It basically means removing most of the organs in your upper abdomen, including the main tumor, then 'replumbing'; everything.

Pain in the upper abdomen which can spread to the back.

My liver and stomach are bloated, my skin taut across the upper abdomen, like in pregnancy except in the wrong place and with no life-affirming kicks.

It will refer pain often to the mid upper abdomen.

This body type enlarges the arms, chest, hips, and rear before other parts, such as the waist and upper abdomen.