They ate two completely different procedures and BMI, Metabolic Disorders need to be consider as well as at the very least a fluoroscopy needs to be preformed. I recommend a couple of tests before making a decision. One thing is clear you do need to have a procedure done before you weight gets out of control.
A lap-band needs to be closely supervised, when we started working with obesity and lap-bands 20 years ego there where very few bariatric options, today we know that an unsupervised lap-band can create very serious damage than can include erosion and perforation of the stomach. You need to get tested asap
Regain after a 10 year R-Y can be due yo pouch enlargement however I recommend a GI scan to determine if the restrictive function has being compromise or the anastomosis is not in the right place to do its malabsorption job. Definitely testing is needed before a revision is considered.
You will definitely have to speak to your oncologist, my opinion is not to have it ajustes as you might experience nausea.
It’s very likely that your stomach has regain volume due to many posible factors, a revision procedure is very likely to be needed however it is important to do a full assessment. The only fact that I’m sure is that you have viable options that will require dietary and behavioral modifications to obtain long term results