[Cyto-inactivation instantly induced by microwave ablation on thyroid nodules]

Objective: To explore the effect of microwave ablation on thyroid nodules cell activity by the reaction of key enzyme of cell activation. Methods: From November 2017 to February 2018, 104 patients with 120 thyroid nodules underwent ultrasound-guided microwave ablation at Super-minimally Invasive Medicals, Shanghai International Medical Center, aged 14-55 years, 42 males and 62 females.Twice core needle biopsy were performed before and after thermal ablation.The specimen were using hematoxylin and eosin (HE) staining and enzyme histochemical staining with include succinate dehydrogenase (SDH) and nicotinamide adeninedinucleotide phosphate diaphorase (NADPH-d), respectively, and observe under microscope. Results: Enzyme histochemical staining showed that the positive rate of SDH and NADPH-d in the marginal region and transitional region were 100% before ablation, and were 0% immediately after ablation.The positive rate of SDH and NADPH-d histochemical staining in the same area before and immediately after ablation was statistically significant (P<0.05). Shortly after microwave ablation, the tissue structure and cell morphology showed no obvious alteration in HE stained sections, but in sections with enzyme histochemical staining, the activity of SDH and NADPH-d in ablated tissue disappeared.The accuracy rate of pathologic diagnosis was 100% after ablation. Conclusions: SDH and NADPH-d enzyme activity may be better in evaluating the short-term efficacy of microwave ablation of thyroid nodules than HE staining.