What are the major parts of endocrine system?

Surgical options when a gland goes awry

Stubbled chin and neck closeup

The body’s endocrine system includes the pituitary gland, thyroid gland, parathyroid glands and the adrenal glands.

The pituitary gland is a kidney-bean-sized gland situated at the base of your brain. The thyroid gland is a small, butterfly-shaped gland in the lower front of your neck. Also in the neck are four oval-shaped glands called the parathyroid glands. Two adrenal glands are just above each kidney in the back of the upper abdomen. Finally, the pancreas, ovaries and testicles also are part of the endocrine system.

The endocrine system regulates hormone levels in your body. Hormones act like messengers. They are released into your bloodstream to give instructions to another organ. Hormones control many biological processes, like your blood sugar, energy, body growth, metabolism, body temperature, heart rate and protein production.

Two branches of medicine treat conditions of the endocrine system: endocrinologists and endocrine surgeons.

Physicians who specialize in endocrinology, called endocrinologists, can evaluate and treat endocrine disorders using treatments like medications, hormone replacement therapies or nutrition therapies. Endocrine surgeons have completed specialized training in the surgical care of conditions affecting the endocrine system. They work closely with endocrinologists and can perform surgery if medical treatments are not effective.

Conditions treated

Endocrine surgery is used to treat benign and malignant diseases of the endocrine system. Benign conditions are not cancerous and don’t spread to other parts of the body. However, they can cause damage due to excessive hormone production or due to local compression.

Some benign conditions include:

  • Hyperparathyroidism
    There are four parathyroid glands in the neck, and they are responsible for regulating calcium levels in your blood. This condition occurs when one or more of the parathyroid glands secretes hormones in an uncontrolled manner. Over time, this can damage your kidneys, bones, gastrointestinal system and central nervous system. In many cases, the best solution is surgical resection of the affected gland or glands.
  • Hyperthyroidism and Graves’ disease
    If your thyroid releases too many hormones, you have an overactive thyroid. This is also called hyperthyroidism. It can cause sudden weight loss, fast or irregular heart rate, sweating and irritability. Graves’ disease is an immune system disorder that leads to hyperthyroidism. Graves’ disease can cause weight loss, heat sensitivity, irritability, changes in sexual health, bulging eyes, fatigue, red skin, rapid heart rate and sleep disturbances. In selected cases, surgery could be the best cure.
  • Goiter
    A goiter is an enlargement or irregular growth of the thyroid gland. Usually, a goiter doesn’t change thyroid function or hormone levels. However, such an enlargement might cause local compression symptoms that might result in breathing difficulties or become cosmetically bothersome and require surgical resection.
  • Thyroid nodules
    This common condition is a growth in the thyroid gland. Although most of the time, nodules are benign and do not warrant a surgical intervention, a diligent evaluation should be conducted to identify and treat those nodules that appear more suspicious
  • Adrenal nodule
    Another common condition is a lump on the adrenal gland. It is often discovered during a cross-section CT or MRI. Adrenal nodules are usually benign and rarely malignant. However, in many cases, they require a surgical resection due to excess hormone production. Thyroid nodules may be evaluated by ultrasound to determine if they are suspicious for malignancy. In some cases, a fine needle aspiration biopsy will be necessary. In this procedure, cells from the lump are collected using a thin needle and analyzed under a microscope. About 80% of thyroid nodules are benign, about 10% are cancerous, and about 10% are indeterminate. This means that a repeat biopsy or surgery may be needed to confirm the diagnosis.

Malignant tumors are tumors that grow in an uncontrolled manner and have the potential to invade surrounding tissues and spread, or metastasize, to other parts of the body.

Most people with cancer in the endocrine system will undergo surgery to remove all or part of the gland. This includes:

Which operation your health care team recommends will depend on your type of cancer, the size of the cancer and other characteristics, and whether the cancer has spread to adjacent tissues or nearby lymph nodes.

Endocrine surgery

Surgery is not always necessary to treat benign endocrine conditions. Medications and other nonsurgical treatments are effective for many people. Surgery may be necessary if these other treatments are ineffective.

The kind of surgery you have will depend on your issue and the affected gland. For example, thyroid surgery could remove half of the gland, called a lobectomy, or all of the gland, called a thyroidectomy. A near-total thyroidectomy also could be performed, where almost all the gland is removed. Your surgeon may not know how much thyroid gland must be removed until the surgery.

Often, parathyroid conditions are caused by one or more parathyroid glands. In this case, usually only the affected glands will be surgically removed. Then the normally functioning glands will remain in place.

If a gland is removed completely, you’ll need to take hormones for the rest of your life to replace your natural hormones. This lessens side effects once your health care team finds the right dose for you.

Surgical advancements

Endocrine surgery is safe. Two significant surgical advancements for thyroid and parathyroid surgery have improve surgical effectiveness. The first is continuous interoperative nerve monitoring to protect the recurrent laryngeal nerve. This nerve is adjacent to the delicate structures of these glands. It controls a person’s vocal cords. Damage during surgery can cause long-lasting side effects ranging from voice hoarseness to an obstruction of the airway. With continuous interoperative nerve monitoring, the nerve’s function is checked during surgery so your surgeon can modify techniques or strategy to avoid nerve damage.

Another advancement is called rapid intraoperative parathyroid assay. One of the properties of the parathyroid hormone is that it lasts in the bloodstream for a short time, often only about four and a half minutes. During surgery, the team checks this hormone level in the operating room. A decline in levels of that hormone can indicate if the team has the correct gland to remove or if further exploration is necessary.

Sometimes, people are confused if they should seek care from an endocrine surgeon; an otorhinolaryngologist, also called an ear, nose and throat specialist; or a urologist. The areas of the body cared for by these professionals overlap, as the thyroid and parathyroid glands are in the neck and the adrenal glands are adjacent to the kidneys. The main advantage of an endocrine surgeon is specialized training in the comprehensive treatment of disorders of the endocrine system.

Your primary care provider can help refer you to the appropriate specialist to meet your needs.