Can a lung scar caused by pulmonary tuberculosis (already treated) ever disappear? It's been 2 years and the scar is still there every xray exam.

Tuberculous scar. Tuberculous scars disappearing ! a scar is a scar it wont disappear. If anything it may predispose you to lung cancer, and there is nothing that could predict conversion to malignancy.
Unlikely. The scarring will most likely be permanent, however the good news is that other than the xray change it should be asymptomatic. Hope this helps.