Are all types of thyroid nodules/lumps cancerous?

Thyroid nodules: No, most thyroid nodules are not cancerous. A thyroid ultrasound is very sensitive at picking up tiny and often insignificant nodules. There are some features of thyroid nodules that make them more suspicious, such as large solitary "cold" ones, and other features. The best person to evaluate is an Endocrinologist who does his/her own U/S guided biopsies.

No: The presence of multiple nodules in the thyroid gland are suggestive of a nodular goiter. A solitary lesion in the thryroid gland becomes suspicious of pathology. Here a scan should be performed to see if the lesion is cold or non functioning. If so, surgery recommended since this "adenoma" has a 30% or better chance of being or converting to cancer.

No: The majority of lumps in the thyroid when noted to be multiple on scan represent the condition "multinodular goiter" These are almost always benign. When a solitary lesion is present that is "cold" on isotope scan, this is suspicious for possible malignancy and should always be removed. Bx has a certain degree of error especially if a follicular lesion looking benign has invaded capsule.