This study aimed to investigate the value of dynamic changes of
midkine (MK) to monitor post-surgical patients with
papillary thyroid cancer (PTC) who were managed with I
therapies.MK concentration at initial I ablation
therapy (MK1) as well as 10 to 12 months thereafter (MK2) was evaluated. And the dynamic changes of
thyroglobulin (Tg) were compared (Tg1 and Tg2). Patients with MK influencing co-morbidities and with positive
thyroglobulin antibodies were excluded. Concentrations of MK were measured by
enzyme-linked
immunosorbent assay.There were 241 PTC patients (36 males, 205 females) enrolled, 55 cases had
metastases (8 males, 47 females) during their follow-up. Cox regression showed if Tg2 decreased (compared with Tg1), but not to less than 1.0ng/mL under TSH stimulation, the risk of
metastases was 12.554 times more than if it could decrease to the optimal level. If Tg2 increased, the risk is 19.461 times higher. As for MK, if MK2 level decreased (compared with MK1), but not to a normal level, the risk of
metastases is 3.006. If MK2 level increased, it would be 5.030 likely to had
metastases.Our results indicated that MK could potentially be used as a disease monitoring
biomarker for PTC, although inferior to Tg.