While there's no one way to guarantee you won't get cancer, there are many ways to lower your risk. For instance, you can quit drinking alcohol, reduce your weight through healthy diet and exercise, or take measures to prevent contracting HPV—all of which can help you avoid a cancer diagnosis. On top of these changes, doctors say one more intervention is essential in order to help ward off a uniquely deadly—but rarely discussed—form of cancer. Read on to learn which one risk factor links more than half of people with this dangerous cancer, and why changing your habits could save your life.
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CUP cancer occurs when the origin of the disease is not known.
Cancer of unknown primary, also known as carcinoma of unknown primary or CUP cancer, occurs when doctors cannot identify where a cancer has originated. When this happens, the cancer has already metastasized by the time of diagnosis, but the primary tumor has not been found.
This can happen for several reasons, experts explain. Sometimes the original cancer is not found because it is too small to be seen on scans. Other times, the original cancer has been fought off by the body's immune system or removed during surgery for another condition, says the Mayo Clinic.
CUP is considered an especially dangerous diagnosis.
A CUP cancer diagnosis is especially dangerous because cancer treatments work by targeting specific cancer types. Without knowing where the cancer cells first formed, cancer cells often respond less effectively to treatment.
"If carcinoma of unknown primary is found, doctors work to try to identify the primary tumor site," the Mayo Clinic explains. "Your doctor might consider your risk factors, symptoms, and results from exams, imaging tests and pathology tests when trying to determine where your cancer began."
This particular type of cancer is often deadly. According to Cancer Research UK, there is only a 16 percent survival rate one year following diagnosis.
Half of people with CUP cancer have this in common.
Experts say roughly half of all patients diagnosed with CUP have one crucial risk factor in common: they have a history of smoking. Though many people primarily associate smoking with lung cancer—and it is true that 90 percent of lung cancer cases are linked with cigarette smoking—this unhealthy habit can also cause cancer in just about every part of the body, the CDC explains.
"Smoking is probably an important risk factor for CUP. More than half of patients with CUP have a history of smoking," explains the American Cancer Society. "When autopsy studies are done, many cancers of unknown primary are found to have started in the pancreas, lungs, kidneys, throat, larynx, or esophagus. Smoking increases the risk for all of these cancers," their experts warn.
Jeffrey Dlott, MD, Senior Medical Director for QuestDirect explains why cigarettes can wreak so much havoc on your health. "Cigarettes contain literally thousands of chemicals, and dozens of them are known carcinogens, or harmful toxins known to cause cancer," Dlott told Best Life, explaining that poisons in tobacco smoke can cause damage to or even change a cell's DNA, leading to out-of-control cell growth and the creation of cancerous tumors. "Toxins in cigarette smoke also weaken the body's immune system, meaning it is harder to kill cancer cells once they form in the body," he added.
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Look out for these symptoms of CUP cancer.
CUP cancer is not a single disease, but instead represents a range of possible diseases with many possible symptoms. However, experts say that there are some symptoms that are considered more common among CUP cancer patients. These can include persistent pain, a lump under the skin, bowel changes, coughing, frequent urination, fever, night sweats, or weight loss.
In fact, anything persistent and out of the ordinary is worth mentioning to your doctor. "Preventive care is extremely important because those routine checkups can identify potential health problems early on before they have a chance to get worse," says Dlott. "I cannot stress enough that people need to get back into the routine of getting annual screenings that they may have put off due to the pandemic."
Dlott adds that it's important for people to "keep a close watch on what is going on with their own bodies. If something feels off or if something is bothering them, they shouldn't wait to get it checked out," he told Best Life. Schedule an appointment with your if you've noticed anything abnormal lately, or if you've let your checkups lapse during the pandemic.
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