For locally advanced and metastatic pancreatic adenocarcinomas, which together represent over 80% of cases, numerous trials comparing chemotherapy regimes have shown increased survival times, but not to more than one year. Overall five-year survival for pancreatic cancer in the US has improved from 2% in cases diagnosed in 1975–1977, and 4% in 1987–1989 diagnoses, to 6% in 2003–2009. In the less than 20% of cases of pancreatic adenocarcinoma with a diagnosis of a localized and small cancerous growth (less than 2 cm in Stage T1), about 20% of Americans survive to five years.