ABSTRACT
BACKGROUND: Treatment for neck lymph node metastases after adequate initial surgery in medullary thyroid carcinoma (MTC) has been controversial. Ultrasound (US)-guided radiofrequency ablation (RFA) has been widely used in recurrent well-differentiated thyroid carcinoma. Here, we report for the first time the use of RFA in a patient with recurrent MTC. CASE SUMMARY: We report the case of a 56-year-old woman with cervical lymph node metastases of MTC. Four years previously, she had undergone a total thyroidectomy and neck lymph node dissection. A neck US revealed many enlarged nodes during the follow-up period. Moreover, the serum calcitonin jumped to 198.17 pg/mL, which strongly indicated the recurrence of MTC. Subsequently, two metastatic lymph nodes were confirmed by US-guided fine-needle aspiration-cytology and fine-needle aspiration-calcitonin, and then the patient was treated with RFA. Four months later, the neck US and a contrast-enhanced US showed obvious shrinkage in the ablation zones, and the serum calcitonin dropped to 11.80 pg/mL. CONCLUSION: This case suggests that RFA may be an effective and safe treatment for local recurrent MTC.
ABSTRACT
DNA methylation at the 5 position of cytosine (5-mC) is an epigenetic hallmark that is critical in various biological and pathological processes such as DNA methylation regulation, and initiation and development of cancers. 5-mC can be oxidized to 5-hydroxymethylcytosine (5-hmC) by the ten-eleven translocation family of DNA hydroxylases. Accumulating evidence has reported that loss of 5-hmC is associated with cancer development. However, its level in papillary thyroid carcinoma (PTC) remains unclear. The present study reports that the loss of 5-hmC is an epigenetic mark of PTCs, associated with their malignant biological behavior, providing diagnostic and predictive advantages over DNA hypomethylation (5-mC), an acknowledged epigenetic alteration in cancer. In addition, the 5-hmC staining levels were decreased in cases of micro-carcinoma with lymph node metastasis, which suggests that 5-hmC expression levels could be used as valuable biomarkers for predicting malignant potential and assist in the selection of therapeutic strategies in PTC; therefore, 5-hmC has the potential to provide a more precise direction for PTC therapy.
