All massage therapists in Canada are taught how to treat scar tissue. Top surgery scars are physically no different from any others and should not be a stigmatized topic for therapists or clients. I consider gender affirming care to be vital to the wellbeing of humanity as a whole, and I know that most top surgery doesn’t come with a lot of information.
The massage therapy I do for top surgery includes gentle treatment of the scars and the surrounding muscles and fascia, and remedial exercise information if it wasn’t provided after your procedure. If you used a binder prior to surgery, I also treat your diaphragm and ribcage, because they are often (literally) impacted by the mechanics of binders.