Disclaimer: While every
attempt is made to ensure the accuracy of the information contained
herein, a certain amount of conjecture is admitted. For a complete
understanding, please consult your physician, and or endocrinologist
for a more detailed understanding. Excerpts are taken from a
variety of information sources, including the Textbook of Medical-Surgical
Nursing by Brunner, Emerson, Ferguson, and Suddarth 2nd Edition,
and informational pamphlets from the Thyroid Foundation of America,
Inc. plus other sources, dictionaries, etc.
Since this Glossary is for Thyroid
Cancer Group patients, perhaps the first step is the identification
of the four different types of thyroid cancer: papillary, follicular
(most common, mixed papillary-follicular), medullary (solid,
with amyloid struma), and anaplastic (rare).
B C D E
F G H I J
K L M N O
P Q R S T
U V W X Y Z
Removal of a body part or the destruction of its function, as
by a surgical procedure, morbid process, or noxious substance.
anaplastic carcinoma: accounts
for 10% or less of thyroid cancer and occurs mostly in elderly
patients, females slightly more than males. The tumor is characterized
by rapid and painful enlargement, and about 80% of patients
die within 1 year of diagnosis. Rapid enlargement of the thyroid
gland may also suggest thyroid lymphoma, particularly if found
in association with high concentrations of thyroid antimicrosomal
antibodies and Hashimoto's thyroiditis.
antithyroid agents: Drugs;
methamazole (Tapazole) or Propylthiouracil (PTU), drugs used
to make it more difficult for iodine to get into your thyroid
anxiety: Apprehension of
danger and dread accompanied by restlessness, tension, tachycardia,
and dyspnea unattached to a clearly identifiable stimulus.
Assay: different labs use
different scales of measurement. This is why, for comparison,
it is crucial to be sure that the same lab, or at least the
same scale, is used for every draw. It also means that you cannot
compare your results to someone else's and make any useful conclusion;
it's all apples and oranges.
blocking agents: drugs which block the action of the thyroid
hormone on your body.
biopsy: procedure of obtaining
a tissue sample from a suspect area often used in the determination
of whether the tissue is cancerous or not.
a normal cell produced by the body which helps regulate
the balance of calcium between the blood and bones. When mtc
patients prove to be cancer free, it is likely they will not
have a 'normal' calcitonin level. The docs don't know why this
is. The goal, then, is not to get back to the 'norm', but to
level out. If you happen to get back to 'norm,' that's great;
it's also very unusual.
cancer: basically normal
cells multiplying at an uncontrolled rate.
carcinogen emryonic agent (CEA):
most cancers also produce it, which is a marker for the
presence of cancer. Everyone has a certain level of carcinogens
in the blood stream because of trace amounts of carcinogens
that we inhale, eat, etc. When it gets above a certain "norm,"
however, it is indicative that a tumor is present. MTC often
produces CEA - but not always.
CAT: Abbreviation for computerized
C-cell: have nothing to
do with thyroid functions; they just happen to reside there.
Among other things, they produce a normal hormone called "calcitonin,"
which helps regulate the balance of calcium between your blood
CT: Abbreviation for computed
cyst: an abnormal collection
of fluid within a definite sac or wall.
cytomel: drug T3 based drug.
Dermal abrasion, the surgical planning of the skin. The
procedure involves the removal of the epidermis and some superficial
dermis while preserving enough of the dermis to allow re-epithelialization
of the dermabraded areas.
Diffuse toxic goiter: Hyperthyroidism.
endocrinologist: One who
specializes in endocrinology, A specialist who studies the endocrine
glands, these include the thyroid gland, parathyroid glands,
the pancreas, the adrenal gland, and the pituitary gland.
endometrioid carcinoma: adenocarcinoma
of the ovary or prostate resembling endometrial adenocarcinoma,
possibly arising from ovarian foci of endometriosis.
eosin: A derivative of flourescein
used as a fluorescent acid dye for cytoplasmic stains and counterstains
in histology and in Romanovsky-type blood stains.
eosinophilic: Staining readily
with eosin dyes; denoting such cell or tissue elements.
euthyroid: normal thyroxine
level condition, thyroid hormone level in normal balance.
exophthalmos: a thyroid
related condition where one or both of the eyes may appear protruded.
This is a less common condition associated with Graves' disease.
for follicle-stimulating hormone. Follicular carcinoma accounts
for about 15% of thyroid cancer and is more common in the elderly.
It is more malignant than papillary carcinoma, spreading hematogenously
with distant metastases. It also is occasionally associated
with a history of radiation exposure and is more frequent in
females than in males. Treatment for follicular cancer of any
size requires near-total thyroidectomy with postoperative radioiodine
ablation of residual thyroid tissue similar to the patient with
papillary cancer. Metastases appear to be more amenable to radioiodine
follicullar thyroid cancer:
The normal thyroid gland is made up of sphere-shaped structures
called follicles. When a thyroid cancer arises from the cells
which normally make up these follicles, the cancer is called
free T4: The FT4 measures
the concentration of free thyroxine, the only biologically active
fraction, in the serum. The free thyroxine is not affected by
changes in concentrations of binding proteins such as TBG and
thyroid binding prealbumin. Thus such conditions as pregnancy,
or estrogen and androgen therapy do not affect the FT4.
goiter: a chronic enlargement
of the thyroid gland, not due to a neoplasm, occurring endemically
in certain localities, especially mountainous regions, and sporadically
Graves: is the type of hyperthyroidism
caused by a generalized overactivity of the entire thyroid gland.
It is also called "diffuse toxic goiter,", diffuse
because because the entire thyroid gland is involved in the
disease process; "toxic" because the patient appears
hot and flushed, as if feverish due to an infection; and "goiter"
because the thyroid gland enlarges in this condition. One potential
symptom is that the eyes may appear enlarged due to the elevation
of the upper eye lids.
struma: also referred to as Reidel's struma, chronic thyroiditis.
Hurthle Cells: Hürthle cell,
Askanazy cell; a large, granular eosinophilic cell derived from
thyroid follicular epithelium by accumulation of mitochondria,
e.g., in Hashimoto's disease.
hyper: see hyperthyroidism.
hyperthyroidism: The term
used to refer to any condition in which there is too much thyroid
hormone in the body. This most commonly results from a generalized
over-activity of the entire thyroid gland, a condition also
known as diffuse toxic goiter or Graves' disease. Common symptoms
may include nervousness, irritability, increased perspiration,
thinning of your skin, fine brittle hair, and muscular weakness
especially involving the upper arms and thighs. Your hands may
shake and your heart may race. Your bowel movements may increase
in frequency, though diarrhea is uncommon.
hyperparathyroidism: The presence of excess parathyroid hormone in the body resulting in disturbance of calcium metabolism with increase in serum calcium and decrease in inorganic phosphorus, loss of calcium from bone, and renal damage with frequent kidney-stone formation.
hyperplasia: numerical hypertrophy;
quantitative hypertrophy; an increase in number of cells in
a tissue or organ, excluding tumor formation, whereby the bulk
of the part or organ may be increased. See also hypertrophy.
hypo: see hypothyroidism.
hypoparathyroidism: Deficiency of parathyroid hormone (PTH) in the body. Decreased levels of PTH lead to low levels of calcium and high levels of phosphorus in the blood. This imbalance can lead to problems with bones, muscles, skin, and nerve endings.
hypothyroidism: a condition
in which the amount of thyroid hormones in the body is below
normal. This is the most common form of thyroid function abnormality,
and is far more common than an overactive thyroid. Symptoms
include feeling run down, slow, depressed, cold, tired, and
you may lose interest in normal daily activities. Other symptoms
may include dryness and brittleness of the hair, dry and itchy
skin, constipation, muscle cramps, and increased menstrual flow
for luteinizing hormone.
levothroid: drug; different
brands of the thyroid hormone T4 or levo-thyroxine.
Levoxyl: drug; different
brands of the thyroid hormone T4 or levo-thyroxine.
lobectomy: Excision of a
lobe of any organ or gland.
lymph node: lymphonodus.
lymphonodus: lymph gland;
lymph node; lymphaden; lymphoglandula; nodus lymphaticus; one
of numerous round, oval, or bean-shaped bodies located along
the course of lymphatic vessels, varying greatly in size (1
to 25 mm in diameter) and usually presenting a depressed area,
the hilum, on one side through which blood vessels enter and
efferent lymphatic vessels emerge. The structure consists of
a fibrous capsule and internal trabeculae supporting lymphoid
tissue and lymph sinuses; lymphoid tissue is arranged in nodules
in the cortex and cords in the medulla of a node, with afferentessels
entering at many points of the periphery
malignant: (1) Resistant
to treatment; occurring in severe form, and frequently fatal;
tending to become worse and lead to an ingravescent course.
(2) In reference to a neoplasm, having the property of locally
invasive and destructive growth and metastasis.
malignancy: The property
or condition of being malignant.
medullary: medullar; relating
to the medulla or marrow.
Medullary (solid) carcinoma:
of the thyroid may occur as a sporadic form (usually unilateral)
or as a familial form (frequently bilateral), transmitted as
an autosomal dominant trait. Patients are usually 15 years of
age. Pathologically there is a proliferation of parafollicular
cells ("C" cells) that produce excessive calcitonin,
a hormone that can lower serum Ca and phosphate (PO4), and there
are characteristic amyloid deposits that stain with Congo red.
Metastases are via lymphatics to cervical and mediastinal nodes,
but there may also be metastases to liver, lungs, and bone,
with dense calcifications. The usual presentation is that of
an asymptomatic thyroid nodule, although many cases are now
diagnosed during routine screening of affected kindreds with
multiple endocrine neoplasia (MEN) types II or III before a
palpable tumor develops. Medullary carcinoma of the thyroid
may have a dramatic biochemical presentation when it is associated
with ectopic production of hormones such as ACTH, vasoactive
intestinal polypeptide, prostaglandins, kallikreins, and serotonin.
This tumor is a component of Sipple's syndrome, which is characterized
by medullary carcinoma of the thyroid, pheochromocytoma, and
hyperparathyroidism. All 3 disorders are not always found in
the same patient. Pheochromocytoma is present in 50 to 75%;
hyperparathyroidism, in 50%. Additional findings not regularly
associated with this syndrome include disorders of the neural
ectoderm, including mucosal neuromas; megacolon; pectus excavatum;
poorly developed musculature; and marfanoid appearance, with
long arms and fingers. When these associated conditions occur,
the syndrome is classified as MEN, type III; hyperparathyroidism
is not present in this subset.
Medullary Thyroid Cancer (MTC):
C-cells multiplying at an uncontrolled rate creating an increasing
number of cells producing calcitonin. By measuring this overproduction,
the docs can tell if you have mtc. As yet, there is no established
correlation between the calcitonin level and the amount of tumor;
the only conclusion that can currently be drawn from an increasing
level is the continuing presence of MTC, not an increase in
metastases: (1) The shifting
of a disease, or its local manifestations, from one part of
the body to another, as in mumps when the symptoms referable
to the parotid gland subside and the testis becomes affected.
(2) The spread of a disease process from one part of the body
to another, as in the appearance of neoplasms in parts of the
body remote from the site of the primary tumor; results from
dissemination of tumor cells by the lymphatics or blood vessels,
or by direct extension through serious cavities or subarachnoid
or other spaces. (3) Transportation of bacteria from one part
of the body to another, through the bloodstream (hematogenous
metastasis) or through lymph channels (lymphogenous metastasis).
MRI: Magnetic Resonance
nodule: A small node. See
(1) a small node. (2) The posterior extremity of the inferior
vermis of the cerebellum, forming with the velum medullare posterius
the central portion of the flocculonodular lobe.
(1) Hidden; concealed; not manifest. (2) Denoting
a concealed hemorrhage, the blood being so changed as not to
be readily recognized. See occult blood. (3) In oncology, a
clinically unidentified primary tumor with recognized metastases.
cordis; forcible pulsation of the heart, perceptible to the
patient, usually with an increase in frequency or force, with
or without irregularity in rhythm.
papilla: a nipple-like projection.
Papillary carcinoma is the
most common thyroid malignancy (60 to 70% of all thyroid cancers).
Females are affected 2 to 3 times more often than males. It
is more frequent in the young, but it takes a more malignant
course in the elderly. It is often associated with a history
of radiation exposure and spreads via the lymphatics. Lateral
aberrant thyroid rests may be found that are actually occult
metastases with a benign histologic appearance. These well-
differentiated cancers are highly TSH-dependent and may develop
in hypothyroid glands secondary to Hashimoto's thyroiditis.
Many papillary cancers contain follicular elements, but this
does not alter the basic biology of the tumor. Treatment for
small (< 1.5 cm), encapsulated tumors localized to one lobe
is lobectomy and isthmectomy. Thyroid hormone in suppressive
doses is given to minimize chances of regrowth or produce regression
of any microscopic remnants of papillary carcinoma; surgery
is almost always curative. Large (1.5 cm) or diffusely spreading
tumors require total or near-total thyroidectomy with postoperative
radioiodine ablation of residual thyroid tissue with 150 mCi
131I administered when the patient is hypothyroid. Repeat treatment
may be required every 6 to 12 months to achieve ablation of
remaining thyroid tissue. Replacement doses of L-thyroxine are
given afterward at an average oral dose of 100 to 150 µg/day.
papillary carcinomas: multiple
projections giving them a fern or frond-like appearance. In
a small state these are commonly found in most thyroids, when
these papillary carcinoma grow enough to form a lump in the
thyroid gland, it is considered clinically important for it
is likely to continue to enlarge and may spread elsewhere in
the body. Such papillary tumors make up about 60% to 70% of
all thyroid cancers, and can occur at any age.
papillary: Relating to,
resembling, or provided with papillae.
parathyroid: (1) Adjacent
to the thyroid gland. (2) Glandula parathyroidea.
pathological: (1) Pertaining
to pathology. (2) Morbid or diseased; resulting from disease.
PET scan: Positron Emission
Tomagraphy; identifies differences in how quickly cells metabolize
glucose. Apparently cancer cells metabolize glucose more quickly
than normal cells.
An inflammation of the thyroid gland which normally occurs after
the birth of a child, for reasons unknown normally after the
second or later birth. It is presumedly cause by antibodies
(proteins) in the body which attack and damage the thyroid gland.
This is a common disorder which frequently goes unrecognized.
Propranolol: drug; Inderal.
for Radioactive Iodine.
radioactive iodine: usually
administered in the form of a capsule or in water (it is odorless
and tasteless), the Radioactive iodine is quickly take up by
the overactive thyroid cells. The results is that the thyroid
shrinks in size, the thyroid hormone production falls, and blood
levels return to normal with restoration of good health. Occasionally
a second treatment is given to further control the thyroid hormone
output. After administration your Nuclear Medicine technician
will usually monitor the amount of intake by the thyroid (scanning),
and looking for hot spots or glows.
resin T3 uptake: The resin
T3 uptake is used to assess the binding capacity of the serum
for thyroid hormone. This is used to help determine if the Total
T4 is reflecting the free T4, or if abnormalities in binding
capacity are responsible for changes in T4 values.
blood test to determine if the Medullary Thyroid Cancer is sporadic
or familial (hereditary)
the lab tests can run the test on the same sample of blood twice
and get two slightly different numbers. Remember, they are counting
tiny hormone levels; the digits are bound to be different each
time. What counts is how far different.
Synthroid: drug; different
brands of the thyroid hormone T4 or levo-thyroxine.
thyroglobulin: (1) iodoglobulin;
thyroprotein; a thyroid hormone-containing protein, usually
stored in the colloid within the thyroid follicles; biosynthesis
of thyroid hormone entails iodination of the tyrosine moieties
of this protein and the combination of two iodotyrosines to
form thyroxine, the fully iodinated thyronine; secretion of
thyroid hormone requires proteolytic degradation of thyroglobulin,
with the attendant release of free hormone. (2) A substance
obtained by the fractionation of thyroid glands from the hog,
Sus scrofa, containing not less than 0.7% of total iodine; used
as a thyroid hormone in the treatment of hypothyroidism.
thyroid: (1) Resembling
a shield; denoting a gland (glandula thyroidea) and a cartilage
of the larynx (cartilago thyroidea) having such a shape. (2)
The cleaned, dried, and powdered thyroid gland obtained from
one of the domesticated animals used for food and containing
0.17 to 0.23% of iodine; used in the treatment of cretinism
and myxedema, in certain cases of obesity, and in skin disorders.
of the thyroid gland.
thyroid storm: thyrotoxic
thyroidectomy: The surgical
removal of part or all of the thyroid gland.
thyroxine: The hormone produced
by the thyroid gland.
T3: see Triiodothironine
T4: see Thyroxine.
TMJ: Abbreviation for temporomandibular
Total T3: The total T3 measures
the concentration of triiodothyonine in the serum. The T3 is
increased in almost all cases of hyperthyroidism and usually
goes up before the T4 does. Thus the T3 is a more sensitive
indicator of hyperthyroidism than the Total T4. In hypothyroidism
the T3 is often normal even when the T4 is low. The T3 is decreased
during acute illness and starvation, and is affected by several
medications including Inderal, steroids and amiodarone. This
test measures both bound and free hormone. Only the free hormone
is biologically active, but is only 0.5% of the total. Anything
which affects thyroid binding globulin (TBG), or albumin will
affect the total Triiodothyronine but not the free.
Total T4: The T4 test measures
the concentration of Thyroxine in the serum. This includes both
bound and free hormone. Only the free hormone, about 0.05% of
the total, is biologically active. Anything which affects levels
of thyroid binding globulin (TBG), albumin, or thyroid binding
prealbumin will affect the total thyroxine but not the free
hormone. Estrogens and acute liver disease will increase thyroid
binding, while androgens, steroids, chronic liver disease and
severe illness can decrease it.
TRH test: Abbreviation for
TSH: Thyroid Stimulating
Hormone is secreted from the pituitary gland to stimulate the
thyroid gland. Once the thyroid gland starts secreting thyroid
hormones, these hormones reach the pituitary and decrease the
secretion of TSH in a perfect feed-back loop. Normal ranges
fall between 0.35 - 5.50.
TSH test: a more sensitive
thyroid hormone test which makes the TRH test unnecessary.
toxicosis , thyroid toxicosis; hyperthyroidism resulting
from excessive circulating 3,5,3-triiodothyronine.
Tyrosint: a drug; one of the different brands of the thyroid hormone T4 or levothyroxine.