Paraneoplastic syndromes are diseases that arise due to the presence of cancerous tumors. A specific syndrome is usually triggered by the immune system's response to the cancer, and it may affect a system or part of the body that is entirely separate from the physical tumor. The most common paraneoplastic syndromes affect the nervous or endocrine system. Symptoms range from fever and weakness to impaired functioning of the heart and gastrointestinal tract. Most syndromes are relieved when the underlying tumor is effectively treated with surgery, chemotherapy, or radiation.
The immune system releases antibodies in an attempt to combat cancerous tumors, known as neoplasms. A paraneoplastic syndrome results when these antibodies mistakenly attack healthy tissue in other parts of the body. In addition, a paraneoplastic response can be triggered by the hormones and proteins that are produced by cancerous cells. Many different types of cancer can trigger these syndromes, though they are most common in lung, ovary, and breast cancer patients. Doctors cannot reliably predict when they will arise, and they are typically not discovered until patients exhibit physical symptoms.
Antibodies that are released to control the spread of cancer sometimes wrongly attack brain and nerve cells. Resulting paraneoplastic syndromes often lead to a range of debilitating neurological problems. An individual may have difficulties walking, controlling motor movements, seeing, and speaking. Dizziness, headaches, and numbness in the extremities are common, and some people suffer from dementia and seizures.
The body's endocrine system, which includes the pineal, thyroid, adrenal, and reproductive glands, can be affected by the abnormal hormones secreted by cancerous tumors. Paraneoplastic syndromes can impair the production and release of normal hormones, causing fever, fatigue, and poor liver and kidney functioning. A common syndrome that closely resembles Cushing's disease can result in facial swelling and a noticeable buildup of fat in the abdomen. Other paraneoplastic syndromes can cause high blood pressure, heart palpitations, abdominal pain, and gastrointestinal problems.
In many cases, the appearance of a paraneoplastic syndrome is detected before the underlying tumor is noticed. A doctor who observes common symptoms of a particular syndrome can conduct further studies to identify the presence of cancer. Treatment measures are typically geared at removing the tumor, thereby alleviating the accompanying paraneoplastic syndromes. Depending on the size and location of the tumor, a doctor might recommend surgical removal, chemotherapy, or radiation treatments. Lingering symptoms of paraneoplastic disorders may be treated with immunosuppressive drugs to control hormone and antibody production.