From the Guidelines
Neoadjuvant and adjuvant therapies differ primarily in their timing relative to the main cancer treatment, typically surgery, with neoadjuvant therapy administered before the primary treatment to shrink tumors and adjuvant therapy given after the primary treatment to eliminate any remaining microscopic cancer cells and reduce the risk of recurrence. The choice between neoadjuvant and adjuvant therapy depends on cancer type, stage, and individual patient factors, as seen in the treatment of HER2-positive early breast cancer, where neoadjuvant chemotherapy plus pertuzumab–trastuzumab is recommended for patients with high-risk disease 1. Neoadjuvant therapy allows for assessment of therapy response, which is of well-established prognostic value and may guide choice of postoperative treatment, as noted in the ESMO clinical practice guidelines for early breast cancer 1. In contrast, adjuvant therapy is given after the primary treatment to eliminate any remaining microscopic cancer cells and reduce the risk of recurrence. Both approaches may use the same treatment modalities—chemotherapy, radiation therapy, hormone therapy, immunotherapy, or targeted therapy—but their timing and goals differ. For example, locally advanced breast cancer often receives neoadjuvant chemotherapy to shrink the tumor before surgery, while early-stage colon cancer typically undergoes surgery first, followed by adjuvant chemotherapy if there are high-risk features, as discussed in the context of primary breast cancer treatment 1.
Some key points to consider when deciding between neoadjuvant and adjuvant therapy include:
- The type and stage of cancer, with neoadjuvant therapy often recommended for locally advanced or large operable cancers 1
- The potential for tumor shrinkage and improved surgical outcomes with neoadjuvant therapy 1
- The importance of assessing therapy response and guiding postoperative treatment decisions with neoadjuvant therapy 1
- The role of adjuvant therapy in eliminating remaining microscopic cancer cells and reducing the risk of recurrence 1
Ultimately, the decision between neoadjuvant and adjuvant therapy should be based on individual patient factors and the specific characteristics of the cancer, with the goal of optimizing cancer control and improving patient outcomes, as recommended by the ESMO clinical practice guidelines for early breast cancer 1.
From the Research
Difference between Neoadjuvant and Adjuvant Therapy
- Neoadjuvant therapy is given before the main treatment, which is usually surgery, to reduce the size of the tumor and make it easier to remove 2.
- Adjuvant therapy, on the other hand, is given after the main treatment to reduce the risk of the cancer coming back 3.
Purpose of Neoadjuvant and Adjuvant Therapy
- The purpose of neoadjuvant therapy is to improve the chances of a successful surgery by reducing the size of the tumor, and to assess the response of the tumor to the treatment 2.
- The purpose of adjuvant therapy is to eliminate any remaining cancer cells that may have been left behind after surgery, and to reduce the risk of recurrence 3.
Types of Neoadjuvant and Adjuvant Therapy
- Neoadjuvant therapy can include chemotherapy, radiation therapy, or a combination of both 2.
- Adjuvant therapy can also include chemotherapy, radiation therapy, hormone therapy, or targeted therapy, depending on the type of cancer and the individual patient's needs 4.
Benefits and Risks of Neoadjuvant and Adjuvant Therapy
- Neoadjuvant therapy can improve the chances of a successful surgery and reduce the risk of recurrence, but it can also increase the risk of side effects and complications 2.
- Adjuvant therapy can reduce the risk of recurrence and improve survival rates, but it can also increase the risk of side effects and complications, such as heart disease and leukemia 4, 5.
Examples of Neoadjuvant and Adjuvant Therapy
- Neoadjuvant chemotherapy with doxorubicin and docetaxel has been shown to be effective in treating locally advanced breast cancer 5.
- Adjuvant chemotherapy with anthracycline and taxane has been shown to reduce the risk of recurrence and improve survival rates in breast cancer patients 4.
- Neoadjuvant therapy with doxorubicin-cyclophosphamide followed by weekly paclitaxel has been shown to be effective in treating early breast cancer, with a complete pathologic response rate of 26.0% 6.