Accuracy and pitfalls of frozen section during thyroid surgery

Area of Science:

• Pathology
• Surgical Oncology

Background:

• Frozen section (FS) is a rapid diagnostic technique used intraoperatively.
• Accurate intraoperative diagnosis is crucial for guiding surgical management of thyroid lesions.

Purpose of the Study:

• To evaluate the diagnostic accuracy of frozen sections in thyroid pathology.
• To identify potential pitfalls and limitations of frozen section analysis in this context.

Main Methods:

• Retrospective review of 190 thyroid pathology cases undergoing frozen section examination.
• Comparison of frozen section diagnoses with final histopathological diagnoses from permanent sections.

Main Results:

• Overall accuracy of frozen section was 95%.
• No false positives were reported; false negatives were primarily associated with follicular adenomas.
• Significant discrepancies included differentiating follicular adenoma from follicular carcinoma (8 cases), and identifying specific malignant cell types.

Conclusions:

• Frozen section is a valuable tool for thyroid surgery, but limitations exist, particularly in distinguishing benign follicular adenomas from malignant follicular carcinomas.
• Careful interpretation and correlation with permanent sections are essential for accurate diagnosis and patient management.
• Deferred diagnoses for definitive permanent section analysis are sometimes necessary, especially for suspected anaplastic or medullary thyroid cancers.