Benign thyroid enlargement (non-toxic multinodular goiter): Diagnosis
A multinodular goiterGoiter - enlarged thyroid is often first found on routine physical examination or when the patient seeks medical attention for a neck mass or increased size of the neck. As with all thyroid conditions, initial evaluation includes a detailed history, specifically focusing on hypo or hyperthyroid symptoms (See Diseases of thyroid function), family history of thyroid disease, history of head and neck irradiation, and factors suggestive of malignancy. These factors include any rapid growth of the neck mass, presence of associated enlarged neck lymph nodes, or new-onset hoarseness. Physical examination of a MNGMNG - Multinodular goiter; enlarged thyroid that contains multiple nodules is used to determine the size of goiter, the possible extension of the large thyroidunder the breastbone (i.e. substernal extension), and signs of hyperfunction (rapid heart rate, irregular heart beats, tremors, etc). Most patients have normal thyroid function with nontoxic MNGNontoxic MNG - multinodular goiter that produces normal levels of thyroid hormone. Therefore laboratory examination is typically limited to TSHTSH - Thyroid stimulating hormone; also known as thyrotropin. The hormone that causes the thyroid to make and release thyroid hormone and free T4T4 - thyroxine thyroid hormone levels.
Thyroid ultrasound is an important part of evaluating a MNG. It is a good tool for assessing the size of the goiter more accurately, as well as the size and characteristics of nodules within the goiter. Ultrasound has no radiation exposure and, is therefore, completely safe. Ultrasound can also help guide fine needle aspiration (FNAFNA - fine needle aspiration biopsy) biopsy of nodules. (See Thyroid Nodule → Fine Needle Aspiration Biopsy) Nodules that would be considered for FNA biopsy include those over 1 cm in size or nodules that have certain characteristics that are worrisome for malignancy (See Thyroid nodule). These characteristics may include irregular borders, internal tiny calcium deposits (i.e. calcifications), or increased blood flow. Ultrasound and FNA biopsies should be performed by experienced personnel.