PANCE Endocrinology Practice Test

Ultrasound risk features guide whether a thyroid nodule should be biopsied. The finding that most often leads to fine-needle aspiration is the presence of suspicious characteristics, specifically irregular margins and microcalcifications, which meaningfully increase the likelihood of malignancy—most classically papillary thyroid carcinoma. These features push clinicians to obtain cytology to confirm or exclude cancer, even if the nodule isn’t very large. By contrast, a simple cyst with anechoic fluid is usually benign and monitored or aspirated for relief rather than biopsied for cancer; a homogeneous iso-echoic solid nodule with smooth margins tends to be low risk and may be managed with observation or biopsy only if larger or accompanied by other risk features; a comet-tail artifact is typically seen in benign colloid nodules and does not prompt biopsy.