In up to 25% of people who get lung cancer, there are no apparent symptoms at the time of diagnosis. In others, symptoms can occur from the cancer itself, from the metastatic spread of the cancer beyond its origin in the lung, or from so-called paraneoplastic syndromes that result from the production of hormone-like substances by the lung cancer cells. Common symptoms include cough, shortness of breath, wheezing, chest pain, and coughing up blood. Other symptoms can include shoulder pain, hoarseness, or difficulty swallowing. Symptoms of metastatic disease can include headaches, vision changes, seizures, weakness, or symptoms of stroke. Symptoms common to many cancers include fatigue, unexpected weight loss, and depression.