The pituitary gland is a pea-shaped gland located in a bony structure (pterygoid saddle) at the base of the brain. The pterygoid saddle protects the pituitary gland, but leaves only a small space for its expansion. The pituitary gland produces a variety of hormones, each of which affects a specific part of the body (target organ), i.e. the pituitary gland regulates the function of most other endocrine glands. Pituitary tumors are tumors originating from anterior pituitary cells, which have insidious onset, slow progression, no elevated intracranial pressure and positive neurological signs in the early stage, and atypical clinical symptoms, which are easily missed and misdiagnosed, increasing the disability and mortality rates. Therefore, it is important to have a pair of “wise eyes” to identify pituitary tumors at an early stage.
1. Misdiagnosis as ophthalmological diseases Pituitary tumors often expand upward and compress the part of the brain that transmits visual signals, resulting in blockage of optic nerve conduction and impaired blood supply, thus causing vision loss, visual field loss and double blindness. The lateral development of the tumor may also affect the cavernous sinus, compress the 3rd nerve and cause ptosis, which may affect the optic nerve and eventually cause optic nerve atrophy. Patients with pituitary tumors often visit the ophthalmology department in the early stages due to blurred vision, vision loss, or even loss of vision.
However, the effect of pituitary tumor on visual function is reversible in the early stage, once the tumor is released and the blood supply to the optic nerve fibers is restored, the vision can be restored. For patients with decreased visual acuity and blurred vision who consult ophthalmology and are suspected of having ophthalmology or whose conventional treatment by ophthalmology is ineffective and there is no clear reason to explain, cranial MRI should be considered to exclude pituitary tumor if necessary.
Pituitary gland is the most complex endocrine gland in the body, which secretes 7 kinds of hormones, namely growth hormone (GH), prolactin (PRL), thyroid stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), gonadotropin and melanocyte stimulating hormone. On the one hand, pituitary tumors may cause hyposecretion of pituitary hormones and atrophy of the surrounding target glands due to pressure on the normal tissues outside the tumor, and on the other hand, the tumor tissue itself may secrete too many hormones and develop hyperfunction.
PRL tumors are the most common tumors of the pituitary gland, mostly seen in women aged 20 to 40 years old, and significantly more often in women than men. Pregnancy can contribute to the growth of PRL tumors, so some patients with PRL tumors are not diagnosed until after pregnancy. In men, hyper-PRLemia can cause the penis to fail to erect, manifesting as decreased libido and/or impotence. This shows that early PRL tumors are highly likely to be misdiagnosed as menstrual disorders (in women) and impotence (in men). Patients who are difficult to diagnose at the moment should be followed up and examined in order to confirm the diagnosis and receive effective treatment as soon as possible. If pituitary tumors are suspected based on clinical symptoms, endocrinological examinations and imaging examinations are feasible.
In addition to the two most common clinical misdiagnosis symptoms mentioned above, there are still some more atypical symptoms that medical practitioners and patients should be alert to.
In recent years, it has been reported and clinically discovered that pituitary tumors can cause psychiatric symptoms, epilepsy, and olfactory disturbances. Patients tend to have agitation before the onset and intermittent episodes with remission periods intact. Psychiatric disorders are closely related to the menstrual cycle, and some patients may have delusions, bizarre behavior, and other manifestations of schizophrenia. Once the patient’s psychiatric symptoms are found to be closely related to menstruation, the patient should be highly alert to the possibility of pituitary tumors.
Some of the pituitary tumors are non-secretory adenomas, which can cause fatigue, depression, loss of appetite, drowsiness, hypoglycemia and hyponatremia by affecting the secretion of gonadotropins, thyroid stimulating hormones and adrenocorticotropic hormones. The elderly themselves have reduced body functions and less specific symptoms, which can be easily misdiagnosed as other diseases by non-specialists. Non-functioning adenomas are more common in elderly patients, accounting for more than half of the patients with pituitary tumors. Therefore, in the middle-aged and elderly population, attention should be paid to the symptoms similar to those of coronary artery disease and other conditions exhibited by non-functioning adenomas.
Pituitary tumors in adults cause excessive secretion of growth hormone from the anterior pituitary gland, resulting in changes in the connective tissue of the body, excessive proliferation of bone and cartilage, hyperplasia of joint capsules, increased synovial fluid, enlarged joint cavities, rough skin, enlarged hands and feet, and thick lips and hands. Other patients may show symptoms similar to rheumatoid arthritis and osteoarthritis, which is very likely to delay the diagnosis if the history taking and physical examination are not detailed.
An analysis of the clinical presentation and diagnostic delay of patients with pituitary tumors found that the average delay in diagnosis was more than one year for patients first seen in ophthalmology and obstetrics and gynecology, and the correct rate of first diagnosis in obstetrics and gynecology and internal medicine was low. The accuracy of the first visit to male and Chinese medicine departments was zero, but the number of patients was too small to be meaningful. Therefore, improving the detection rate of non-specialties is essential to reduce the misdiagnosis of pituitary tumors.
In recent years, the incidence of pituitary tumors has been increasing year by year, and the ocular symptoms, endocrine disorders, and psychiatric symptoms caused by them have seriously affected people’s normal life and are being paid more and more attention. To reduce the misdiagnosis rate of pituitary tumor and improve the efficiency of early diagnosis is the most important clinical work at present. On the one hand, medical personnel should improve their personal treatment level, and on the other hand, patients themselves should pay attention to some abnormal manifestations of themselves and seek early treatment.