Percutaneous Ethanol Injection for Primary Papillary Thyroid Microcarcinoma

We hypothesize that percutaneous ethanol ablation (PEA) for primary papillary thyroid
microcarcinoma (PTMC) has equivalent oncologic outcomes to current treatment options
including observation, thyroid lobectomy and total thyroidectomy. In addition, we
hypothesize that it will yield superior long-term quality of life, including measures of
pain, voice, and cosmesis than standard surgical therapy (total thyroidectomy). If our
hypotheses are correct, the findings of this study have the potential to fundamentally
change clinical management of this group of patients.

This study was changed from its initial design: a 2 arm study comparing PEA to surgery
(Amended April 30, 2015). The change in design was made based on several discussions within
Yale Endocrine Surgery, with patients diagnosed with PTMC, and knowledge of other
institutions performing PEA for PTMC as standard of care.

The study team had been contacted by numerous potential subjects interested in PEA who were
unwilling to be randomized to surgery. Because patients interested in PEA appeared to be
firmly against the idea of thyroidectomy, we believed that we would be unable to enroll
sufficient patients to this study as the protocol originally stood.

Inclusion Criteria:

- Age 18 years and older

- Diagnosis: single, cytology-proven papillary thyroid carcinoma measuring 1 cm or less
in diameter (microcarcinoma, T1a), without visible extrathyroidal extension, and with
negative central and lateral neck lymph nodes by ultrasound

Exclusion Criteria:

- Patient refusal to participate

- History of prior thyroid or parathyroid surgery

- Previous recurrent laryngeal nerve injury

- Inability to make decisions or comply with follow up

- Co-existing indication for thyroidectomy

- Aggressive cytological or molecular features

- Multifocal papillary thyroid carcinoma

- Pregnant or breast-feeding

- Anatomically unfavorable location of the tumor (proximity to recurrent laryngeal
nerve or trachea)

- Documented or suspected distant metastasis

- History of radiation to neck or face

- Family history of thyroid cancer