Papillary thyroid carcinoma (PTC)
- 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
Papillary thyroid carcinoma (PTC) PATHOLOGY*****
- 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
follicular thyroid carcinoma (FTC)
- 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
Medullary thyroid carcinoma
- ORIGIN FROM C-CELLs
- caused by activation point mutations in RET pro-oncogene on chromosome 10
ANAPLASTIC CARCINOMA OF THE THYROID (UNDIFFERENTEIATED CARCINOMA)
- VERY, VERY, UGLY, BOTH HISTOLIGCALLY AND CLINICALLY
- all of the cells look different then each other
Primary hyperparathyroidism general
- 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
why does excess PTH causes hypercalcemia
- 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
describe the clinical correlation of primary hyperparathyroidism****
- 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***
Parathyroid adenoma general
- most common cause of primary hyperparathyroidism
- tumors truely are monoclona
- most common in older women
- average around 1 grand
Describe testing for parathyroid adenoma
- Tc99 sestamibi nuclear imaging scan has made finding these much easier
–> minimally-invasive radioguided parathyroidectomy (MIRP)
Parathyroid hyperplasia
- 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
secondary hyperparathyroidism****************
- 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)
Parathyroid carcinoma
- 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
causes of Hypoparathyroidism
- 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
Hypoparathyroidism symptoms
- symtpoms and sign of hypocalcemia
- mental changes
- circumoral paresthesia
- Chvostek sign (low calcium)
- Trousseau sign (low calcium)
** PROGRESS TO CONVULSIONS AND TETANY **
how to diagnosis hypoparathyroidism
- confimed by finding DECREASE SERUM CALCIUM and INCREASE SERUM PHOSPHATE
- treatment includes vitamin D and calcium gluconate cookies
