July/August 2025
Before & After
What is neoadjuvant immunotherapy?
For many cancer patients, successfully removing their tumor is often just the first step. They will also be referred to a medical oncologist to discuss further treatment, such as immunotherapy (which helps the immune system identify and destroy hidden cancer cells) or chemotherapy (which kills fast-growing cancer cells, but can also affect healthy cells)."
Why? Even after successful surgery, there's a risk of microscopic cancer cells being left behind or having spread locally. Medical oncology targets these cells to significantly reduce the chance of cancer returning.
But recently, for certain types of cancers, physicians have discovered an advantage in administering immunotherapy before surgery. This is called neoadjuvant (“neo” meaning new or preceding, “adjuvant” meaning helpful or assisting) immunotherapy.
“For some cancer types, neoadjuvant immunotherapy can make a tumor smaller and easier to remove surgically,” explains medical oncologist Michael Chahin, DO, of Summit Cancer Care. “It can also target cancer cells that may have spread from the tumor to other parts of the body, helping to prevent recurrence.”
The Right Response
Traditionally, the procedure for many cancers involved surgery to remove the primary tumor, followed by adjuvant chemotherapy, radiation or immunotherapy. However, the use of neoadjuvant immunotherapy has grown significantly in recent years. Besides potentially easing the burden of surgery, this approach also allows physicians to observe how the tumor responds in real time.
“We're looking for something called pathologic response,” Dr. Chahin says. “For example, when your surgeon goes in to remove the cancer, we may see there's a lot less of it than we thought there was before.”
Melanoma, non-small cell lung cancer, and certain cases of breast cancer have shown the most beneficial pathological responses so far. Neoadjuvant immunotherapy is also being actively investigated for other cancer types, including colorectal, esophageal, and bladder cancer.
“I think this approach will be incorporated into more treatments in the coming years, as more and more studies are done,” Dr. Chahin says.
Collaboration on the best possible treatment plans for patients, including discussions about neoadjuvant immunotherapy, happens weekly at the Nancy N. and J.C. Lewis Cancer & Research Pavilion (LCRP).
“We have great collaboration through our multi-disciplinary tumor boards at the LCRP,” Dr. Chahin says. “Medical oncology, surgery, radiation oncology—everyone involved is able to weigh in on the best course of treatment for patients.”
Added Value
Some patients may be wary of adding another form of treatment to their plan, so Dr. Chahin discusses the potential benefits of this approach during the treatment decision process.
“To hear you have cancer is a scary thing to begin with, and then you are learning all of these new terms, and patients may wonder if having this new procedure before surgery will make their overall treatment more difficult,” Dr. Chahin says. “These are very reasonable concerns, but I think if we are able to discuss it and come to an understanding, patients will ultimately see how this can improve their outcomes, both their surgical outcome and the overall outcome.”
Patients may also worry about experiencing more side effects. While immunotherapy is often better tolerated than traditional chemotherapy, it still comes with its own unique set of side effects including rash, fatigue and gastrointestinal issues. But patients are closely monitored in order to quickly treat these common side effects.
While the idea of being overtreated is a valid concern for patients, physicians consider neoadjuvant immunotherapy primarily for those most likely to benefit, based on their cancer type and tumor characteristics. Dr. Chahin hopes the number of patients who qualify for this treatment will continue to grow.
“Neoadjuvant immunotherapy is helping us to take better care of patients and improving outcomes,” Dr. Chahin says. “It has been a very exciting development in cancer care.”