1. -Worldwide, the most common cause for goitre is iodine deficiency. In countries that use iodized salt, Hashimoto's thyroiditis is the most common cause. -Hypothyroidism have INCreased Sec. of TRH and TSH-->work as a thyroid growth hormone --> Thus, Goiter is more likely with hypothyroidism. - Any Thyroid Mass is Investigated by : 1st:TSH & Free T4, 2nd:US w/ Bx. if mass is more then 1cm, 3ed: Thyroid uptake scan. -FNAC Bx. any thyroid nodule if= normal TSH+nodule size is more the 1 cm -Thyroid Nodule U/S is more accurate than CT! - lower margin of mass can not be felt = mass maybe extending to the mediastinum = r/o CA - Bx Any Thyroid mass 1cm or more, if less then 1cm mass follow-up every 12 months.
2. 1st: Near total thyroidectomy especially if more then 1cm, if less then 1cm lobectomy can be done ,2nd: Radio-active iodine Rx, 3ed: high dose thyroxin to keep TSH@ 0.1-0.3; followup with Thyro-globulin(Tg) levels & Total body thyroid scan
3. @ Midline
   1. Moves with tongue protrusion
      1. Dx. Thyroglosal Duct Cyst
         1. Must r/o ectopic thyroid tissue(w. U/S, Ct, or Scans) before Surgery
4. enlarged thyroid gland=Goiter
   1. focal mass= Multi-nodular=One Nodule
      1. MCC is asymptomatic insignificant incidental finding
         1. Follow up with U/S every 6-12 months
      2. mass w/ S/S of hard on palpation , local compression to vocal cords or esophagus, irregular, painless = CA until proven otherwise!!!
         1. slow growing
            1. Psammona bodies+Lymphatic spread
            2. Dx.PapiLLary
            3. Capsular vasCUlar invasion & spread
            4. Dx.FolliCUlaR
            5. Hyper-Ca, & Hyper-Calcitonin
            6. Medullary
            7. r/o MEN IIa(Hyperparathyroidism, pheochromocytoma)
            8. Rx. 1st remove pheochromocytoma if present, 2nd. total thyroidectomy & Central Node dissection at infancy if Dx.MEN IIb, and surgery by age 5 years if Dx.MEN IIa
            9. r/o MEN IIb ( mucosal neuromas, marfanois, Pheochromocytoma)
         2. Rapidly growing mass=w/in 4 weeks
            1. Undifferentiated Bx.
            2. Anaplastic CA
            3. Rx. Palliative Chemo-radiation
            4. w / Hx. Hashimoto's thyroiditis
            5. Dx. NON-Hodgkin's Thyroid Lymphoma
            6. Rx. curative Radiation & Chemotherapy
   2. Generalized= Diffused
      1. Hashimoto's
      2. Grave's
      3. Thyroiditis