Ossicle/Oncology

Head and Neck Oncologic Surgery

THYROID DISEASE

Medullary Thyroid Carcinoma produces calcitonin

Amyloid and leukocytic infiltrate on path
Associated with RET-protooncogene and MEN IIa and IIb

Thyroid Binding Globulin

Increases with estrogens, BCP's, pregnanacy
Decreases with androgens
High TBG = High T4, Low T3RU (T3RU inversely proportional to # unoccupied T3 binding sites)
High T3RU with hyperthyroidism, alternate ligands - salicylate, clofibrate
Low T3RU with hypothyroidism, increased TBG

T1 + T1 => T2, PLUS ADD'L T2 => T4 => T3 + T1

T4 => T3 blocked in periphery by propylthiouracil
Tyr => Iodotyrosine blocked by thiouracil
T3 much more active than T4, half life 30h
T4 less active, half life 7 days
Serum T4 = Bound + Free (free T4 is active)

Hypothyroidism - Low T4, Low T3RU

Hyperthyroidism - High T4, High T3RU

Grave's Ophthalmopathy - decompress orbits into ethmoids and maxillary sinus

Thyroiditis

Acute Suppurative - (rare), hi WBC, nl ESR; Staph, Strep, Pneumococcus
Subacute (DeQuervan's) - (common), Decr T3RU, High T3 & T4; Rx steroids, ASA
Fibrous (Reidel's) - (rare), Rx debulking, steroids, cyclophosphamide
Chronic Lymphocytic (Hashimoto's) - (common), α-microsomal and α-TBG antibodies; Rx: thyroxine
Chronic non-suppurative - (rare)