Inclusion Criteria:
* Participant must provide voluntary, written informed consent to participate in this clinical investigation.
* Participant agrees to comply with all study procedures, including all follow-up visits.
* Participant with a Bethesda VI cytology (tumor size \<= 1.5 cm, no known regional/distant metastases)
* Participant with a Bethesda V cytology and normal calcitonin levels.
* Ultrasonographic evaluation of tumor to be ablated must show size of less than or equal to 1.5 cm and no extrathyroidal extension or locoregional metastases.
* Participant must have normal complete blood count, blood coagulation profile, and thyroid function test.
* For females of childbearing potential, a negative serum or urine pregnancy test must be obtained at baseline, prior to the procedure.
* Women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. (Refer to Pregnancy Assessment Policy MD Anderson Institutional Policy # CLN1114). This includes all female patients, between the onset of menses (as early as 8 years of age) and 55 years unless the patient presents with an applicable exclusionary factor which may be one of the following: ). This includes all female patients, between the onset of menses (as early as 8 years of age) and 55 years unless the patient presents with an applicable exclusionary factor which may be one of the following:
* Postmenopausal (no menses in greater than or equal to 12 consecutive months).
* History of hysterectomy or bilateral salpingo-oophorectomy.
* Ovarian failure (Follicle Stimulating Hormone and Estradiol in menopausal range, who have received Whole Pelvic Radiation Therapy).
* History of bilateral tubal ligation or another surgical sterilization procedure.
* Approved methods of birth control are as follows: Hormonal contraception (i.e. birth control pills, injection, implant, transdermal patch, vaginal ring), Intrauterine device (IUD), Tubal Ligation or hysterectomy, Subject/Partner post vasectomy, Implantable or injectable contraceptives, and condoms plus spermicide. Not engaging in sexual activity for the total duration of the trial and the drug washout period is an acceptable practice; however periodic abstinence, the rhythm method, and the withdrawal method are not acceptable methods of birth control. Should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately.
* Men treated or enrolled on this protocol must also agree to use adequate contraception prior to the study, for the duration of study participation, and 4 months after completion of study procedure.
Exclusion Criteria:
* FNA findings suggestive of high-grade malignancy
* Presence of regional or distant lymph node metastases.
* Participant had a history of previous neck irradiation.
* Females who are pregnant at time of enrollment.
* Participant has any condition or situation, in the opinion of the site Investigator, that puts the subject at significant risk, could confound the study results, or may interfere significantly with subject's participation in the study.
