When the War on Cancer was declared in the early 1970s, the average five-year relative survival rate for all cancers was only 50 percent. Due to advances in research over these last decades, mostly funded by the National Institute of Health and National Cancer Institute, we've seen an increase in the five-year survival rate now being 68%. However, there are a number of cancers that still fall below 50 percent survival. These cancers are considered the "deadliest," cancers. Sometimes symptoms that we ignore can overlap with potential signs of cancer.