Parathyroid Adenoma Orientation for Gland Embryologic Origin on Ultrasonography.

Importance: Accurate preoperative localization is critical to success in targeted parathyroidectomy for primary hyperparathyroidism. Objective: To determine if the association between the long axis of a parathyroid adenoma (PTA) candidate and strap musculature on sagittal ultrasonography (US) can be used to predict the embryologic origin of the gland. Design, Setting, and Participants: This diagnostic study was performed using the Stanford Research Repository. Patients 18 years or older with primary hyperparathyroidism who underwent parathyroidectomy between January 2009 and October 2021 were considered. Additional inclusion criteria were having clear sagittal view of the adenoma candidate on US, confirmation of the gland of origin intraoperatively, and confirmation of hypercellular parathyroid on final pathology. Data were analyzed from October 2021 to June 2022. Exposures: B-mode US and surgical parathyroidectomy. Main Outcomes and Measures: The index test was using US to measure the angle between the long axis of an adenoma candidate and the strap musculature in the sagittal plane. This angle was used to test whether inferior and superior PTAs could be accurately assigned. The hypothesis was formulated prior to data collection. Results: A total of 426 patients (mean [range] age, 61.1 [20-96] years; 316 [74.2%] female) with 442 adenomas met inclusion criteria. Of the 442 adenomas, 314 (71.0%) had measurable angles, of which 204 (46.2%) were assigned a superior origin, 238 (53.8%) were assigned an inferior origin, and 128 (29%) were indeterminate. Of the surgically identified superior PTAs, 144 (70.6%) had a definable angle, and of the surgically identified inferior PTAs, 170 (71.4%) had a definable angle. The receiver operating characteristic analysis found 94° as the optimized angle for differentiating true negatives from true positives, with an overall sensitivity of 74% and specificity of 72%. This supported using 90° as a break point for US review. True positives were considered superior adenomas with an angle greater than 90°; true negatives were inferior adenomas with an angle less than 90°. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of angulation analysis for determining PTA origin were 72.2% (95% CI, 64.9%-79.5%), 73.5% (95% CI, 66.9%-80.1%), 69.8% (95% CI, 62.5%-77.1%), 75.8% (95% CI, 69.3%-82.3%), and 72.9%, respectively. A subgroup analysis of 426 adenomas using the posterior carotid artery border on transverse US as a surrogate for predicting gland origin showed the following for sensitivity, specificity, positive predictive value, negative predictive value, and accuracy: 49.5% (95% CI, 42.6%-56.4%), 82.3% (95% CI, 77.3%-87.3%), 71.4% (95% CI, 63.9%-78.9%), 64.6% (95% CI, 59.1%-70.1%), and 66.9%, respectively. Conclusions and Relevance: This diagnostic study showed that PTA angulation on sagittal plane US can be used to predict gland of origin and guide surgery. The relationship between adenoma and posterior carotid artery border on transverse US can also be used to predict gland origin. These easy-to-apply US-based tests can be used in conjunction with other imaging modalities to guide targeted parathyroidectomy.

Impact of the COVID-19 Pandemic on Thyroid Cancer Surgery.

The COVID-19 pandemic caused major disruptions to healthcare services in 2020, delaying cancer diagnosis and treatment. While early-stage thyroid cancer often progresses slowly, it is crucial to determine whether treatment delays associated with the pandemic have impacted the clinical presentation and management of advanced-stage thyroid cancer. The purpose of our study was to determine the impact of the early COVID-19 pandemic on thyroid cancer presentation and treatment times. Utilizing the National Cancer Database, chi-squared tests and regression analyses were performed to compare patient demographic and clinical characteristics over time for 56,011 patients diagnosed with primary thyroid cancer who were treated at the Commission on Cancer-accredited sites in 2019 and 2020. We found that thyroid cancer diagnoses decreased between 2019 and 2020, with the biggest drop among patients with cT1 disease relative to other T stages. We also found that patients diagnosed with thyroid cancer in 2020 had similar treatment times to patients diagnosed in 2019, as measured by both the time between diagnosis and start of treatment and the time between surgery and start of radioactive iodine therapy. Overall, our study suggests that resources during the pandemic were allocated to patients with advanced thyroid disease, despite a decrease in diagnoses.

Thyroid Nodule Rupture Following Radiofrequency Ablation for Benign Thyroid Nodules.

Importance: Nodule rupture is a rare but serious complication of thyroid radiofrequency ablation (RFA). With growing adoption of thyroid RFA across the US, an understanding of thyroid nodule rupture (TNR) is crucial for recognition, management, and, ultimately, prevention. Objective: To determine procedural and patient factors that may contribute to TNR and describe experiences in managing TNR while synthesizing existing literature. Design, Setting, and Participants: This retrospective case series examined all RFA procedures for benign thyroid nodules performed by 2 attending physicians at a single academic referral center between December 2019 and January 2024. A total of 298 consecutive patients underwent RFA for benign thyroid nodules. Criteria for offering RFA included nodules with 2 benign fine-needle aspirations, no suspicious ultrasonography features, a greatest dimension of 2 cm or greater, compressive or cosmetic concerns, and accessibility to a straight needle. Exposures: All RFAs were performed using ultrasonography guidance using the moving-shot technique and a 7-mm or 10-mm active tip. Main Outcomes and Measures: The primary outcome was TNR, and measures were procedure, nodule, and patient characteristics that may have contributed to its pathogenesis. Secondary outcomes were nodule volume reduction, thyroid function, and management and sequelae of TNR. The hypothesis on the pathogenesis of TNR was formed before data collection. Results: Six of 298 patients (2%; 4 women [67%]) with a mean age of 48.5 years (range, 34-65 years) experienced TNR for a mean of 36 days postprocedure (range, 19-54 days). The mean (SD) initial nodule volume among patients with TNR was 31.45 (16.52) mL, and 3 of 6 patients (50%) underwent prior lobectomy. All ruptures were anterior. All patients were treated conservatively, and none required surgery. Five patients recovered completely; the sixth and most recent patient was healing as of last follow-up. Conclusions and Relevance: There are limited data on the etiology and optimal management of TNR. These 6 cases of anterior rupture suggest that a potential contributor to TNR is thermal and mechanical trauma exerted at the fulcrum point during the moving-shot technique. The use of a smaller active tip (eg, 7 mm) and cessation of energy delivery before this point may help avoid TNR. More robust reporting of this complication may clarify risk factors for and enhance prevention of TNR.

Radiofrequency ablation of benign thyroid nodules: A prospective, multi-institutional North American experience.

BACKGROUND: Radiofrequency ablation for benign thyroid nodules aims to achieve a volume reduction rate of ≥50%. However, factors that predict treatment success have not been defined in a large-scale study. METHODS: A prospective cohort study of biopsy-proven benign thyroid nodules treated with radiofrequency ablation at 3 institutions was performed. Patient demographics, nodule sonographic features, procedural data, and nodule volume reduction were evaluated. Binary logistic regression analysis was performed to identify features associated with treatment response. RESULTS: A total of 620 nodules were analyzed. The pooled median volume reduction rate at 12 months was 70.9% (interquartile range 52.9-86.6). At 1 year follow-up, 78.4% of nodules reached treatment success with a volume reduction rate ≥50%. The overall complication rate was 3.2% and included temporary voice changes (n = 14), vasovagal episodes (n = 5), nodule rupture (n = 3), and lightheadedness (n = 2). No permanent voice changes occurred. Four patients developed postprocedural hypothyroidism. Large baseline nodule volume (>20 mL) was associated with a lower rate of successful volume reduction (odds ratio 0.60 [0.37-0.976]). Large nodules achieved treatment success by 12-month follow-up at a rate of 64.5%, compared with 81.4% for small nodules and 87.2% for medium nodules. CONCLUSION: To our knowledge, this is the largest North American cohort of patients with benign thyroid nodules treated with radiofrequency ablation. Overall, radiofrequency ablation was an effective treatment option with a low risk of procedural complications. Large volume nodules (>20 mL) may be associated with a lower rate of successful reduction with radiofrequency ablation treatment.