1.Pituitary Tumor
Pituitary tumors are almost always benign tumors that can be cured.
2.The causes of symptoms in patients with pituitary tumors
Excessive secretion of hormones
Local occupancy effect
Residual normal pituitary tissue cannot provide sufficient hormone level
3.Types
Pituitary tumors include the following (in descending order of frequency)
(1) Functional adenoma
(2) Prolactinoma
(3) Growth hormone tumors
(4) Adrenocorticotropic hormone tumors
(5) Thyrotropinoma
(6) Luteinizing hormone/follicle stimulating hormone tumor
4. Hormone production
The common tumors with hormonal activity mainly include
(1) Acidophilic growth hormone-type adenomas, basophilic adrenocorticotropic hormone-type adenomas and prolactin-type adenomas. These tumors can grow through the pituitary fossa (pterygoid saddle).
(2) Pro-adrenocorticotropic tumors: basophilic adenomas presenting as Cushing’s syndrome (Cushing’s syndrome) with slowly increasing tumors. The tumor is initially confined to the pterygoid saddle, but may increase in size or even become invasive after removal of both adrenal glands (Nelson’s syndrome).
(3) Prolactin-type adenoma: It is commonly an intra-saddle growth, which can be small (less than 10mm) but can also enlarge and enlarge the pterygoid saddle.
(4) Growth hormone-type tumors: eosinophilic, often leading to gigantism in childhood and acromegaly in adults. Suprasellar extension is not uncommon and grows slowly.
(5) Non-functional tumor: It grows across the pterygoid saddle and compresses the surrounding tissue structures to produce symptoms, so it does not show endocrine symptoms. Visual disturbance is the common first manifestation.
5.Epidemiology
The annual incidence of clinically symptomatic pituitary tumors is approximately 1-2 cases per 100,000 population.
Considering some undiagnosed cases, the actual incidence may be higher.
6. Clinical presentation
Depends on the hormonal type of the tumor and the growth pattern in the saddle.
Focal symptoms due to tumor growth.
Growth in the pituitary fossa can lead to headache, neurological visual field defects or facial pain, depending on the size of the tumor and the direction of its growth
(1) Headache: The typical location is posterior to the globe or bilateral temporal side, aggravated by walking. Sudden and severe headaches are often caused by pituitary tumor stroke (pituitary tumor hemorrhage). Large pituitary tumors can cause obstruction of cerebrospinal fluid circulation, leading to hydrocephalus and enlargement of the lateral ventricles.
(2) Visual field defects: common but often unrecognized by the patient. Bilateral temporal hemianopsia is the classic presentation, but unilateral or bilateral visual field defects can also occur.
(3) Actinic nerve palsy can lead to strabismus.
(4) Invasion of the hypothalamus often leads to decreased appetite, irritability, abnormal thermoregulation, and impaired consciousness.
(5) Early manifestations of pituitary hormone deficiency.
Total pituitary hypofunction or six hormone deficiencies its momentary occurrence
Hypopituitarism often occurs in the following order: luteinizing hormone (LH), growth hormone (GH), thyrotropin (TSH) and finally, a decrease in adrenocorticotropic hormone (ACTH) and follicle stimulating hormone (FSH) levels.
Common symptoms in adults are infertility, amenorrhea, decreased libido and erectile dysfunction. Luteinizing hormone and growth hormone deficiencies can lead to muscle atrophy, decreased body hair, centripetal obesity and smaller testes.
Hypopituitarism in children often manifests as delayed puberty or growth retardation.
Diabetes mellitus and enuresis are rare symptoms but often occur after pituitary tumor surgery.
Overproduction of pituitary hormones can often lead to acromegaly, hyperprolactinemia, Cushing’s disease, and hyperthyroidism.
7.Checkup
Endocrine examinations may identify reduced or increased hormone levels.
Lateral cranial X-ray: Occasionally an enlarged pituitary fossa may be found, but the diagnosis is not conclusive.
Visual field examination: upper temporal quadrant blindness and bilateral temporal lateral hemianopsia are common.
MRI is superior to CT. 10% of the normal population can be examined for microscopic lesions in the pituitary fossa (pituitary ependymoma), and the presentation is consistent with pituitary microadenoma.
8.Differential diagnosis
The remaining common tumors in the saddle area are craniopharyngioma, lacunar cyst, and the relatively uncommon meningioma, germ cell tumor, and malformation tumor. [3]
Craniopharyngioma is a benign cystic tumor growing on the saddle. It presents with headache, visual field defects and pituitary hypoplasia (which manifests as growth disturbances because it often occurs in children and adolescents).
Other diseases that can cause headache, visual field defects, visual impairment and endocrine dysfunction.
9. Treatment
Treatment depends on the type of tumor and whether it invades the surrounding brain tissue. Hormone-secreting tumors can be treated with surgery, radiation therapy or drugs such as bromocriptine (for prolactin adenomas) or growth inhibitors (for growth hormone-type adenomas).
10. Surgery
The vast majority (about 95%) of non-functional pituitary tumors and adrenocorticotropic pituitary tumors are treated with transnasal butterfly surgery. A small number of patients require craniotomy. Large nonfunctional pituitary tumors often grow beyond the pituitary borders and require combined radiotherapy for treatment. Emergency surgery is often required for rapid deterioration of vision.
11.Radiotherapy
Suitable for.
Lesions that have not been completely resected and cannot be completely resected by reoperation
Patients with hypersecretion status after surgery
12.Growth inhibitor analogues
These drugs, such as octreotide acetate and lanreotide, are the main drugs used in the treatment of growth hormone pituitary tumors, and are also used in rare thyrotropin pituitary tumors. Octreotide and lanotide can control hormone secretion in most patients with acromegaly and can even shrink tumors.
Bromocriptine
The application of bromocriptine has been successful in treating patients with prolactinotropic pituitary tumors. The dopamine agonists cartegolide and quigolide (not yet introduced in mainland China) have been successfully used in patients who have relapsed or failed after bromocriptine treatment, with minimal side effects. Adrenal steroid hormone inhibitors, such as mitotane, ketoconazole, can also be applied while waiting for radiotherapy to work.
13.Recurrent pituitary tumor
Patients with recurrence after surgery can be operated again or treated with radiation therapy.
Certain selected patients with recurrence can be treated with radiotherapy again for long-term control of focal symptoms, such as improvement or maintenance of visual status.
14. Complications
Pituitary tumor stroke – sudden onset of hypopituitarism due to acute infarction or hemorrhage of a pituitary adenoma.
15.Prognosis
After treatment, 90% of patients with microadenoma and 50-60% of patients with macroadenoma can be cured or in remission.