There’s a lot of talk about immunotherapy in the cancer world today, and for good reason. In some cases, these treatments are approaching cures. But as someone with cancer, you may concerned about how your treatment will impact your ability to have children. Here’s what you need to know about immunotherapy and fertility.
First, What Exactly Is Immunotherapy?
The American Cancer Society (ACS) defines immunotherapy as any medication that uses the patient’s own immune system to help it fight cancer cells. This can be done by boosting the body’s own natural defenses or training the system to recognize and attack specific cells.
Why Doesn’t the Body Kill Cancer Cells on Its Own?
The immune system targets and attacks germs and foreign substances in the body, and, yes, this should include cancer cells. However, many cancer cells are altered versions of native cells that do belong in the body so the immune system does not always recognize them. Furthermore, cancer cells often multiply so rapidly that it is difficult to stop them.
What Are the Types of Immunotherapy?
There are four main types of immunotherapies.
- Checkpoint inhibitors: These work by removing the brakes from the immune system’s T cells so they are more able to recognize and kill cancer cells.
Adoptive cell transfer: CAR T-cell therapy is a type of adoptive cell transfer. In this case, T cells are removed from the patient. The ones that are most effective in fighting the tumor are selected and large batches of these T cells are grown in the lab and re-injected into the patient’s body.
Monoclonal antibodies: These are lab-made proteins that attach to specific targets on cancer cells to make them easier for the immune system to see and destroy.
Treatment vaccines: Some treatment vaccines can also fight cancer by boosting the immune system’s response to cancer cells.
How Do These Medications Impact Fertility?
Most of these immunotherapies are so new that we don’t have any long-term data on how they affect fertility. But the results so far are promising.
Catherine Diefenbach, M.D., a hematologist, oncologist, and translational physician, translational director of hematology, and the clinical director of lymphoma at the Perlmutter Cancer Center at NYU Langone Health, says doctors are cautiously optimistic that immunotherapies like checkpoint inhibitors don’t appear to have a significant impact on the reproductive system.
“I think there's still a lot that we need to know about subtle changes in fertility that may be impacted by checkpoint inhibitor therapy,” Diefenbach tells HealthCentral. “But I think the big picture is they're much safer and a huge improvement over chemotherapies which were cytotoxic and much more toxic to fertility.”
Aimee Talleur, M.D., a physician in the department of bone marrow transplant and cellular therapy at St. Jude Children’s Research Hospital, also emphasizes the importance of thinking about other medications given at the time of treatment when looking at fertility issues.
“A lot of patients are going to be heavily pretreated,” Talleur says. “Or they will be beginning chemotherapy or something else in conjunction with immune therapy. So even if the immune therapy itself does not increase the patient’s risk for fertility issues, they might be getting something else at the same time that does.”
Often the patients Talleur sees have relapsed or had a recurrence of cancer, she says. As a result, they’ve already received standard chemotherapy and radiation that put them at risk for problems with conception.
“Since we're seeing patients late in the game, we're trying to increase our use of our fertility colleagues to have patients at the appropriate age be evaluated because even though they've been exposed to things in the past that doesn't mean infertility is a guarantee,” Talleur says.
Looking toward the future, Talleur says there may be a time when some immunotherapies are given without chemotherapy as a first-line treatment. Some of those medications could target the reproductive system.
“When you have a targeted therapy, you’re picking a target that is on a cell,” Talleur says. For example, she explains, the FDA-approved CD19 CAR therapy is looking for the CD19 target on the surface of the tumor cell.
“Tumor cells have these markers, but normal cells have things on their surface too,” she says. “When researchers are finding targets, they need to think about not only which tumor cells have that target, but also is there a normal tissue in the body that also has that same target? The reproductive organs do not have CD19, but as we’re trying to expand the targets we can look at, this is something we need to be aware of.”
The Bottom Line
If you’ve been diagnosed with cancer, talk to your doctor about fertility preservation right away if you want to have children in the future. They can talk you through all of your options and help you choose the best therapies for you. If you choose immunotherapy, it’s likely not the first treatment you’ve tried. But the good news is that early studies shows that these therapies have little impact on fertility, and more research is on the horizon.