Ultrasound Elastography Predicts Thyroid Nodule Volume Reduction Rate After Percutaneous Ethanol Ablation

OBJECTIVES

To evaluate the safety and efficacy of percutaneous ethanol ablation (PEA) on indeterminate thyroid nodules (Bethesda III and IV) based on ultrasound (US) elastography by assessing the volume reduction rate (VRR), relative reduction in size, resolution of compressive symptoms, and post-procedural complications.

MATERIALS AND METHODS

This is a retrospective cohort study of all thyroid nodules treated with PEA by a single surgeon at a North American tertiary referral center. Study variables included demographics, nodule characteristics, Bethesda classification, US elastography, presence of compressive symptoms, thyroid function, and post-procedural complications. Relative volume reductions and VRR were calculated at 3- and 6-month follow-ups.

RESULTS

Thirty-four thyroid nodules were evaluated in 22 patients. All thyroid nodules underwent a fine needle aspiration prior to PEA. After 6 months, 45% of all thyroid nodules exhibited a VRR of ≥50%. A significant VRR was achieved in the soft thyroid nodules at 6 months (42.15% ± 31), compared to the stiff nodules with 30.92% ± 91.53, P < .05. Post-PEA thyroid stimulating hormone levels did not significantly change after the procedure. Compressive symptoms resolved in all 5 patients who reported it. One patient developed transient vocal cord paresis that resolved in 3 months.

DISCUSSION

To the best of our knowledge, this is the largest series of PEA for thyroid nodules in North America. Ultrasound elastography is a useful adjunct in predicting the success of PEA for nonmalignant thyroid nodules. Percutaneous ethanol ablation is both a safe and effective alternative to surgery for relief of compressive symptoms in select patients.

Percutaneous ethanol ablation in managing predominantly cystic thyroid nodules: An eastern India perspective

AIMS

Percutaneous aspiration and ethanol injection (PEI) is effective in managing predominantly cystic (>50% cystic) thyroid nodules with efficacy ranging from 38-85%. We aimed to evaluate efficacy, safety, and factors determining outcomes of PEI in managing simple cystic (purely cystic) vs. complex cystic (having both cystic and solid components) thyroid nodules.

MATERIALS AND METHODS

Predominantly cystic thyroid nodules, without any ultrasonography and/or fine needle aspiration, evidence of malignancy were aspirated ultrasonography guided. Sterile 100% ethanol (50-100% volume aspirated) was injected and reviewed monthly for 3 months and thereafter 3 monthly. Responders were defined as ≥ 50% reduction in nodule volume.

RESULTS

Sixty-five patients out of 152 considered underwent PEI. Sixty patients [simple cystic (42) and complex cystic (18)] with mean follow-up of 12.3 ± 2.88 months were analyzed. Response rate of PEI was 78.33% [simple cystic (92.86%) and complex cystic (44.44%) nodules; P < 0.001]. Also, 31.67% patients achieved remission at 1(st) month. And, 46.67% patients achieved remission between 1-6-months follow-up. Kaplan Meier analysis showed significantly improved outcomes in patients with simple cystic nodules (P < 0.001). Cox-regression revealed type of nodule (simple cystic vs. complex cystic) to be predictive of outcome (P = 0.034). Complex cystic nodules were 67.6% less likely to go into remission, compared to simple cystic nodules. Baseline nodule size, aspirate, or volume of ethanol injected did not predict outcome.

CONCLUSIONS

PEI is safe and should be treatment of choice for simple cystic thyroid nodules. PEI for complex cystic thyroid nodules are associated with lower response, increased recurrence, and need for repeated PEI.