Seeing as we're doing some medical guess work - there could be another somewhat more worrying explanation of Job's weightloss other than his 'whipple procedure'. Jobs never had ordinary pancreatic cancer of the exocrine pancreas (which would have killed him quick quick) - he had a rarer less malignant form of pancreatic cancer (neuroendocrine islet cell cancer) which is a cancer of the endocrine pancreatic cells (the ones that make hormones like insulin and glucagon - does that word sound familiar - HORMONE!). So my guess is that he has a recurrence of a a glucagonoma - ie the cells that make the hormone glucagon have gone cancerous and are making way too much. Glucagon raises you blood sugar by promoting a whole variety of catabolic processes - hence the bad ass weight loss. Just my medical 2 cents worth.

http://en.wikipedia.org/wiki/Glucagonoma