A pituitary tumor is a benign or malignant irregular growth that develops in the pituitary gland. This gland is located at the base of an individual's brain. It is responsible for the regulation of all the other glands located throughout the body. The pituitary gland carries out these functions through making and excreting various hormones, including growth hormone, thyroid-stimulating hormone, prolactin, vasopressin, and oxytocin. Aside from rare hereditary cases, the cause of pituitary tumor development is not known.
Pituitary tumor treatment depends on the type, location, and severity of the tumor. Some patients will have surgery to remove the pituitary tumor. Radiation therapy for pituitary tumors is also fairly common. Hormone medications and tumor-shrinking medications may also be used to treat pituitary tumors.
An individual who has a smaller size pituitary tumor will not typically experience vision problems. However, individuals who have pituitary tumors larger than one centimeter in diameter may develop vision loss in one or both of their eyes. Sometimes certain components of their vision will become compromised, such as peripheral vision. Another common vision issue that occurs in pituitary tumor patients is double vision.
An individual's eyes are situated a few centimeters in front where the pituitary gland is housed. This is an area referred to as the pituitary sella. Two thick bands made up of hundreds of nerve fibers connect the eyes to the brain, allowing visual data to travel to the brain where it is processed. A pituitary tumor that is large enough can compress one or both of these optic nerve cables. The compression can result in a disruption of data impulses between the eyes and the brain. This malfunction is what produces visual symptoms.
Headaches may be directly provoked in individuals with a pituitary tumor by entering an area referred to as the cavernous sinus. The cavernous sinus is a region of the brain that houses the first and second trigeminal nerves. Compression of these nerves can cause a headache because they are sizeable cranial nerve bundles that dictate the sensation in the face.
Other pituitary tumor patients may experience headaches when the tumor begins to affect the area of the brain and neck where the meninges are located. Cancer infiltration near or into the meninges can cause inflammation of these membranes, which results in subsequent swelling and pain in the back of the head. Furthermore, individuals who have a pituitary tumor causing the gland to decline in function tend to develop vascular headaches due to the pituitary hormone shortage.
Weight Loss Or Gain
A common symptom of a pituitary tumor is sudden weight loss or gain. Several different types of pituitary tumors can cause unexplained weight loss or weight gain. Adenoma tumors that secrete too much ACTH hormone can cause a patient to gain weight in their belly, chest, and face. Pituitary tumors referred to as thyroid-stimulating hormone-secreting adenomas cause increased production of thyroid-stimulating hormone. This increased production results in an overactive thyroid gland. A common symptom that occurs in patients who have high thyroid-stimulating hormone levels is unexplained weight loss.
Pituitary tumors referred to as macroadenomas damage parts of an individual's pituitary gland and result in a shortage of one or more pituitary hormones in the body. Low levels of these hormones can result in either unexplained weight loss or unexplained weight gain, depending on which hormone or hormones are being affected.
A pituitary tumor patient may experience excessive sweating. Some affected individuals only sweat excessively at night, while others experience constant sweating. Some patients may have pituitary tumors that secrete an excessive amount of thyroid-stimulating hormone. This hormone is responsible for telling the thyroid gland to make more thyroid hormones. Thyroid hormones help maintain and manage an individual's metabolism, heart rate, breathing rate, energy use, and multiple other processes.
Sweating is a common symptom that occurs with the production of excessive amounts of thyroid hormone in the body because of increased heat production. The faster metabolism and increased speed of other bodily processes can result in an inappropriate increase in body temperature because heat is given off with energy use. Sweating is the body's mechanism to cool itself down when it becomes too hot as a result of the pituitary tumor-precipitated increase in body temperature.
Nausea And Vomiting
Pituitary tumors may produce nausea and vomiting through numerous mechanisms. A pituitary tumor that presses on the nerves that allow for communication between the eyes and vision center of the brain can cause visual problems and disturbances that result in nausea and vomiting. Any tumor that puts pressure on the brain can cause nausea and vomiting due to a headache, reduced blood flow, or inappropriate activation of the vomiting center in the brain.
Pituitary tumors that damage the parts of the gland responsible for producing hormones such as cortisol and thyroid-stimulating hormone are also known to cause nausea and vomiting. Decreased TSH or cortisol from damage to the gland can cause several body systems to slow down, including the gastrointestinal system. When food stagnates in the digestive tract for too long, the patient may begin to feel nauseous or vomit. Deficient amounts of these hormones in the body can also reduce an individual's heart rate and breathing. This leads to nausea and vomiting due to low blood pressure and dizziness.
An individual who presents with mood changes may be affected by a pituitary tumor. Mood swings in an individual in response to their everyday stresses and situational circumstances are normal. When mood changes begin to become so severe that they interfere with daily tasks and responsibilities, it can indicate a more serious medical problem.
A tumor in the pituitary gland can cause it to produce too much stimulating hormone, forcing the adrenal glands to make excess cortisol. When an individual's body is exposed to high levels of cortisol over a long period, they develop a syndrome referred to as Cushing syndrome. A Cushing syndrome patient can experience symptoms, including a loss of emotional control, anxiety, depression, irritability, fatigue, and severe mood swings.
Unusual And Unexplained Fatigue
Fatigue characterizes when an individual feels like they do not have any energy to carry out their normal daily functions. The energy in an individual's body is produced by the cells through certain processes that require a steady supply of certain nutrients and substances. Oxygen and glucose are the two main elements in the body that are required for the cells to produce usable energy. They come from the food an affected individual consumes.
Cancerous cells in a tumor growing somewhere within an individual's body are also made of cells that require usable energy. However, a pituitary tumor will not leave enough oxygen and glucose for the other healthy cells in the body to use. This mechanism causes the individual to feel unusually weak and fatigued.
Anxiety And Depression
One of the most common causes of anxiety and depression is a condition referred to as hypothyroidism. Hypothyroidism is a condition in which the thyroid gland does not produce an adequate amount of thyroid hormone. Depression and anxiety in hypothyroidism patients are also commonly paired with tiredness and fatigue. Secondary hypothyroidism occurs when the pituitary gland does not produce enough thyroid-stimulating hormone. Remember, this hormone is responsible for telling the thyroid to produce more thyroid hormones when they become too low.
A tumor that develops in the pituitary gland can cause the cells responsible for producing thyroid-stimulating hormone to be unable to carry out this function. This mechanism can cause an affected individual to develop anxiety and depression due to pituitary tumor-precipitated hypothyroidism.
Increased Urine Output
A patient with a pituitary tumor may present with unusual increased urine output. The kidneys are the organs responsible for making urine. They are stimulated to produce urine when the brain releases antidiuretic hormone. The rear-most part of the pituitary gland is responsible for the production of antidiuretic hormone when fluids need to be retained instead of excreted through urine.
An individual affected by pituitary cancer may experience difficulty with their pituitary gland producing an adequate amount of antidiuretic hormone when it is needed. When the pituitary gland cannot produce enough antidiuretic hormone, the kidneys will continue to filter fluids into the urine even when the body needs to retain it. This malfunction results in increased urine output.
High Blood Sugar
An individual who has developed a tumor in their pituitary gland may experience high blood sugar. The body has mechanisms in place that are meant to increase blood glucose when it falls too low for the brain to function. When blood sugar becomes too low, the pituitary gland produces a hormone that tells the adrenal glands to produce cortisol. Cortisol functions with adrenaline to increase the amount of sugar in the blood so it is more available for the muscles to use when the individual has a fight or flight reaction.
However, a tumor of cancerous cells that develops in the pituitary gland can cause it to release too much of the hormone that commands the adrenal glands to produce cortisol and adrenaline. This malfunction results in the excessive production of cortisol and adrenaline in the blood by the adrenal glands. This causes an individual's blood sugar to become and remain too high.