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Neoplasm of thyroid gland
L3
1- Benign neoplasm
called thyroid adenoma.
2- Malignant
include:
a. Papillary carcinoma is the most common
b. Follicular carcinoma.
c. Medullary carcinoma.
d. Anaplastic carcinoma.
Follicular adenoma:
Is a benign neoplasm of thyroid gland derived from follicular epithelium, it is usually
solitary nodule, painless, well demarcated and capsulated so careful histological
examination of capsule is very important for capsular invasion to exclude follicular
carcinoma.
The adenomas are usually non functioning so appear in radionuclide scanning as cold
nodule, but in minority of cases it may be functioning so appear by scan as hot nodule
and cause signs and symptoms of thyrotoxicosis.
Carcinoma
1- Papillary carcinoma
It is most common type of malignant neoplasm occur in thyroid gland, it is associated
with previous exposure to ionizing radiation, occur more often in young age group,
early cervical L.N metastasis occur in this type of malignancy.
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2- Follicular carcinoma:
This second most common neoplasm occur in older age group than papillary carcinoma,
the blood born metastasis are more common.
3- Medullary carcinoma
It is neoplastic transformation of parafollicular cells or C cells of thyroid gland so it is
associated with increased calcitonin level in serum of patient.
4- Anaplastic carcinoma
Among the most aggressive human neoplasm, occur usually in old age group and the
patient present with distant metastasis.
Adrenal gland
Or called suprarenal gland which's consist of 2 parts distinct embryologically,
functionally and structurally
These 2 parts are
: 1- adrenal cortex.
2- adrenal medulla
Adrenal cortex
Synthesize and secretes steroid hormones, these hormones are:
1- glucocorticoides or cortisol.
2- mineralocoticoides or aldosterone.
3- Adrenocortical androgen.
Disease of adrenal cortex also divided into :
1- Hyperadrenalism
so according to the type steroids increased this divided into
a- hypercortisolism
(Cushing syndrome)
b- b- hyperaldosteronism
this usually cause sodium retention and potassium
excretion so cause hypertension and hypokalemia,this condition either
primary to adrenal gland or secondry to activation of renin-angiotensin
system.
c- c- adrenogenital syndrome
by increased of androgen with virilization
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2- Adrenal insufficiency
This occur either
a. primary cause from adrenal cortex itself .
b. secondary due to decrease stimulation by ACTH from pituitary as in cases of
Sheehan's syndrome.
The hypoadrenalism cause Addison's disease characterized in primary cause by
hyperpigmentation because of increased ACTH precursor hormone stimulate
melanocytes so cause hyperpigmentation of face, axilla, nipple and perineum.
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Neoplasm
.
Adrenal medulla
Adrenal medulla consist of chromaffin cells responsible for synthesis and secretion of
catecholamines in response to signals from sympathetic nervous system. The most
important diseases of adrenal medulla are neoplasm these include
1- Neuronal neoplasm
as neuroblastoma
.
2- Neoplasm of chromaffin cells called
pheochromocytoma
but this neoplasm if
occur outside the adrenal glands as carotid body called paraganglioma this tumor
usually caused increased of catecholamines level so cause severe hypertension.
Good Luck
Mubark A. Wilkins