Transcript ارائه دهنده:دکتر خسرو روانخواه 3

2010
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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 .
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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 .
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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 .
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Benign (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.
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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.
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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 .
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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.
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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 .
18th ed.