Yoga is a highly rated post-surgery cancer care technique. Every cancer survivor will choose to talk with their doctor about the best practices for their unique condition. As a trainer, your best shot lies in offering standard practices.
In that case, have a credible tech company such as Gymcatch install a fitness instructor software to save time and train as many clients as you can. Although the fight against cancer is not easy, your clients must understand that giving up can never be an option.