Not all countries require a medical for a study permit plus you still need to be aware of medical coverage as well given insurers unfortunately still exclude any possible cancer history related coverage so you might need as well to check with a college you have in mind given colleges often support students with medical insurance.
http://www.cic.gc.ca/english/helpcentre/answer.asp?qnum=489&top=15
Other than that here’s hoping your remission is long and uneventful regardless how the study permit goes.