Small-cell lung cancer is a fast-growing cancer of the lung that spreads quickly. Most cases of SCLC are caused by smoking. SCLC often starts in the breathing tubes in the center of the chest, then rapidly spreads to other parts of the body (such as the brain, liver and bones) before causing any symptoms. SCLC symptoms may not differ considerably from the symptoms of non-small cell lung cancer (NSCLC); however, SCLC may be more likely to cause different complications.
General Symptoms
According to the National Institutes of Health, general symptoms of small-cell lung cancer (SCLC) include cough, bloody phlegm, chest pain, shortness of breath, loss of appetite, weight loss and wheezing. In some cases, fever, difficulty swallowing, hoarseness, facial swelling or weakness may occur.
Paraneoplastic Syndromes
Small-cell lung cancer can sometimes cause one or more complications with the nervous system that are generally referred to as paraneoplastic syndromes. Paraneoplastic syndromes are rare, occurring in fewer than 1 percent of people with cancer, and may appear in the early stages of cancer before a person knows he has it. Symptoms associated with neurological paraneoplastic syndromes include problems with walking, loss of muscle tone and fine motor coordination, memory loss, difficulty swallowing, slurred speech, vision problems, sensation changes, numbness or tingling in the arms and legs, dizziness, dementia and seizures.
One paraneoplastic syndrome associated with SCLC is called Lambert-Eaton syndrome. This syndrome causes the muscles of the hips to become weak, making it difficult to get up from a sitting position. It can progress, causing the muscles of the shoulder to become weak as well.
Cerebellar ataxia--a rare condition characterized by unexplained loss of balance and unsteady arm and leg movements--is also caused by SCLC.
Superior Vena Cava Syndrome
Small-cell lung cancer may cause superior vena cava syndrome, a set of complications that occurs when the superior vena cava (a major vein that feeds blood to the right chamber of the heart) becomes blocked. The most common symptoms include problems breathing and coughing, and swelling of the face, neck, upper body and arms. Less commonly, chest pain, problems swallowing, hoarse voice, problems talking, coughing up blood, swollen veins in the chest or neck, bluish-colored skin and drooping eyelid may occur.
