An unsuspicious thyroid nodule with fatal outcome

Area of Science:

• Oncology
• Radiology
• Pathology

Background:

• Thyroid nodule evaluation systems aim to stratify malignancy risk based on common histotypes.
• Existing ultrasonography (US) classification systems may not adequately identify rare thyroid neoplasms.

Observation:

• A 77-year-old woman presented with metastatic disease and a solitary thyroid nodule.
• The thyroid nodule exhibited benign ultrasonographic features, classified as low risk by six systems.
• Despite low-risk US findings, fine-needle aspiration cytology revealed anaplastic cancer.

Findings:

• Histological examination confirmed follicular thyroid carcinoma with anaplastic dedifferentiation.
• The patient's condition rapidly progressed, leading to death shortly after diagnosis.

Implications:

• Accurate US characterization of rare thyroid neoplasms is crucial for early diagnosis.
• Timely diagnosis of aggressive thyroid cancers significantly impacts patient prognosis.
• Rethinking current US-based risk stratification for uncommon thyroid cancer variants is warranted.