Condition / Morphology / Clinical Course / Additional Notes / Diff Dx
Pituitary adenoma / Well-circumscribed lesion
Often compress optic chiasm
If Invasive: foci of hemorrhage & necrosis
Relatively uniform, polygonal cells arrayed in sheets or cords. Sparse reticulin (CT)
F(x)al status CANNOT be predicted by histologic appearance / Endocrine abnormalities & mass FX
Radiographic abnormalities of sella turcica
Visual field abnormalities—bitemporal hemianopsia
Elev’d intracranial pressure—w/ HA, N/V / Peak incidence 30s-50s
Assoc’d w/ MEN 1
Micro < 1 cm in diameter
Macro >1cm in diameter
Acute hemorrhage into an adenoma=pituitary apoplexy / Hyperplasia of pituitary
Carcinoma of pituita
ry
Prolactinoma / Weakly acidophilic or chromophobic cells
PRL w/in secretory granules / Hyperprolactinemia—amenorrhea, galactorrhea, loss of libido, and infertility / Most frequent hyperf(x)ing pit. Adenoma (lactotrophs)
Serum [PRL] proportional to size of adenoma
Ages 20-40, more freq Dx in women
Tx: bromocriptine—causes lesions to diminish in size / HyperPRL:
Pregnancy
Lactating ♀
Lactotroph hyperplasia
Stalk effect from other masses
Drugs: DA receptor antagonists (phenothiazines, haldol), reserpine, estrogens
Renal failure
Hypothyroidism
Growth Hormone Adenoma / Granulated cells, acidophilic or chromophobic
Immunohistochemical stains demo GH w/in cyto of neoplastic cells / If in kids b4 epiphysis close: gigantism—gen’d increase in body size, disprop. Long arms and legs
If inc’d levels of GH after closure:
Acromegaly—most conspicuous in skin & soft tissues, hyperostosis ini spine & hips, prognathism / Mutant GTPase?
GH excess correlated w/: gonadal dysf(x), DM, gen’d muscle weakness, HTN, arthritis, CHF, & inc’d risk of GI cancers.
Tx: surgical removal thru transphenoidal approach, radiation therapy, or drug therapy
Corticotroph Cell Adenomas / Small microadenomas
Basophilic or chromophobic
Stain w/ PAS
Produce XS ACTH / XS ACTH—hypercortisolism (Cushing syndrome)
Hyperpigmentation due to inc’d ACTH / Nelson syndrome: when large destructive adenomas develop after surgical removal of the adrenal glands for Tx of Cushing syndrome
Diabetes Insipidus / ADH deficiency / Polyuria, polydipsia
Excretion of large volumes of dilute urine w/ low specific gravity
Inc’d serum Na
Inc’d serum osmolality / Head trauma
Tumors
Inflamm d/o of hypothalamus & pituitary
Syndrome of inappropriate ADH secretion (SIADH) / XS ADH / Hyponatremia
Cerebral edema
Neurologic dysf(x)
Normal blood volume, but total body water is increased / Secretion of ectopic ADH by SCLC, non-neoplastic dz of lung, & local injury to hypothalamus or posterior pituitary
Hyperthyroidism / Elevated levels of free T3 & T4
Low TSH in primary / Nervousness
Palpitations
Rapid pulse, cardiomegaly
Fatigability
Muscular weakness (prox)
Wt loss w/ good appetite
Diarrhea
Heat intolerance
Warm skin
XSive perspiration
Emotional lability
Menstrual changes
Fine tremor of the hand
Inability to concentrate
Insomnia, osteoporosis / Cardiac manifestations are the earliest & most consistent features
Thyrotoxic cardiomyopathy
A normal rise in TSH after admin’d of TRH excludes secondary /
  1. Diffuse hyperplasia of thyroid gland assoc’d w/ Graves dz
  2. Ingestion of exogenous TH
  3. Hyperf(x)al multinodular goiter
  4. Hyperf(x)al adenoma of the thyroid
  1. Thyroiditis
  2. Ovarian teratoma

Hypothyroidism / Cretinism
myxedema / Radiation injury, Surgical ablation, Hashimoto Thyroiditis, Iodine deficiency
Drugs (Li, P-ASA), Pituitary lesions reducing TSH secretion, Hypothalamic lesions, Hemochromatosis, Amyloidosis, Sarcoidosis
Cretinism / Hypothyroidism in infancy or early childhood / Imprd devmnt skeletal system & CNS—severe MR, short stature, coarse facial features, a protruding tongue, & umbilical hernia / Dietary iodine deficiency
Maternal thyroid deficiency
Myxedema / Hypothyroidism in older kids and adults / Vary with age of onset
Slowing of physical & mental activity
Gen’d fatigue, Apathy
Mental sluggishness
Slowed speech & mental f(x)s
Listless, cold intolerance
SOB, dec’d exercise capacity
Constipation
Decreased sweating
Edema
Broadening & coarsening of facial features
Enlargement of the tongue
Deepening of the voice / Dec’d serum [T3] & [T4]
Condition / Pathogenesis / Morphology / Clinical Course / Additional Notes
Hashimoto Thyroiditis / Diffusely enlarged gland
Capsule is intact
Well-demarcated margins
Pale, gray-tan, firm, & somewhat nodular
Mononuclear infiltrate—small lymphs, PCs

Well-dev’d germinal ctrs

Hurthle cells
Inc’d interstital CT
Fibrosis does NOT extend beyond capsule / Painless enlargement of the gland
Hypothyroidism
May be preceded by transient thyrotoxicosis
Elev’d free T4 & T3 levels
Low TSH
Decreased radioactive uptake
Abs to thyroglobulin & thyroid Peroxidase, TSH receptor, possible iodine transporter / Inc’d risk for dev’ing B-cell lymphomas
Most common cause of hypothyroidism
Gradual thyroid failure
Autoimmune destruxn of gland
Ages: 45-65
More common in women
HLA-DR5, HLA-DR3
Primarily a defect in T cells
Apoptosis med’d by Fas-FasL system (induced by IL-1β)
Subacute (granulomatous) Thyroiditis / Involved areas are frim & yellow-white and stand out from more rubbery, normal brown thyroid substance
Changes are patchy
PMNs forming microabscesses

Multinucleate giant cells

/ Hx of URI b4 onset?
Sudden or gradual
Pain in the neck, which may radiate to the upper neck, jaw, throat or ears, particularly when swallowing.
Fever, fatige, malaise, anorexia, and myalgia
High serum T3 & T4
Low serum TSH
Low radioactive uptake / Ages:30-50
More common in women
Caused by a viral infexn or postviral inflamm process
Peaks in summer
HLA-B35
Subacute
Lymphocytic
Thryoiditis / Thyroid normal on gross inspexn
Multifocal inflamm infiltrate—small lymphs, patchy disruption, & collapse of thyroid follicles / Painless
Mild hyperthyroidism OR goitrous enlargement
High serum T3 & T4
Low serum TSH
Low radioactive uptake
Elev’d levels of Abs to thyroglobulin & thyroid Peroxidase / Middle-aged women, esp postpartum
HLA-DR3 & DR5
Graves Dz / Autoimmune disorder by AutoAbs to the TSH receptor or to thyroid-stimulating Igs / Symmetrically enlarged
Diffuse hypertrophy & hyperplasia of follicle epithelial cells

Too many cells

Colloid w/in lumen is pale w/ scalloped margins
Tissues of orbit are edematous / Thyroid enlargement
Audible bruit over thyroid
Characteristic wide, staring gaze and lid lag
Exophthalmos
Proptosis
Pretibial myxedema—scaly thickening & induration of skin
High serum T3 & T4
Low serum TSH

Increased radioactive uptake

/ Most common cause of endogenous hyperthyroidism
Ages: 20-40
Women 7X more common
HLA-B8 & -DR3
Diffuse Nontoxic (simple) goiter / Involves entire gland w/o producing nodularity
Iodine deficiency /

Hyperplastic stage

Colloid involution

/ Elev’d TSH
Multinodular goiter / Irregular enlargment of thyroid
Produce the most extreme thyroid nodules /

Multilobulated, asymmetrically enlarged gland

Intrathoracic or plunging goiter
Irregular nodules containing variable amts of brown, gelatinous colloid
Colloid rich follicles lined by flattened, inactive epithelium and areas of follicular epithelial hypertrophy and hyperplasia / Sx caused by mass FX—may cause airway obstruxn, dysphagia, and compression of large vessels in the neck and upper thorax / Plummer syndrome—hyperthyroidism w/ toxic multinodular goiter