Combined analysis of circulating epithelial cell count and serum thyroglobulin for differentiating disease status of the patients with papillary thyroid carcinoma

Abstract

Abstract Papillary thyroid carcinoma (PTC) is one type of thyroid cancer and accounts for about 80% of the cases. Routine surveillance by serum thyroglobulin (Tg) and medical imaging is the current practice to monitor disease progression of the patients. However, the presence of anti-Tg antibody or other influence factors may discount the value of serum Tg in disease monitoring. Whether enumeration of circulating epithelial cells (CECs) and its combined analyses with serum Tg help to define disease status of PTC patients was investigated. CECs were first enriched from the peripheral blood of the healthy control subjects (G1, n = 17) and the patients at disease-free status (G2, n = 26) or with distant metastasis (G3, n = 22). The number of CECs expressing epithelial cell adhesion molecule (EpCAM) was determined by immunofluorescence microscopy analyses. The medium number of EpCAM+-CECs was 6 (intequartile range 1-11), 12 (interquartile range 7-16) and 91 (interquartile range 31-206) cells/ml of blood for G1, G2 and G3, respectively. EpCAM+-CEC counts were significantly higher in G3 than in G1 (p<0.05) and G2 (p<0.05). Our data further revealed that combined analysis of serum Tg with EpCAM+-CEC defined the disease status (disease-free vs. distant metastasis) in 46 (95.8%) of the 48 patients with the AUC equivalent of 0.962 (p<0.0001) in the ROC analysis. The sensitivity and specificity of the assay was 100% and 92.3%, respectively. Moreover, all 22 patients (100%) with metastatic status were defined accordingly. These data demonstrate that combined analysis of serum Tg with EpCAM+-CECs is suitable to distinguish the patients at disease-free status from the patients with distant metastasis. CEC testing thereby can supplement the current standard methods for monitoring disease status of PTC. Citation Format: Ching-Ping Tseng, Jen-Der Lin, Hung-Chih Lin, Ju-Chien Cheng. Combined analysis of circulating epithelial cell count and serum thyroglobulin for differentiating disease status of the patients with papillary thyroid carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 461.