Category Archives: Thyroid

Tall Cell Variant of Papillary Thyroid Cancer

Prognosis for the tall cell variant of papillary carcinoma

Tall cell variant of papillary thyroid cancer has been shown to be more aggressive and have a worse prognosis than the typical papillary thyroid cancer.

See more info regarding papillary thyroid cancer and other thyroid cancers.

Favorable characteristics for papillary thyroid cancer

  • age less than 50 for women
  • age less than 40 for men
  • tumor less than 5 cm.

Types of Thyroid Cancer

Five main types of Thyroid Cancer

  1. Papillary Carcinoma (80%)
  2. Follicular Carcinoma (10%)
  3. Medullary Carcinoma (5%)
  4. Hurthle Cell Carcinoma (4%)
  5. Anaplastic/Undifferentiated Carcinoma (1-2%)

P’s of Papillary Thyroid Cancer:

  • Popular (most common type – 80%)
  • Psammoma bodies
  • Palpable Lymph Nodes – common
  • Positive Iodine 131 uptake
  • Positive Prognosis
  • Postoperative Iodine 131 to diagnose / treat metastasis if a total thyroidectomy was done.

F’s of Follicular Cancer of the Thyroid

  • Far away metastasis (spreads hematogenously)
  • FNA NOT (FNA cannot be done to diagnosis Follicular Cancer of the thyroid
  • Female predominance (3:1)

M’s of Medullary Cancer of the Thyroid

  • MEN II (Multiple Endocrine Neoplasia type II)
  • aMyloid
  • Median Lymph Node dissection
  • Modified neck dissection if lateral nodes are positive
  • Secretes Calcitonin
  • Stimulated by Pentagastrin
  • Cancer of the Thyroid C cells = parafollicular cells

Calcitonin (tumor marker for MTC)

  • Reduces blood levels of Calcium
  • Opposed the effects of PTH (parathyroid hormone)
  • Calcitonin is used as a tumor marker for medullary thyroid cancer (MTC)

Pentagastrin

  • Pentagastrin has effects like gastrin
  • Pentagastrin is used as a stimulation test to elevate serotonin levels and cause symptoms of carcinoid syndrome, provoking flushing.
  • Pentagastrin has been used to stimulate ectopic gastric mucosa for the detection of Meckels diverticulum by nuclear medicine.
  • Pentagastrin-stimulated calcitonin test is a diagnostic test for MTC (Medullary carcinoma of the thyroid).  In patients with suspected MTC but borderline levels of calcitonin, injecting pentagastrin will cause calcitonin levels to rise tremendously.

 

Thyroid Anatomy
Thyroid Anatomy

Picture from: http://www.washingtonendocrineclinic.com/Thyroid-Care.html

 

 

Neck Anatomical Zones for Cancer and Trauma

Neck Zones for Cancer

When thinking of neck zones, there are those zones used in trauma and there are those used for cancer surgery.

The neck zones or levels depicted here are for cancer surgery.  Lymph nodes or neck masses in these areas are described using these locations:

anatomical zones of neck
Picture copied from internet

  • In patients presenting with solid neck masses – those masses associated with the thyroid move with swallowing.  Those in levels 3,4, and 5 do not move with swallowing.
  • Metastatic lymph nodes found in level 6 – could come from thyroid.
  • U/S and FNA should be performed after exam/history for Solid Neck Mass.
  • With well differentiated thyroid cancers, there is a high rate of cervical metastasis particularly with papillary cancers.
  • With lateral lymph nodes involved in thyroid cancer, survival rate is not improved significantly with LN dissection in the neck for patients older than 60 years old or for men with a 4 cm or larger well differentiated cancer.
  • Prophylactic lymph node dissections does not seem to improve survival with patients undergoing thyroid cancer treatment.
  • If thyroid tumor is small with documented (U/S) lateral lymph nodes.  There is a benefit to dissecting level 3 or 4 lymph nodes (lymph node dissection or modified dissection) in the younger patient.

Trauma neck zones

picture copied from internet:

neck.zones

 

Post operative hypocalcemia

Low Calcium after thyroidectomy

  • Most common complication after total or near total thyroidectomy is hypocalcemia due to hypoparathyroidism.  Post thyroidectomy hypoparathyroidism is usually related to disruption of the blood supply to parathyroid glands.
  • A patient needs only a single healthy parathyroid gland to have normal parathyroid function.

Symptoms of hypocalcemia

  • Could be asymptomatic or show up as:
  • mild paresthesias
  • Painful tentany
  • muscle aches
  • weakness or twitching
  • Larngeal spasm
  • Arrythmia

PTH

  • Parathyroid hormone measurement after surgery.  Possibly consider this protocol.  If less than 10 (pg/ML) supplement with calcium and calcitriol.  If between 10-20 supplement with calcium.  If greater than 20 – then no supplementation.
  • PTH is secreted by the chief cells of the parathyroid gland.
  • Acts to increase the concentration of calcium in the blood
  • PTH half life is about 4 minutes.

what is Calcitriol?

  • Hormonally active form of vitamin D.
  • After thyroidectomy, supplimentation with Calcitriol may supress PTH levels.

A main reason for hospitalization overnight after  total thyroidectomy

To monitor for the risk of hypocalcemia.