Understand your options before you decide whether adjuvant therapy is for you. Balance the side effects with the benefits of treatment when making your decision. You've already had surgery to remove your tumor. But how can you be sure that some cancer cells haven't remained behind in other parts of your body? Your doctor might suggest something called "adjuvant therapy" as a way to kill any remaining cancer cells that are too small to be seen by available tests. Adjuvant therapy is used after primary treatments, such as surgery or radiation, to decrease the chance that your cancer will recur. But the added benefit of adjuvant therapy doesn't come without a price — the side effects can be more than minor inconveniences.