The Risk of Thyroid Cancer in Patients with Thyroid Nodule 3 Cm Or Larger

Pre-operative FNA in goiter with compressive symptoms: a systematic review and meta-analysis

OBJECTIVE

There are currently no firm recommendations regarding the necessity of preoperative FNA in patients with symptomatic goiter. Fine-needle aspiration (FNA) is an efficient and reliable method for determining the risk of malignancy of thyroid nodules, thus, it became the primary procedure for diagnosing neoplasms and guiding surgical treatment. We performed this systematic review of articles to establish the necessity of FNA in patients with compressive goiter.

METHODS

Following PRISMA guidelines, a systematic literature search was conducted using electronic databases. Included were studies dealing with euthyroid goiter and compressive symptoms in adult patients designated to undergo therapeutic surgery. Two reviewers independently extracted the data and assessed the risk of bias using the ROBVIS (visualization tool). Our main outcome measure was final histology compared to preoperative FNA.

RESULTS

The initial search identified 3304 relevant studies. After screening and quality assessment, 14 studies were included in the systematic review. The FNA accuracy of malignant and non-malignant nodules diagnosed correctly preoperatively, was 88.4%. In a meta-analysis which included both benign and malignant preoperative FNA results with subsequent postoperative histology, we observed a relative risk of 0.79.

CONCLUSION

Our data underscores the significant value of preoperative FNA when planning a thyroidectomy for patients with a goiter. The FNA results enable both the physician, and the patient to make informed decisions, consider a staged surgical approach if necessary, determine an appropriate follow-up strategy, and discuss potential complications based on the preoperative findings.

The necessity of fine-needle aspiration biopsy in surgical decision-making for thyroid nodules larger than 3 cm

Ultrasound-guided fine-needle aspiration biopsy (FNAB) is an essential diagnostic tool for detecting malignancy in thyroid nodules. The objective of this study was to evaluate the necessity of FNAB in the treatment decision-making process for thyroid nodules exceeding 3 cm in size. The records of patients who underwent thyroidectomy in our center between 2018 and 2023 were retrospectively reviewed. The study included patients with an index nodule size exceeding 3 cm. Exclusion criteria were missing data, treatment for a different oncological condition, recurrent disease, and purely cystic nodule. Patients were categorized into 2 groups based on the size of the index nodule: Group 1 included nodules measuring between 3 to 4 cm, and Group 2 included nodules 4 cm and larger. Demographic data, FNAB results, and histopathological findings were recorded. The specificity, sensitivity, false negative, and false positive rates of FNAB were calculated. There were 1935 patients who underwent thyroidectomy within the specified date range. In 359 of these patients, the index nodule size was 3 cm or more. There were 188 patients with nodule size between 3 and 4 cm. The mean age was 50.42 ± 13.34 years, and 257 patients were female (F/M ratio = 2.5/1). Fine needle aspiration biopsy was performed on 237 patients, resulting in 65 false negatives. Both the incidence of malignancy and the rate of FNAB false negatives were higher in nodules measuring 4 cm or larger. This study identified a high malignancy rate and a significant rate of false negatives in FNAB of thyroid nodules larger than 3 cm. These findings highlight the importance of carefully considering these factors in the surgical planning of such nodules.

Stratifying High-Risk Thyroid Nodules Using a Novel Deep Learning System

INTRODUCTION

The current ultrasound scan classification system for thyroid nodules is time-consuming, labor-intensive, and subjective. Artificial intelligence (AI) has been shown to increase the accuracy of predicting the malignancy rate of thyroid nodules. This study aims to demonstrate the state-of-the-art Swin Transformer to classify thyroid nodules.

MATERIALS AND METHODS

Ultrasound images were collected prospectively from patients who received fine needle aspiration biopsy for thyroid nodules from January 2016 to June 2021. One hundred thirty-nine patients with malignant thyroid nodules were enrolled, while 235 patients with benign nodules served as controls. Images were fed to Swin-T and ResNeSt50 models to classify the thyroid nodules.

RESULTS

Patients with malignant nodules were younger and more likely male compared to those with benign nodules. The average sensitivity and specificity of Swin-T were 82.46% and 84.29%, respectively. The average sensitivity and specificity of ResNeSt50 were 72.51% and 77.14%, respectively. Receiver operating characteristics analysis revealed that the area under the curve of Swin-T was higher (AUC=0.91) than that of ResNeSt50 (AUC=0.82). The McNemar test evaluating the performance of these models showed that Swin-T had significantly better performance than ResNeSt50.Swin-T classifier can be a useful tool in helping shared decision-making between physicians and patients with thyroid nodules, particularly in those with high-risk characteristics of sonographic patterns.

Do large thyroid nodules (≥4 cm) without suspicious cytology need surgery?

Background

Fine-needle aspiration biopsy (FNAB) is a good diagnostic tool for thyroid nodules; however, its high false-negative rate for giant nodules remains controversial. Many clinicians recommend surgical resection for nodules >4 cm owing to an increased risk of malignancy and an increased false-negative rate. This study aimed to examine the feasibility of this approach and investigate the incidence of malignancy in thyroid nodules >4 cm without suspicious cytology based on medical records in our center.

Methods

This was a retrospective analysis of 453 patients that underwent preoperative FNAB for nodules measuring >4 cm between January 2017 and August 2022 at Severance Hospital, Seoul.

Results

Among the 453 patients, 140 nodules were benign and 119 were indeterminate. Among 259 patients, the final pathology results were divided into benign (149) and cancerous (110) groups, and the prevalence of malignancy was 38.9% in the benign group and 55.5% in the indeterminate group. Among the malignancies, follicular carcinoma and follicular variants of papillary carcinoma were observed in 83% of the cytologically benign group and 62.8% of the indeterminate group.

Conclusion

Preoperative FNAB had high false-negative rates and low diagnostic accuracy in patients with thyroid nodules >4 cm without suspicious cytologic features; therefore, diagnostic surgery may be considered a treatment option.

Suspicious thyroid nodules ≥4 cm require diagnostic lobectomy regardless of their benign fine needle aspiration results

BACKGROUND/OBJECTIVE

The diagnostic accuracy of fine needle aspiration biopsy (FNAB) seems limited in large thyroid nodules with Bethesda Cat. 2 result. We aimed to determine the incidence of carcinoma with benign cytology and the reason for the high false-positive rate in thyroid nodules ≥4 cm.

METHODS

The records of 103 patients with thyroid nodules ≥4 cm with preoperative cytological diagnosis of Bethesda Cat. 2 who underwent thyroidectomy were consecutively reviewed. Characteristics between patients with malignant vs. benign pathology were compared.

RESULTS

Forty patients (38.8%) had malignancy. Malignancy was subclassified into follicular variant of papillary thyroid carcinoma (43%), minimally invasive follicular thyroid carcinoma (20.0%), and minimally invasive Hurthle cell thyroid carcinoma (10.9%). Patients with malignant cytology had significantly more suspicious ultrasound findings than those with benign cytology (p = 0.001).

CONCLUSIONS

Preoperative FNAB showed high false-negative rates in patients with thyroid nodules ≥4 cm with benign cytology. These nodules have a high malignancy rate with suspicious ultrasound findings.