Endocrine cancer refers to a disease where cells grow uncontrollably within the hormone-producing glands of the endocrine system. These abnormal cells can form a mass, known as a tumor, which may be benign or malignant. Malignant ones can invade nearby tissues or spread to other parts of the body. Endocrine cancers affect glands that regulate various bodily processes.
Understanding the Endocrine System
The endocrine system is a network of glands and organs that produce and release hormones into the bloodstream. Hormones act as chemical messengers, traveling throughout the body to regulate many essential processes. These processes include metabolism, growth, development, sexual function, and mood.
Key glands within this system include the pituitary gland, located at the base of the brain, and the thyroid gland in the neck, which regulates metabolism. The parathyroid glands, small glands behind the thyroid, regulate calcium balance. Adrenal glands, on top of each kidney, produce hormones involved in metabolism and stress response. The pancreas, located behind the stomach, produces hormones like insulin to regulate blood sugar. Neuroendocrine cells, which have characteristics of both nerve and endocrine cells, are found throughout the body.
Types of Endocrine Cancers
Endocrine cancers can develop in any hormone-producing glands or tissues. Thyroid cancer is the most common form of endocrine cancer, originating in the thyroid gland. These cancers, such as papillary and follicular types, often grow slowly and have favorable outcomes when diagnosed early. Medullary and anaplastic thyroid cancers are less common, with anaplastic being particularly aggressive.
Neuroendocrine tumors (NETs) arise from specialized neuroendocrine cells distributed widely, including in the lungs, appendix, small intestine, rectum, and pancreas. NETs vary in growth rate, with some being slow-growing while others are more aggressive. Pancreatic neuroendocrine tumors (PanNETs), also known as islet cell tumors, are a less common pancreatic cancer originating from the hormone-producing cells in the pancreas. These are distinct from the more common pancreatic adenocarcinomas and often have a better prognosis.
Adrenal cancer, or adrenocortical carcinoma, is a rare cancer that begins in the adrenal glands. These tumors can sometimes produce excess hormones, leading to various symptoms. Pituitary tumors develop in the pituitary gland; while most are benign, cancerous forms are very rare. These tumors can affect the production of many hormones that control other glands. Parathyroid cancer is exceptionally rare, affecting the small glands in the neck that regulate calcium levels.
Recognizing Endocrine Cancer
The signs and symptoms of endocrine cancer vary and often relate to the specific hormones produced by the affected gland or tumor. A tumor’s size can cause symptoms, such as a lump in the neck from thyroid cancer or headaches from a pituitary tumor. Many endocrine cancers also cause symptoms through the overproduction or underproduction of hormones. For instance, adrenal cancers can lead to weight changes and muscle weakness due to excess cortisol, while parathyroid cancer may cause fatigue and bone pain from high calcium levels.
Diagnosing endocrine cancer involves reviewing symptoms and medical history, followed by a physical examination to check for any masses or unusual signs. Laboratory tests are often performed to measure hormone levels or tumor markers in the blood, which can indicate an imbalance or the presence of specific cancer cells. Imaging scans, such as CT, MRI, or PET scans, help visualize the tumor’s size and location. A biopsy, taking a tissue sample, is the definitive method to confirm a cancer diagnosis.
Managing Endocrine Cancer
Treatment for endocrine cancer is individualized, considering the specific type of cancer, its stage, location, and whether it is producing hormones. Surgery is often the primary treatment option, aiming to remove the tumor and any affected surrounding tissue. For example, thyroid cancer often involves surgical removal of part or all of the thyroid gland.
Following surgery, or as standalone treatments, other therapies may be utilized. These include radiation therapy, which uses high-energy beams to destroy cancer cells, and chemotherapy, which uses anti-cancer drugs for aggressive or widespread cancers. Targeted therapy drugs focus on specific weaknesses within cancer cells, while immunotherapy helps the body’s immune system fight the cancer. Hormone therapy is relevant for endocrine cancers, as it can help stop tumor growth or manage symptoms by controlling hormone levels. For some slow-growing neuroendocrine tumors, a “watch and wait” approach with regular monitoring might be appropriate.