Pituitary tumors are lumps that form in the pituitary, a small gland about the size of a pea that sits inside the skull, just below the brain and above the nasal passages. The pituitary gland produces hormones that control the levels of other hormones secreted by endocrine glands throughout the body, giving it an important role in controlling key body functions and the hormonal system.
The pituitary gland is made up of four parts: the anterior (front) lobe and posterior (back) lobe, which function independently of each other, as well as the intermediate area between the two lobes and the stalk that connects the pituitary to the interbrain (which includes the thalamus, hypothalamus and epithalamus). Most pituitary tumors form in the anterior lobe. They very rarely develop in the posterior lobe. Pituitary tumors represent 9 to 12 percent of all primary brain tumors.
The vast majority of pituitary tumors are pituitary adenomas, benign growths that do not spread beyond the skull. Even though these tumors are not cancerous, they often cause other medical issues because they are located near the brain and may cause the pituitary to produce excess hormones.
Pituitary cancers, called pituitary carcinomas, are very rare—only a few hundred have been documented in the United States, according to the American Cancer Society. Because pituitary cancers and benign adenomas look very similar under a microscope, the carcinomas are often diagnosed only when they spread to other parts of the body.
Pituitary tumor symptoms
The signs and symptoms of pituitary tumors often mimic those caused by other medical conditions. That’s why it is important to consult a medical professional for an accurate diagnosis. Common symptoms include:
- Changes in vision
- Changes in menstrual cycles
- Overproduction or underproduction of breast milk
- Cushing’s syndrome, a condition marked by weight gain, high blood pressure, diabetes and bruising
- Unexplained tiredness
- Mood changes
Treatments for pituitary tumors
Pituitary cancer treatment options vary widely, depending on a number of factors, including the stage of the disease and the symptoms and side effects the patient may be experiencing. Patients who have no symptoms and whose hormones are functioning normally may opt for active surveillance, where they are monitored closely for signs of tumor growth or the disease’s progression. The most common treatment for pituitary tumors is surgery, most often with the surgical oncologist removing the tumor by accessing it through the nasal passages. If the entire tumor could not be removed with surgery, radiation therapy may be used to destroy remaining tumor cells.