Every cancer has distinct risk factors, or causes. It is difficult to identify specific causes of CUP since the exact type of cancer is unknown.
The symptoms of carcinoma of unknown primary are organ-specific. These symptoms may include:
Lymphadenopathy, a condition in which the lymph nodes are swollen, firm to the touch, but do not hurt. Cancers frequently spread to the lymph nodes.
A mass in the abdomen or a feeling of abdominal fullness. This is often caused by a cancer growing in the liver or the spleen, or by a collection of fluid inside the abdomen called ascites.
Shortness of breath. This symptom may be caused by cancer that has spread to the lungs or from pleural effusion, a build-up of fluid and cancer cells in the area around the lungs.
Pain in the chest or abdomen. Cancer growth around nerves or tumors pressing against internal organs may cause these symptoms.
Bone pain. Severe pain may occur when cancer has spread to the bones. Bones that are made weak by the cancer's spread may contribute to fractures. These fractures may result from minor injuries, or even from normal activities, like rolling over in bed.
Skin tumors. Some cancers start out in organs and spread through the bloodstream to the skin. Skin metastases are sometimes the first sign of spread from a cancer of unknown primary.
Weakness, fatigue, poor appetite, and weight loss. These generalized symptoms may happen because the cancer has spread to specific organs or systems. Also, some cancers release hormone-like substances into the bloodstream that affect metabolism and cause these same problems.
Deanna Swartout-Corbeil R.N., The Gale Group Inc., Gale, Detroit,