Cancer of Unknown Primary

Cancers of unknown primary refer to cancer with an unclear origin and are grouped according to the type of cancer cell. Squamous cell cancers, found in the skin and linings of certain organs, are the most common. Around 31,000 cases of cancer of unknown primary are diagnosed in the United States each year. The five-year survival rates for cancers of unknown primary vary. Because of its nature, risk factors are difficult to assess. Autopsies show that many cancers of unknown primary start in the pancreas, lungs, kidneys, throat, larynx, or esophagus – organs that are susceptible to smoking. Cancers of unknown origin that begin in the stomach, colon, or rectum point to diet and obesity as risk factors. Symptoms of cancer of unknown primary include swollen lymph nodes, lingering pain, change in bowel or bladder habits, fever or night sweats, unexplained weight loss, and persistent cough. Treatments include surgery, chemotherapy, radiation, or a combination of these.