It is caused by excessive secretion of growth hormone (GH) by the adenohypophysis. In adolescents, it leads to gigantism due to the unclosed epiphyses; after puberty, when the epiphyses have fused, it results in acromegaly; a few cases that begin in adolescence and continue to develop into adulthood form acromegalic gigantism. In the early stage (formation stage), there is generalized hypertrophy of the body and internal organs, with hyperfunction of the anterior pituitary; in the advanced stage (decline stage), physical strength declines, and secondary hypofunction of the anterior pituitary occurs.

bubble_chart Diagnosis

1. Medical history, symptoms, and signs:

The onset is slow, and there may be no symptoms in the early stages. Gradually, the face becomes broader and longer, with prominent eyebrows and cheekbones, a large nose and ears, thickened lips and tongue, a protruding jaw, sparse teeth, enlarged nasal wings and larynx, dull speech, and increasingly ugly appearance. Fingers and toes become thick and short, the metatarsus thickens, the skin all over the body becomes rough, with profuse sweating and oily skin. A few may have goiter, increased basal metabolic rate, mostly normal thyroid function, and a few may have hyperthyroidism. Internal organs are generally hypertrophied, and the chest expands. Men may have increased libido, while women often experience menstrual disorders, amenorrhea, and infertility. Half may have impaired glucose tolerance, increased thirst and urination, and those with high prolactin levels may experience galactorrhea. In the advanced stage, symptoms of tumor compression may appear, including headache, visual field defects, and hypertension. Secondary hypothyroidism, secondary adrenal cortical insufficiency, gonadal atrophy, and hypogonadism, osteoporosis, and restricted spinal activity may also occur. Pituitary gigantism is characterized by excessive growth during childhood, tall stature, and rapid growth of limbs. There is increased appetite and extraordinary arm strength. In the advanced stage (decline phase), physical strength gradually weakens.

(1) GH measurement: baseline value >15ug/L, up to 100ug/L or more during active periods (normal < 5ug/L）。

(2) Significant increase in somatomedin (normal value 75～200ug/L).

(3) Increased blood sugar and decreased glucose tolerance, glucose suppression test: oral glucose 100g, blood drawn before and 1/2, 1, 2, 3, and 4 hours after glucose intake to measure GH. Normally, GH drops below 1ug/L 1 hour after glucose intake, below 5ug/L after 2 hours, and rises above 5ug/L after 4 hours. In this disease, GH secretion is autonomous and not suppressed.

(4) Calcium and phosphorus measurement: a few have increased serum calcium and phosphorus, increased urinary calcium, and decreased urinary phosphorus. Persistent or significantly high blood calcium may indicate other multiple endocrine adenoma diseases such as hyperparathyroidism.

(5) X-ray examination: enlarged head, thickened skull plate; most have enlarged sella turcica, destruction of anterior and posterior clinoid processes; enlarged sinuses, prominent occipital bone protuberance; hyperplasia at the ends of long bones, tufted hyperplasia at the top of the phalanges. CT scanning helps in detecting microadenoma patients.

3. Differential diagnosis:

Should be differentiated from pachydermoperiostosis, empty sella syndrome, etc.

bubble_chart Treatment Measures

1. Radiotherapy:

Internal and external irradiation (using deep X-rays, cobalt-60, heavy particles, etc.), 60-90% are more sensitive. X-knife and γ-knife stereotactic radiotherapy can also be used.

2. Surgical treatment:

Transsphenoidal surgery is preferable. For large adenomas or mixed tumors with extrasellar extension, combined treatment with other methods is necessary.

(1) Drugs to inhibit GH secretion:

Bromocriptine 10mg/day or more, chlorpromazine, cyproheptadine, etc., with uncertain efficacy.

(2) Sex hormones:

Can alleviate symptoms. For example, medroxyprogesterone (Depo-Provera) 8-10mg, qid; diethylstilbestrol 1mg, tid. Both can be taken alternately or simultaneously. For gigantism reaching puberty or girls with height exceeding 165cm, sex hormone therapy should be initiated to promote epiphyseal fusion.

(3) Growth hormone release inhibitors:

Octreotide, 100ug, 3 times/day, effective after 6 months.

(4) For patients in the decline phase with anterior pituitary hypofunction, appropriate hormone replacement therapy is required.