"The two different types have fairly dramatically different clinical behaviors, " said Matthew Kulke, director of the carcinoid and pancreaticneuroendocrinetumor program at the Harvard-affiliated Dana-Farber Cancer Institute in Boston.
But Mr. Jobs had what is called a neuroendocrinepancreatictumor, a type that accounts for fewer than 5% of pancreatic cancers and, experts say, differs substantially from the more common kind.
Statistics for pancreaticneuroendocrine tumors, a rare tumor type that is not as aggressive as standard pancreatic cancer, are murkier and less reliable given how few patients there are.