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 thyroid nodules are associated with an increased rate of malignancy in male individuals Malignant thyroid nodules are usually painless

Differentials: Papillary carcinoma Follicular carcinoma Hürthle cell carcinoma Medullary carcinoma Anaplastic carcinoma Primary thyroid lymphoma Metastasis

PAPILLARY vs. FOLLICULAR Papillary Thyroid Cancer Peak onset ages 30 through 50 Females more common than males by 3 to 1 ratio Prognosis directly related to tumor size [less than 1.5 cm (1/2 inch) good prognosis] Accounts for 85% of thyroid cancers due to radiation exposureradiation exposure Spread to lymph nodes of the neck present in more than 50% of cases Distant spread (to lungs or bones) is very uncommon Overall cure rate very high (near 100% for small lesions in young patients ) Follicular Thyroid Cancer · Peak onset ages 40 through 60 · Females more common than males by 3 to 1 ratio · Prognosis directly related to tumor size [less than 1.0 cm (3/8 inch) good prognosis] · Rarely associated with radiation exposureradiation exposure · Spread to lymph nodes is uncommon (~10%) · Invasion into vascular structures (veins and arteries) within the thyroid gland is common · Distant spread (to lungs or bones) is uncommon, but more common than with papillary cancer papillary cancer · Overall cure rate high (near 95% for small 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 well- differentiated 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 well- differentiated 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