Cancer
![](/Images/godic/202501/02/Tumor_Mesothelioma2_legend5143.jpg")
![Symptoms of cancer metastasis depend on the location of the tumor.](/Images/godic/202501/02/Symptoms_of_cancer_metastasis.svg5143.png")
![The incidence of lung cancer is highly correlated with smoking.](/Images/godic/202501/02/Cancer_smoking_lung_cancer_correlation_from_NIH.svg5143.png")
![Cancers are caused by a series of mutations. Each mutation alters the behavior of the cell somewhat.](/Images/godic/202501/02/Cancer_requires_multiple_mutations_from_NIHen5143.png")
Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. Not all tumors are cancerous; benign tumors do not spread to other parts of the body. Possible signs and symptoms include a lump, abnormal bleeding, prolonged cough, unexplained weight loss and a change in bowel movements. While these symptoms may indicate cancer, they may have other causes. Over 100 cancers affect humans.