Thyroglobulin mRNA ectopic expression was an excellent marker to detect lymph node metastasis for patients with papillary thyroid cancer

Abstract

Objective

To investigate whether the mRNA expression of thyroglobulin (TG) and TSH receptor (TSHR) in lymph node could be used to diagnose lymph node metastasis in patients with papillary thyroid cancer (PTC).

Subjects and methods

Around 156 paraffin samples of lymph nodes from 89 patients with PTC after surgery were collected, and the expressions of TG and TSHR mRNA were detected by nested qPCR.

Results

Compared with the results of confirmed histopathology, 86 out of 87 tissues of lymph nodes metastasis ectopically expressed TG mRNA, while 66 out of 69 tissues of non-metastasis lymph nodes did not express the TG mRNA. The specificity and sensitivity of TG mRNA measurement for detecting the lymph node metastasis were 95.65% and 98.85%, as effective as the first postoperative histopathology. However, the specificity and sensitivity of TSHR mRNA measurement were 92.75% and 85.06%, respectively. The accuracy of TG, TSHR mRNA measurement and the first postoperative histopathology were 97.44%, 88.46% and 95.51%, with the positive predictive rate (PPR) 96.63%, 93.67%, and 98.78%, respectively, negative predictive rate (NPR) 98.51%, 83.12% and 91.89%, respectively, as well as Youden's index 0.95, 0.78 and 0.92.

Conclusions

TG mRNA ectopic expression in the lymph node might be an excellent marker to diagnose the lymph node metastasis for patients with PTCs.