How long can expanders stay in?

Sorry to hear that you decided not to pursue the next stage of your reconstruction. It's hard to say how long they last, but the typical working life is less than 18 months. If you were fully expanded, an exchange to a permanent implant will likely give you a more natural looking and feeling reconstruction. If you have spite and anger toward a certain doctor, perhaps make a relationship with a new doctor during this process. Best wishes.

The longest I have seen someone keep an expander in is 5 years, but I've heard of people keeping them for longer than this. As long as they are not infected or causing pain, even a ruptured tissue expander can, in theory, stay in the body. The main question would be why not just have them removed, but I supposed I understand if someone would never want to undergo any further surgery in life after what happened that lead to the placement of the expanders in the first place. The only other thing I would caution against is if you ever need an MRI, it is not advised to have one with expanders in place as they often have a metallic port. 

Tissue Expanders are temporary devises.  They do, however, have a considerable lifespan.  In fact, I have recently exchanged a patient who had a TE in for a decade.  I am not recommending that you wait for an extended period of time, but it is a reminder that this technology is well built. I am sorry that you are having a bad time with your reconstruction.  But...sometimes a "holiday" from surgery is a good idea.  If your TE's are relatively expanded, you do not need to rush into your next stage.  Time may give you a fresher perspective on the process.  I am sure that you are being managed by a very competent surgeon, but it isn't insulting or unfair to ask for another opinion.  If your TE are not expanded much, the folds native to the plastic can become the sites of an implant shell tear. This will collapse the TE.  I do hope you feel better about the process soon.