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Question 1

Papillary thyroid carcinoma (PTC)

Answer 1

• OFTEN MULTIFOCAL cancer (multiple tumors)
• common in ADULTS
• IRRADIATING the thyroid gland gives an increased rate of papillary carcinoma
• increased risk form radioactive iodine therapy of graves disease is very small

Question 2

Papillary thyroid carcinoma (PTC) PATHOLOGY*****

Answer 2

• Papillary adenocarcinoma = fibrovascualr stalk with tumor cells
• Pathologists usually see the ORPHAN ANNIE EYE nuclei

–> marginated chromatin and optically clear centers

–> its a fixation artifact

• another favorite finding is psammoma bodies (calcification)
• Intranuclear cytoplasmic inclusion AKA “nuclear hole”
• Nuclear groves AKA “coffee bean” nucleus

Question 3

follicular thyroid carcinoma (FTC)

Answer 3

• MORE aggressive thyroid carcinoma
• there are NO FIBROVASCULAR PAPILLAE, NO ORPHAN ANNIE EYE, NO PSAMMOMA BODIES
• GRossly, it may be obsiously malignant or may have already metastasized

- METASTASIZE TO LUNG AND BONE

- More often malignancy is established by demonstrating that a thyroid nodule contains groups of cell INVADING VESSELS

Question 4

Medullary thyroid carcinoma

Answer 4

- ORIGIN FROM C-CELLs

• caused by activation point mutations in RET pro-oncogene on chromosome 10

Question 5

ANAPLASTIC CARCINOMA OF THE THYROID (UNDIFFERENTEIATED CARCINOMA)

Answer 5

• VERY, VERY, UGLY, BOTH HISTOLIGCALLY AND CLINICALLY
• all of the cells look different then each other

Question 6

Primary hyperparathyroidism general

Answer 6

• MOST common reason is parathyroid galnd adenoma
• characterized by LESIONS WITHIN the parathyroid gland that secret excessive amounts of PTH

–> atuonomous overproduciton of PTH NOT suppressed by the negative feedback inhibition of elevated serum calcium

Question 7

why does excess PTH causes hypercalcemia

Answer 7

• increase bone resorption and calcium mobilizaton from bone
• increase renal tubular reabsorption of calcium in the urine (hypercalciuria - so much calcium that it cant all be absorped

–> predisposes to renal stone formation so that flank pain and hematuria can occur

• increase urinary excretion of phosphate
• increase renal synthesisi of vitamine D, thereby enhancing calcium absorption in the gut

Question 8

describe the clinical correlation of primary hyperparathyroidism****

Answer 8

• KIDNEY STONES = most common presentation
• Bone changes = Osteitis fibros cystica (brown tumors)
• Increase serum calcium on routine screening

–> probably the most common presentation today

–> hypercalcemia also stimualtes gastrin relase and icnrease acid secertion from gastric pareital cells –> PEPTIC ULCER DISEASE

• Mental changes (depression, psychosis)
• Just not feeling right (muscle weakness, fatigues)

*** renal STONES, painful BONES, abdominal GROANS, mental MOANS***

Question 9

Parathyroid adenoma general

Answer 9

• most common cause of primary hyperparathyroidism
• tumors truely are monoclona
• most common in older women
• average around 1 grand

Question 10

Describe testing for parathyroid adenoma

Answer 10

• Tc99 sestamibi nuclear imaging scan has made finding these much easier

–> minimally-invasive radioguided parathyroidectomy (MIRP)

Question 11

Parathyroid hyperplasia

Answer 11

• 2nd most important cause of primary hyperparathyroidism

–> ALL 4 GLANDS ARE BIG, for no obvious reasons

–> hyperplastic galnds usually lack the usual fat cells

• this may occur in anyone, but is suspcious for one of the MULTIPLE ENDOCRINE NEOPLASIA (MEN) syndromes
• Histopathology = NO RIM OF NORMAL PARATHYROID TISSUE AT ALL

Question 12

secondary hyperparathyroidism****************

Answer 12

• parathyroidism hyperolase due to HYPOCALCEMIA from some OTHER CUASE
• Most often CHRONIC RENAL FAILURE (CRF) causing secondary hypersecretion of PTH

–> DECRESE CALCIUM + INCREASE PTH

- BONE DISEASE = is a big problem (renal osteodystrophy –> brown tumors)

Question 13

Parathyroid carcinoma

Answer 13

- 50% cured by en bloc resection

• mean time to recurrence approximately 33 months (3 years)

** THICK FIBROUS BANDS in 90%

** 80% of pts have MITOTIC ACITIVITY**

- 65% have CAPSULAR INVASION

• small percent have vascular invasion

Question 14

causes of Hypoparathyroidism

Answer 14

• most common cause is AUTOIMMUNE
• other causes = Iatrogenic (surgical misadventure)
• less common cause = DiGeorge Syndrome = because of failure of descent of 3rd and 4th brachial pouches resultin gin parathyroid agenesis

Question 15

Hypoparathyroidism symptoms

Answer 15

• symtpoms and sign of hypocalcemia
• mental changes
• circumoral paresthesia
• Chvostek sign (low calcium)
• Trousseau sign (low calcium)

** PROGRESS TO CONVULSIONS AND TETANY **

Question 16

how to diagnosis hypoparathyroidism

Answer 16

• confimed by finding DECREASE SERUM CALCIUM and INCREASE SERUM PHOSPHATE
• treatment includes vitamin D and calcium gluconate cookies