The goal of the Whipple procedure (pancreatoduodenectomy) is to remove the head of the pancreas, where most tumors occur. Because the pancreas is so integrated with other organs, the surgeon must also remove the first part of small intestine (duodenum), the gallbladder, the end of the common bile duct and sometimes a portion of the stomach. In the reconstruction phase of the operation, the intestine, bile duct and remaining portion of the pancreas are reconnected. -- Mayo Clinic
It results in a cure for some but not all. Certainly more. Yes, one of the ways to extend the median lifespan for the overall patient pancreatic cancer population is to get their cancer back to an operable stage. Pegph20 with Gem and perhaps with Gem/Abraxane will do this for many.
This is why I have said that I think the survival results on the 30th may be better than expected. The drug makes surgery an option in many who were otherwise diagnosed too late.
Mayo also points out that while the Whipple procedure increases survival, "The Whipple procedure is a difficult and demanding operation for both the person undergoing surgery and the surgeon."