Management of cystic or predominantly cystic thyroid nodules: role of simple aspiration of internal fluid

Thyroid Nodules: Past, Present & Future

The ability to distinguish benign from malignant thyroid nodules has been a challenge for over a century. Historically, thyroidectomy, as the only definitive method to diagnose thyroid cancer, led to a significant number of thyroid resections for benign disease considering that approximately 90-95% of thyroid nodules are benign. Diagnostic advancements including highly sensitive ultrasonography, fine needle aspiration cytology, molecular studies and future use of artificial intelligence, help distinguish benign from malignant and has significantly reduced the number of unnecessary surgeries for benign nodules. Current and likely future diagnostic improvements have led us to a new conundrum. While decreasing the number of surgeries for benign disease, we are now overdiagnosing and overtreating low-risk subclinical malignancies. Here we describe some of the changes leading to our current state.

Comparison of the effectiveness of lauromacrogol injection for ablation and microwave ablation in the treatment of predominantly cystic thyroid nodules: a multicentre study

PURPOSE

To compare the therapeutic efficacy and safety of microwave ablation (MWA) and lauromacrogol injection for ablation (LIA) for benign predominantly cystic thyroid nodules.

MATERIALS AND METHODS

In this retrospective study, 85 patients with predominantly cystic thyroid nodules (PCTNs) who underwent microwave ablation (MWA) or lauromacrogol injection for ablation (LIA) between June 2019 and August 2022 at three hospitals were included in our research. Forty-six patients were treated with microwave ablation, and thirty-nine patients were treated with lauromacrogol injection for ablation. The baseline characteristics, nodal volume, volume reduction rate (VRR), and incidence of postoperative complications were compared between these two groups.

RESULTS

After treatment, there were significant differences in the thyroid nodule volume and the volume reduction rate (VRR) at different follow-up times between the groups (p < 0.001). There were no significant differences in the nodal volume or the volume reduction rate (VRR) between the MWA group and the LIA group at 1, 3, 6, and 12 months (p > 0.05). Of note, no serious intraoperative or postoperative complications occurred in the corresponding group.

CONCLUSION

MWA and LIA are very effective and safe strategies for the treatment of predominantly cystic thyroid nodules. However, LIA is more advantageous in that it is less expensive and has a shorter length of hospital stay than MWA.

Efficacy of Ethanol Ablation for Benign Thyroid Cysts and Predominantly Cystic Nodules: A Systematic Review and Meta-Analysis

BACKGROUND

Ultrasound-guided minimally invasive procedures are widely used to treat thyroid diseases. The objective of this study was to assess the efficacy and safety of ethanol ablation (EA) in comparison with other non-surgical options in the treatment of benign thyroid cystic nodules.

METHODS

We conducted a systematic search of studies on EA for thyroid cystic nodules, mainly in the Ovid-MEDLINE and Embase, Web of Science, and Cochrane databases. The standardized mean difference (SMD) of the volume reduction ratio (VRR) after EA versus other non-surgical treatments comprised the primary outcome, whereas the odds ratio (OR) of therapeutic success rates between the two groups comprised the secondary outcome.

RESULTS

The meta-analysis included 19 studies (four randomized controlled trials and 15 non-randomized studies) with 1,514 participants. The cumulative VRR of EA was 83.908% (95% confidence interval [CI], 79.358% to 88.457%). EA had a significantly higher pooled VRR (SMD, 0.381; 95% CI, 0.028 to 0.734; P=0.030), but not a significantly higher pooled therapeutic success rate (OR, 0.867; 95% CI, 0.132 to 5.689; P=0.880), than other forms of non-surgical management including radiofrequency ablation (RFA), polidocanol sclerotherapy, and simple aspiration with or without saline flush. However, the VRR and therapeutic success rate were not significantly different between EA and RFA. Major complications were recorded only in six patients (0.53%) with self-limiting dysphonia.

CONCLUSION

The role of EA as the first-line treatment for benign thyroid cysts and predominantly cystic nodules is supported by its high effectiveness and good safety profile compared to other currently available non-surgical options.

Factors influencing the outcome from ultrasonography-guided fine-needle aspiration of benign thyroid cysts and partially cystic thyroid nodules: A multicenter study

PURPOSE

The effect of ultrasonography (US)-guided fine-needle aspiration (US-FNA) for the collapse of benign cystic thyroid nodules is still unclear. This study aimed to assess the positive response rate following US-FNA of the cystic component of thyroid cysts and of partially cystic thyroid nodules (PCTNs), and to evaluate the factors influencing the outcome.

METHODS

From June to December 2013, seven radiologists at seven institutions prospectively performed US-FNA on 320 cystic thyroid nodules in 320 patients. Among them, 179 underwent at least one follow-up US examination following US-FNA of the cystic component at each institution by the same radiologist. A variety of factors, including US features of cystic thyroid nodules, the characteristics of the aspirates, and the follow-up US findings, were analyzed.

RESULTS

Of 179 cystic thyroid nodules, there were 53 thyroid cysts and 126 PCTNs. Of 179 cystic thyroid nodules, no malignancies were detected. On follow-up US, the mean size reduction rate of the cystic component was 31.9%, and 102 out of 179 thyroid nodules (57.0%) were assigned to the response group. On univariate analysis, the degree of aspiration and time interval between US-FNA and the final follow-up US showed the significant differences between the response and no response groups. On multivariate analysis, the only factor that influenced the outcome was the nodule type. The cystic component's positive response rate after simple aspiration was higher in the thyroid cysts than in the PCTNs.

CONCLUSIONS

US-FNA may be effective at collapsing the cystic components of benign thyroid cysts and PCTNs.

Statement and Recommendations on Interventional Ultrasound as a Thyroid Diagnostic and Treatment Procedure

The recently published guidelines of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) on interventional ultrasound (INVUS)-guided procedures summarize the intended interdisciplinary and multiprofessional approach. Herewith, we report on recommendations for interventional procedures for diagnosis and treatment of the thyroid gland.

Thyroid Imaging Reporting and Data System and Ultrasound Elastography: Diagnostic Accuracy as a Tool in Recommending Repeat Fine-Needle Aspiration for Solid Thyroid Nodules with Non-Diagnostic Fine-Needle Aspiration Cytology

The Thyroid Imaging Reporting and Data System (TIRADS) has been found to be accurate in the stratification of malignancy risk, and elastography has been found to have a high negative predictive value in non-diagnostic thyroid nodules. Through assessment of 104 solid non-diagnostic thyroid nodules, this study investigated the role of both in recommending repeat ultrasonography-guided fine-needle aspiration for solid thyroid nodules with non-diagnostic cytology. All nodules were classified by TIRADS (categories 4a, 4b, 4c and 5), and elastography scores were assigned according to the Rago and Asteria criteria. The malignancy risks for TIRADS categories 4a, 4b, 4c and 5 were 12.5%, 25.0%, 25.8% and 16.7%, respectively. Elastography revealed the highest diagnostic performance for TIRADS category 4a, with a sensitivity, specificity, negative predictive value, positive predictive value and accuracy of 100%, 85.7%, 100%, 50% and 87.5% for the Asteria criteria. Observation may be considered for non-diagnostic solid nodules that have no other suspicious ultrasonographic features and are also benign on real-time strain elastography using the Asteria criteria.