J. D. Pasternak1, N. Seiser1, J. E. Gosnell1, I. Suh1, Q. Duh1, W. T. Shen1 1University Of California – San Francisco,Endocrine Surgery,San Francisco, CA, USA
Introduction:
Up to 20% of patients with Papillary Thyroid Cancer (PTC) are found to have postoperative nodal metastases in the neck. While reoperative lymphadenectomy remains the most common method for addressing recurrent/persistent disease, new methods which avoid surgical risk are being sought to address small, asymptomatic lesions. Ethanol (ETOH) ablation of metastatic thyroid cancer in the neck has been described as a potential safe and effective alternative to surgery.
Methods:
We report consecutive ultrasound guided ETOH ablation treatments in patients with recurrent, metastatic PTC at a tertiary care Endocrine Surgery Unit over the past 5 years. A retrospective review of prospectively collected data was undertaken. Patient demographics, pathology, imaging and operative history, ETOH injection complications as well as post injection thyroglobulin (Tg) and sonographic trends were studied. Technique of ETOH injection was standardized with ultrasound guidance and the use of 1cc/cm3 of 100% ethanol solution.
Results:
Five treatments of ultrasound guided percutaneous ethanol injection in 4 patients with recurrent metastatic papillary thyroid cancer were studied. All patients had been previously treated with radioactive iodine (Mean: 1.25 treatments of 174mCi), however, in the 3 cases with a pretreatment I-131 scan, there was no uptake of radioiodine in the treated disease. In the 4 cases with pre-treatment FDG-Positron Emission Tomography (PET), all showed the treated lesions to be FDG-avid. Median follow-up time from the most recent treatment was 28.5 months, with no progression of disease in all of the treated lesions. There were no complications, including post treatment pain, hoarseness or dysphagia. Detected serum Tg in patients without Tg-antibody decreased after treatment.
Conclusion:
With the growing body of literature focusing on the indolence of metastatic PTC, surgeons seeking a less invasive approach to deal with smaller asymptomatic nodal metastases in the neck can consider ETOH ablation. The authors' proposed criteria for ETOH ablative treatment includes small lesions that 1) would be difficult to surgically resect, such as deep nodes in a previously irradiated and/or re-operative neck, 2) are sonographically visible and 3) are negative on radioiodine scan and positive on FDG-PET. As demonstrated by a small set of patients in a tertiary care endocrine surgery unit, ETOH ablation is safe and effective at controlling progression of targeted local disease.
