Download 1. Clinical Impression? Differentials?

1. Clinical Impression?
Differentials?
Thyroid Carcinoma
• commonly manifests as a painless, palpable, solitary thyroid nodule
• The patient's age at presentation is important because solitary
nodules are most likely to be malignant in patients older than 60
years and in patients younger than 30 years
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thyroid nodules are associated with an increased rate of malignancy in male
individuals
Malignant thyroid nodules are usually painless
Differentials:
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Papillary carcinoma
Follicular carcinoma
Hürthle cell carcinoma
Medullary carcinoma
Anaplastic carcinoma
Primary thyroid lymphoma
Metastasis
PAPILLARY vs. FOLLICULAR
Papillary Thyroid Cancer
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Follicular Thyroid Cancer
· Peak onset ages 40 through 60
Peak onset ages 30 through 50
Females more common than males · Females more common than males by 3
to 1 ratio
by 3 to 1 ratio
directly related to tumor size
Prognosis directly related to tumor · Prognosis
[less than 1.0 cm (3/8 inch) good
size [less than 1.5 cm (1/2 inch)
prognosis]
good prognosis]
· Rarely associated with radiation exposure
Accounts for 85% of thyroid cancers · Spread to lymph nodes is uncommon
due to radiation exposure
(~10%)
Spread to lymph nodes of the neck · Invasion into vascular structures (veins
and arteries) within the thyroid gland is
present in more than 50% of cases
common
Distant spread (to lungs or bones) is
· Distant spread (to lungs or bones) is
very uncommon
uncommon, but more common than with
Overall cure rate very high (near
papillary cancer
100% for small lesions in young
· Overall cure rate high (near 95% for small
patients)
lesions in young patients), decreases
with advanced age
2. Work ups
A. Physical Examination
• head and neck
• examination with careful attention to the thyroid gland
and cervical soft tissues
• Hard and fixed thyroid nodules are more suggestive of
malignancy than supple mobile nodules are.
• Thyroid carcinoma is usually nontender to palpation.
• Firm cervical masses are highly suggestive of regional
lymph node metastases.
• Vocal fold paralysis implies involvement of the recurrent
laryngeal nerve.
B. Measurement of Thyroid
Hormones
• thyroid-stimulating hormone (TSH) assay,
to screen for hypothyroidism or
hyperthyroidism.
• A low serum TSH value suggests an
autonomously functioning nodule, which
typically is benign.
• Malignant disease cannot be ruled out on
the basis of low or high TSH levels.
C. Imaging procedures
• Ultrasound also can be used to assess for cervical
lymphadenopathy and to guide fine-needle aspiration
(FNA) biopsy.
• The usefulness of ultrasonography for distinguish
between malignant and benign nodules is limited.
• Microcalcifications noted on sonograms are assoHelpful
in distinguishing solid nodules from cystic ones, and
providing information about size and multicentricity.
D. Fine-needle aspiration biopsy (FNAB)
• FNAB is highly cost-effective compared with traditional
workups like nuclear imaging and ultrasonography.
• Papillary thyroid carcinoma and MTC are often positively
identified on the basis of FNAB results alone.
• definitive surgical planning can be undertaken at the
outset.
• Patients with follicular neoplasm, as determined with
FNAB results, should undergo surgery for thyroid
lobectomy for tissue diagnosis.
3. Treatment
Surgical Treament
• Primary treatment for papillary and follicular carcinoma is
surgical excision whenever possible.
• Near-total thyroidectomy with lymph node dissection
• After thyroidectomy, patients undergo radioiodine
scanning to detect regional or distant metastatic disease
followed by radioablation of any residual disease found.
– Patient should be treated for several weeks postoperatively with
(liothyronine 25 micro grab bid-tid)
– Withdrawal for an additional 2 weeks
4. Management
Thyroid suppression
• Patients take T4 in daily doses sufficient to suppress
TSH production by the pituitary.
• Low TSH levels in the bloodstream reduce tumoral
growth rates and reduce recurrence rates of welldifferentiated thyroid carcinomas.
Follow-up care
• Patients are regularly monitored every 6-12 months with serial
radioiodine scanning and serum thyroglobulin measurements after
surgery and radioiodine therapy.
• Thyroglobulin- a useful marker of tumor recurrence because welldifferentiated thyroid cancers synthesize thyroglobulin.
• Serum thyroglobulin is measured during the withdrawal of thyroid
hormone or the administration of recombinant TSH.
• Serum antithyroglobulin antibody levels should be obtained with
each thyroglobulin measurement.
• Rising thyroglobulin level after thyroid ablation suggests recurrence.
• Ultrasonography of the neck can also be used to detect regional
recurrences.
5. Complications