A

Figure 1-5. An asymptomatic patient presents with a swelling in the central neck that moves with deglutition. A, The goiter is classified as World Health Organization stage II. B, Photomicrograph of a fine-needle aspirate from the goiter reveals normal cellularity, abundance of colloid, and no signs of atypia (hematoxylin and eosin; x400 original magnification).

Dyshormonogenesis, goitrogens whether natural or in the form of medications such as lithium, and radiation result in goiters in some patients. Furthermore, a gene linked to the familial form of MNG has been mapped to the short arm of chromosome 14.6

Many patients with MNG are asymptomatic, but some may present with local pressure symptoms exerted by the goitrous gland on neck structures such as the trachea or the esophagus.7 Rarely, hoarseness would result from acute stretching of the recurrent laryngeal nerve by the goitrous gland, but when a patient has a thyroid nodule and recurrent laryngeal nerve palsy, thyroid cancer is most likely. A positive Pemberton's sign (facial flushing and dilation of the jugular veins owing to decreased venous drainage from the head and neck on raising the arms above the head) should raise suspicion of a substernal extension (Figure 1-6). An inspiratory stridor indicates tracheal compression, and flow loop studies can be done to confirm this diagnosis. The World Health Organization (WHO) classifica-

Figure 1-6. Pemberton's sign of facial plethora is demonstrated by asking the patient to raise both arms above the head, obstructing the venous drainage from the head and neck at the thoracic inlet.

Table 1-1. WHO CLASSIFICATION OF GOITER

Stage Description

0-A No goiter

0-B Goiter detected by palpitation but not visible when the neck is extended

I Goiter is palpable and visible only with neck extension

II Goiter is visible in normal position

III Larger goiter seen at a distance

WHO = World Health Organization.

tion of goiter in Table 1-1 is helpful to describe the size of the thyroid gland (Figure 1-7).

Most multinodular goiters are asymptomatic and are noted because of a swelling in the thyroid area. Patients with goiters should be questioned about a family history of familial thyroid cancer or radiation exposure. Patients should be asked if they have any local symptoms such as pain, hoarseness, a change in voice or dysphagia, or systemic symptoms of hyper-or hypothyroidism. A serum TSH level should be obtained to determine whether the patient is euthy-roid, hypothyroid (elevated TSH), or hyperthyroid (suppressed TSH). The latter occurs in patients with autonomous hyperfunctioning nodules. Testing of thyroid function is especially important in elderly patients who may have apathetic hyperthyroidism to avoid the detrimental effect of untreated thyrotoxico-sis on the cardiovascular system and bones.

Ultrasonographic examination of the neck and thyroid gland often reveals many subclinical nodules, even in patients thought to have a solitary nodular goiter. Patients with multinodular goiters are less likely to have cancer than are patients with solitary nodules, although dominant nodules arising in MNG carry nearly the same risk of malignancy as those arising in normal glands. In a patient with a dominant or solitary nodule, fine-needle aspiration (FNA) for cytologic examination is the most cost-effective method to determine whether the nodule is benign, suspicious, or malignant. Computed tomography and magnetic resonance imaging (MRI) are not usually needed, except in some patients with substernal goiters and to help plan the extent of the surgical operation (Figure 1-8). Radioiodine scanning is rarely indicated, except in patients with cytologic evidence of follicular neoplasms because thyroid cancer is rare when the nodules are hot or autonomous.

Figure 1-7. The patient presented with a long-standing swelling in the lower part of the neck. History revealed increasing neck discomfort in the recent past. A, Note the multinodular appearance of a World Health Organization stage III goiter. B, Multiple nodules are seen in the total thyroidectomy specimen. C, A multilocular cyst was deroofed to show areas of necrosis and hemorrhage.

Figure 1-7. The patient presented with a long-standing swelling in the lower part of the neck. History revealed increasing neck discomfort in the recent past. A, Note the multinodular appearance of a World Health Organization stage III goiter. B, Multiple nodules are seen in the total thyroidectomy specimen. C, A multilocular cyst was deroofed to show areas of necrosis and hemorrhage.

Patients with endemic goiter benefit from iodine or thyroid hormone replacement. However, they should be followed carefully as some may develop jodbasedow (iodine-induced) hyperthyroidism. T4 should be used to reduce blood TSH levels to the low normal range in patients with an elevated TSH. Treatment with thyroid hormone to lower TSH levels works better in patients with diffuse or small goiters or nodules than in patients with larger nodules. The target TSH level should be 0.1 to 1.0 mU/L in young patients and about 1.0 mU/L in older patients. Although treatment with thyroid hormone appears to decrease goiter size in about 25 to 50% of patients, it also appears to prevent some goiters from growing.8

Surgical therapy is indicated in patients with local symptoms, lesions proven or suspicious for being malignant on FNA, recurrent cysts, history of familial nonmedullary thyroid cancer or irradiation, patient anxiety, and an enlarging lesion while on thyroid hormone and for cosmetic reasons (Fig ure 1-9). We recommend surgery in most patients with substernal goiters, even in the absence of symptoms, because most patients are likely to develop symptoms in the future when the gland enlarges, and some patients develop acute respira-

Figure 1-8. Chest computed tomographic scan in a patient with a substernal goiter and significant stridor. Note that the gland is compressing the airway down to the level of the carina.

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