2. 2010

3.  Solitary thyroid nodules are present in approximately 4 percent of the population.  Thyroid cancer has a much lower incidence of 40 new cases per1 million.  Details regarding the nodule :time of onset, change in size, pain, dysphagia, dyspnea, or choking.

4.  A history of hoarseness is worrisome because it may be secondary to malignant involvement of the recurrent laryngeal nerves.  Risk factors for malignancy, such as exposure to ionizing radiation and family history of thyroid and other malignancies.

5.  Nodules that are hard, gritty, or fixed to surrounding structures, such as to the trachea or strap muscles, are more likely to be malignant.  Afine-needle aspiration biopsy is the most important diagnostic test.

6.  B enign (65 percent),suspicious (20 percent), malignant (5 percent), and nondiagnostic (10 percent).  The incidence of false-positive results is approximately 1 percent and false negative results occur in approximately 3 percent of patients.

7.  The risk of malignancy in this setting is less than 3 percent.  The risk of malignancy in the suspicious cytology is anywhere from 10–20 percent.  FNA biopsy also is less reliable in patients who have a history of head and neck irradiation or a family history of thyroid cancer, because of a higher likelihood of cancer and coexistent benign and malignant lesions.

8.  patient with a nodule is found to be hyperthyroid, the risk of malignancy is approximately 1 percent.  Ultrasound is helpful for detecting nonpalpable thyroid nodules, for differentiating solid from cystic nodules.  CT scan & MRI are unnecessary in the routine evaluation of thyroid tumors except for large, fixed, or substernal lesions.

9.  123I or 99mTc is rarely necessary, just in “hot” or autonomous thyroid nodules.  Thyroidectomy should be performed if a nodule enlarges on TSH suppression, causes compressive symptoms, or for cosmetic reasons.

10.  patient who has had previous irradiation of the thyroid gland or who has a family history of thyroid cancer. In these patients total or neartotal thyroidectomy is recommended because of the high incidence of thyroid cancer (≥ 40 percent) and decreased reliability of FNA biopsy.

11. 18th ed.