Core-needle biopsy in thyroid nodules: performance, accuracy, and complications.

Area of Science:

• Endocrinology
• Surgical Pathology
• Radiology

Background:

• Thyroid nodules are common, and accurate diagnosis is crucial for appropriate management.
• Fine-needle aspiration cytology (FNAC) is the standard diagnostic tool, but can have limitations.
• Core-needle biopsy (CNB) offers an alternative diagnostic modality for thyroid nodules.

Purpose of the Study:

• To evaluate the diagnostic performance and safety of ultrasound-guided core-needle biopsy (CNB) as a first-choice method for thyroid nodules.
• To assess the accuracy, complication rates, and utility of repeat biopsies in a large patient cohort.

Main Methods:

• Retrospective review of 4412 ultrasound-guided CNBs performed on 4112 thyroid nodules in 3768 patients over 11 years.
• Classification of CNB results into insufficient, benign, follicular lesion (indeterminate), and malignant categories.
• Final diagnosis determined by surgical pathology or at least 2-year follow-up for non-operated patients.

Main Results:

• The study included 4412 CNBs, with diagnostic rates of 96.6%. Insufficient diagnoses occurred in 3.4%, benign in 84%, follicular lesions in 6.3%, and malignant in 6.3%.
• Sensitivity was 96% and specificity 93.7% when considering follicular lesions and malignancy as positive outcomes. The positive predictive value for malignancy was 98.6%.
• Complication rates were low, with minor complications in 2.2% and major complications in 0.09% of procedures. Repeat biopsies improved diagnostic yield for initially insufficient samples.

Conclusions:

• Ultrasound-guided core-needle biopsy (CNB) is an accurate and safe diagnostic tool for thyroid nodules, with a low rate of non-diagnostic and indeterminate results.
• CNB demonstrates high reliability, particularly for benign diagnoses, and can serve as an effective alternative to FNAC when FNAC performance is suboptimal.
• Repeat core-needle biopsies are beneficial for improving diagnostic yield in cases of initially non-diagnostic results, and the overall complication rate is low.