Originally defined as systemic therapy given before local treatment, neoadjuvant therapy is the administration of therapeutic agents such as chemotherapy, radiation therapy, hormone therapy before the main treatment or primary interventions, often surgery, for cancer.
The goal of neoadjuvant therapy is to improve the success rate of the main treatment. This can generally be achieved by: shrinking tumors before surgery, making them easier to remove and possibly allowing for less invasive surgical procedures; targeting micrometastases early, potentially improving long-term survival; and/or assessing the cancer's response to specific drugs, helping guide future treatment decisions. While neoadjuvant therapy offers several benefits, it may also have potential drawbacks, including increased toxicity, treatment costs, and the possibility of delaying effective treatment in some cases.
Neoadjuvant therapy differs from adjuvant therapy, which is given after the primary treatment to reduce the risk of cancer recurrence. Both approaches aim to improve overall treatment outcomes, but the timing of administration distinguishes them. Chemo before operating, or operating before chemo, that is the question.
It is commonly used in various cancer types, including breast, lung, and colorectal cancers, and has become standard practice for certain conditions, such as osteogenic sarcoma, where it facilitates limb-sparing surgery.