There are many causes of hives or, in medical terms, urticaria. Though cancer is by no means a major cause of the condition, there is a connection between some cases of hives and cancer, particularly gastrointestinal, lung, and lymphoma. Hives may be a precursor to cancer, in some cases, and chronic conditions should be checked. They usually co-exist with other symptoms, such as weight loss, night sweats, abdominal pain, and coughing.
Hives are red welts that may be small and localized on the body or large and widespread. They are typically not associated with long-term or serious complications, but instead, they are caused when there is an allergic reaction and the body releases histamine and other chemicals. This is usually in response to certain foods, medications, extreme or sudden changes in temperature, and insect bites, among other factors. The mechanism causing the reaction can be allergic or non-allergic.
The majority of cases of hives are acute, meaning that they last less than six weeks. Most of these are caused by an allergic reaction to a specific substance. Chronic hives, or cases lasting more than six weeks, occur in about 30% of cases. This is when the condition may be a symptom of an underlying disease such as thyroid disease; hepatitis; viral, fungal or bacterial infections; or cancer.
When hives are accompanied by other cancer symptoms, such as weight loss, night sweats, abdominal pain, hemoptysis, jaundice, coughing, or lymphadenopathy, then tests need to be carried out to find the cause. The combination of these symptoms and hives may be a cause for alarm, but other conditions need to be ruled out first before the underlying etiology for both conditions can be determined.
The diagnostic approach depends on the suspected type of cancer. The most common kinds that hives may be a precursor of are gastrointestinal, lung, and lymphoma. Gastrointestinal cancer includes cancer of the esophagus, stomach, liver, pancreas, bowel, biliary system, and anus. Lymphoma is cancer of the lymphatic system, including the lymph nodes and bone marrow.
An allergist-immunologist should be consulted in cases of chronic hives. In order to check whether there is a connection between hives and cancer in individual cases, a detailed medical history of the patient and the patient's family needs to be taken. Details of the home and work environment may be important, and tests may include blood and urine tests and X-rays. If a food allergy is suspected but not obvious, then a skin biopsy many be necessary. The link between this symptom and cancer is a very small one, but in the presence of other symptoms, it is a connection that needs to be checked.