It is important to remember that most (more than 90% – 95%) of thyroid nodules are benign and even when a thyroid cancer is diagnosed the outcomes are very often excellent.
Most thyroid cancers at diagnosis are not causing any symptoms but are found incidentally either during a neck or thyroid scan or during a medical examination when a lump might be felt on examination. Symptoms will most commonly occur only when a nodule grows sufficiently to become noticeable and cause pressure (which can also occur with benign nodules), when surrounding structures are involved or if lymph glands in the neck become enlarged.
A person who notices a new or fast growing (most often painless) lump in the neck should always seek medical advice and investigation. Lumps that suddenly appear during a viral illness (such as a cold or with flu like symptoms) are likely to due lymph glands fighting an infection and are less concerning. These are temporary and should disappear over a few days or at most a couple of weeks as an illness resolves. Lumps that persist beyond this should be investigated.
A known thyroid nodule that starts to grow rapidly also requires further assessment. A long standing hoarse voice could be a sign of a benign nodule pressing or stretching the nerve but a new or mor pronounced change in voice should again trigger investigation. Those with a family history of thyroid cancer, previous history of thyroid cancer themselves or radiation exposure to the neck should always seek early advice on any changes that are noted.
