A paraneoplastic syndrome represents a concomitant disease of a cancer. However, it is not a consequence of the tumor but develops in parallel with it. At times, the typical symptoms of a paraneoplastic syndrome indicate a malignant tumor that is still undetected and initially asymptomatic.
What is a paraneoplastic syndrome?
A paraneoplastic syndrome is always a concomitant disease to a malignant tumor. It never develops primarily as a result of a neoplasm. Sometimes the symptoms of a paraneoplastic syndrome already occur without tumor-related disease symptoms already being noticeable. Thus, the typical symptoms of certain paraneoplastic syndromes can often facilitate the diagnosis of the actual cancer. The symptoms are not a direct consequence of space occupation or tissue destruction by the tumor. Rather, they develop as a result of the increased tumor-induced release of certain agents. These can be hormones, antibodies, enzymes or inflammatory factors. Accordingly, the individual clinical pictures present themselves in a variety of ways. Paraneoplastic syndromes affect, among others, the endocrine system, the skin, the digestive system, the nervous system, the blood or the joints. Many typical symptoms do occur without an underlying cancer. However, some paraneoplastic syndromes are found exclusively in association with cancer.
Causes
The cause of paraneoplastic syndrome is thought to be the increased formation and release of biologically active substances. Thus, there are paraneoplastic syndromes that resemble typical endocrine disorders because the tumor produces increased levels of certain hormones. Endocrine paraneoplastic syndromes are caused, among others, by neuroendocrine tumors in the pancreas. These include the so-called insuloma with an overproduction of insulin, gastrinoma with an increased production of gastrin, which stimulates gastric acid production, or vipoma with severe therapy-resistant diarrhea. About 20 percent of all tumor patients develop a paraneoplastic syndrome. Bronchial carcinomas account for the largest proportion, up to 40 percent. In addition to hormone-related paraneoplastic syndromes, the increased formation of antibodies against cancer cells can also lead to autoimmune-like diseases if these simultaneously attack healthy body cells as part of a cross-reaction. In this context, the prognosis of tumors with antibody-related paraneoplastic syndromes is more favorable than tumors without accompanying symptoms, since in the former there is a stronger immune reaction against the cancer cells. Some tumors secrete inflammatory factors such as prostaglandins. This can cause skin changes, rheumatic complaints or gastrointestinal disorders, among other things. Special paraneoplastic syndromes affect the nervous system. In these cases, autoantibodies attack nerve cells and cause neurological symptoms. Furthermore, certain tumors also produce substances that lead to hematological changes. Overall, a variety of different paraneoplastic syndromes can thus develop.
Symptoms, complaints, and signs
Paraneoplastic syndromes are manifested by general as well as specific symptoms. Many cancers are accompanied by a general symptom complex of cachexia, increased warmth, sweating, thrombosis, leukocytosis, or anemia. Cachexia manifests itself in constant emaciation, although sufficient calories are consumed. In cancer cells there is an increased activity of mitochondria, which leads to a very high energy consumption. Metabolism is greatly accelerated, heat production is increased and fat burning is stimulated. Thus, the emaciation in cachexia is not the result of food deficiency, but of increased energy consumption. Specific symptoms include hormone-related disorders. For example, certain forms of the so-called Cushing’s syndrome occur in bronchial, hepatocellular or renal carcinomas. The increased release of ACTH stimulates the adrenal cortex to release more cortisol. This leads to truncal obesity with bull neck and moon face, as well as weakening of the immune system with increased susceptibility to infection. In an insuloma, too much insulin is produced. The blood sugar level drops dramatically.Other hormones that can be increased by carcinomas are parathyroid hormone (PTH), vasopressin (ADH), thyrotropin (TSH), calcitonin or serotonin. Calcitonin lowers the level of calcium in the blood. Increased calcium levels are caused by parathyroid hormone. Increased serotonin concentrations cause, among other things, persistent diarrhea and abdominal pain because intestinal peristalsis is constantly stimulated. TSH, in turn, stimulates the formation of thyroid hormones in the thyroid gland, causing the typical symptoms of hyperthyroidism. Antibody-mediated reactions can lead to autoimmune diseases. This can lead to rheumatic joint inflammation, inflammatory processes in the gastrointestinal tract or neurological deficits. When the skin is involved, the main symptom is excruciating itching. Furthermore, skin lesions, keratoses, or increased growth of body hair are observed.
Diagnosis and course of the disease
Depending on the symptom complex, hormone tests or tests for antibodies may provide information about the cause of certain symptoms. Imaging techniques may reveal the underlying tumor.
Complications
In most cases, this syndrome results in various complications and discomforts that occur primarily during cancer. The complaints themselves are very different and can vary greatly among themselves. As a rule, no general prediction can be made about the further course of the disease for this reason. The affected persons themselves suffer from strong sweating and also from thrombosis. Likewise, anemia and thus bleeding or fatigue and exhaustion of the patient occur. The metabolism of those affected is also affected by this syndrome, so that in most cases the patients also lose weight. The immune system is significantly weakened by the tumor disease, so that infections or inflammations occur more often, which have a very negative effect on the quality of life of the affected person. Itching or lesions on the skin may also occur. The treatment of this syndrome is carried out by treating the tumor. It is not possible to predict whether this will be successful. It is also possible that the tumor will reduce the patient’s life expectancy.
When should you go to the doctor?
Paraneoplastic syndrome occurs only in people who have cancer. Therefore, a visit to the doctor should be made at the first irregularities as well as indications of health impairment. Affected individuals suffer from symptoms such as diarrhea, an internal weakness, as well as a general feeling of illness. In case of weight loss or sweating, a doctor should be consulted. If the affected person suffers from warmth, disturbances of the blood circulation as well as a general feeling of indisposition, a visit to the doctor is advisable. Changes in the appearance of the skin, a decrease in physical performance and an increased need for sleep should be examined and treated by a doctor. Disturbances of the digestive tract, rheumatic complaints, an increased susceptibility to infections as well as a repeated fungal infection or an infestation of other germs indicate a disease. A physician should be informed of the observations and a follow-up visit should be made. Disorders of the hormonal system, changes in libido or emotional abnormalities should be discussed with a physician. A depressed mood, peculiarities of behavior as well as changes in personality are to be understood as warning signs of the organism. A visit to the doctor is advisable so that an investigation of the causes can be initiated. In addition, regular participation in preventive medical examinations offered is generally recommended in adulthood. In an early detection, first changes or abnormalities of health can be documented.
Treatment and therapy
Causally, paraneoplastic syndromes can be treated by removing the tumor. This usually causes the symptoms to disappear as well. This is especially true for endocrine-related paraneoplastic syndromes. However, there are also cases where antibody activity nevertheless remains high after tumor removal. Of course, the individual concomitant tumor diseases can be treated separately. In this regard, drug therapies or immunosuppression therapies have proven effective for antibody-related paraneoplastic syndromes. Each paraneoplastic syndrome requires its own therapeutic approach.However, causative tumor treatment should be sought whenever possible.
Prospect and prognosis
A paraneoplastic syndrome is not an isolated case, as there are several corresponding syndromes. These are considered by physicians to be complications of a wide variety of tumor diseases. However, paraneoplastic syndromes are not caused by the tumor itself or directly by its metastases. Nor are tumor-related, vascular, metabolic, infectious, or treatment-related effects involved in the development of a paraneoplastic syndrome. However, a paraneoplastic syndrome can occur without an identifiable tumor. In this case, it is standard practice to regularly screen for a tumor over a period of two to four years. It has already been proven that the paraneoplastic syndrome occurs in many cases in connection with a new tumor formation. Idiopathic syndromes must be distinguished from true paraneoplastic syndromes. Already the diagnosis of such syndromes proves to be very complex and difficult. Treatment is also difficult. However, it is by no means impossible. Instead of conventional tumor therapy, immunosuppressants are usually used – but only if no tumor could be found. Symptomatic therapies such as pain therapy or other measures are also possible. What is certain is that the type of paraneoplastic syndrome can be used to determine what kind of tumor it might be. If this can be detected early by regular scanning, and surgically removed, the prognosis improves.
Prevention
There is no general recommendation for prevention of paraneoplastic syndrome because it always accompanies a specific tumor disease. However, the focus of prevention is on the tumors. For example, the risk of developing bronchial cancer can be reduced by maintaining a healthy lifestyle and abstaining from smoking.
Follow-up
Paraneoplastic syndrome is related to cancer. The effects are not directly attributable to the tumor and are likely due to an immune response or hormonal alteration. Thus, the follow-up of paraneoplastic syndrome is consequently related to and merges with the follow-up of the actual cancer. Depending on the cause, even after tumor removal it is not necessarily given that the paraneoplastic syndrome will disappear by itself. In particular, the body’s reactions persist if the cause of the disease is antibodies that also attack healthy tissue in the body. In the follow-up, the specialist, in this case an oncologist, will take care of the symptoms of the syndrome and treat them during appropriate check-ups. Since the symptoms of the paraneoplastic syndrome are of a varied nature, one cannot assume a uniform aftercare here. The resolution of symptoms also varies greatly from individual to individual and is linked to the causative cancer and, accordingly, to the trigger of the paraneoplastic syndrome. It is not possible to make a blanket statement as to whether medications or other aids are necessary in the follow-up. The oncologist can advise patients on an individual basis. Follow-up appointments should be conscientiously kept.
Here’s what you can do yourself
Because paraneoplastic syndrome is often a parallel disease to a malignant tumor, this tumor must be detected and treated if it has not already been. Otherwise, paraneoplastic syndrome presents with different symptoms, which should be approached accordingly on an individual basis. A major focus here is on nutrition, as patients can develop life-threatening cachexia. In this case, the cancer cells consume so many calories that the patient is no longer able to consume sufficient nutrients even with a normal diet. This results in tumor-induced weight loss. In this case, high-calorie but healthy foods are advised, such as avocados, bananas or peanut butter as a spread. The immune system is also weakened by the paraneoplastic syndrome. Patients who want to do something for themselves are therefore advised to do everything that strengthens the immune system: this includes sufficient sleep as well as a healthy diet with fresh, high-fiber food, but little sugar and fat. Probiotics that enrich the intestinal flora are also recommended.Of course, patients should also not smoke or drink alcohol so as not to put unnecessary strain on the organism. Studies show that sport can be as important as medication. Even short walks in the fresh air activate the immune system, regulate the metabolism and thus ensure a better quality of life.
