Thyroid Examination: Nodules

A nodule, which might also be called a lump, is an irregular growth of thyroid cells. Some nodules are malignant, but most are benign.

Thyroid cancer has been known as a type of cancer that is latent, that is, having no symptoms or health effects over a lifetime. Thus, detecting all cancers and forcing patients to receive treatment may be sometimes rather disadvantageous, so a detailed examination, such as cytological diagnosis, is not generally conducted for small nodules. In the Thyroid Examination conducted through the Fukushima Health Management Survey, the Confirmatory Examination is not generally performed for nodules of 5 mm or smaller; instead, follow-ups are to be made at the time of the next regularly scheduled ultrasound examination (Primary Examination).

In some cases, a person once diagnosed as Grade A1 is diagnosed as Grade A2 or Grade B in the next examination, or conversely, a person once diagnosed as Grade A2 is subsequently diagnosed as Grade A1.

• Included in this reference material on March 31, 2013
• Updated on March 31, 2017