What to Know About Sentinel Lymph Node Biopsies for Gynecologic Cancers: Has My Cancer Spread?
A sentinel lymph node biopsy can answer that question for some gynecologic cancers.
Oncologists have many tools available to help them determine the stage of a cancer and how to treat it. Sentinel lymph node biopsy (SLNB) is one of them. SLNB is commonly used for breast cancer and melanoma. But it can also play a pivotal role in the treatment some gynecologic cancers.
“The procedure can be very important in staging a gynecologic cancer and to help us identify if a cancer has spread. Once we know the stage and spread, we can best tailor the therapy,” explained Christina S. Chu, MD, Interim Chief of the Division of Gynecologic Oncology at Fox Chase Cancer Center.
What is the sentinel lymph node?
Lymph nodes are small organs that are part of the body’s lymphatic system. Because cancer cells often travel through the lymphatic system, lymph nodes can play an important role in determining whether cancer cells have spread to other parts of the body. “Lymph nodes are laid out in the body sequentially, almost like stops on a bus line,” Chu explained.
The sentinel lymph node is the first node to which cancer cells are most likely to spread from the main tumor site. “It’s like the first stop on the bus line,” Chu said. Conducting a biopsy of that node allows a patient’s care team to determine the likelihood that a gynecologic cancer has spread to other nodes farther away from the tumor—without having to remove and test all of those other nodes.
“If we can biopsy the sentinel node and it’s negative, the chance of other nodes being positive is very small,” Chu said. On the other hand, if cancer is found in the sentinel node, it’s more likely that it has spread to other lymph nodes as well.
Sentinel lymph node biopsy for gynecologic cancer
Sentinel lymph node biopsy is often performed for vulvar and endometrial cancer and is starting to be more widely used for cervical cancer.
“For vulvar cancers, we typically recommend a nodal assessment for tumors with more than 1 millimeter of invasion,” Chu said. “For those with endometrial cancer, we recommend anyone who’s having a hysterectomy to have an SLNB.”
The procedure may also be appropriate for patients with cervical cancer who are considering a radical hysterectomy—surgery to remove the uterus, cervix, and part of the vagina—depending on the size of the tumor as well as other factors.
Knowing whether a sentinel node is cancerous can help patients with gynecologic cancers and their care teams make better treatment decisions. For instance, SLNB can be used to determine whether a patient whose cancer has spread needs radiation—and if so, where the radiation should be directed, Chu explained.
The procedure can also help improve a patient’s quality of life. Removing just the sentinel node potentially helps a patient avoid unnecessary surgery that would be needed to remove multiple lymph nodes. It also reduces the chance that a patient will experience lymphedema, or painful tissue swelling, particularly in the pelvis and legs.
Know where to go
SLNB is a procedure that’s both low-risk and minimally invasive. But it requires surgical expertise and specialized equipment, so it should be performed at a major cancer center.
For vulvar, endometrial, or cervical cancer, a surgical oncologist specializing in gynecologic cancers is the best physician for the job, especially when SLNB is being performed at the same time as a hysterectomy, Chu noted. “This needs to be done by a specialist,” she said. “Where you start your cancer care matters.”