Just weeks after receiving treatment for pancreatic cancer, 86-year-old Supreme Court Justice Ruth Bader Ginsburg has been back in action, appearing on stage to receive an honorary degree at the University at Buffalo last week, then flying to Little Rock, Ark. for a charity event earlier this week.
“I am pleased to say that I am feeling very good tonight,” Justice Ginsburg told reporters, likely causing people with pancreatic cancer to wonder, “Could I benefit from this treatment that has RBG feeling so great, too?”Read More
What is This More Precise Radiation Therapy, and How is it Different?
“SBRT,” the type of radiation therapy that Justice Ginsburg received—and the type of radiation that the ASTRO guidelines address in pancreatic cancer for the first time—can administer very high doses of radiation to a precise location in the body. The way this works is through a number of separate high-intensity beams of radiation targeting a tumor from different angles.
“It’s a very focused form of radiation that’s used to treat small tumors… that have not spread to nearby lymph nodes or other parts of the body,” Dr. Billy Loo, an associate professor of Radiation Oncology at Stanford University’s Stanford Cancer Institute, explained to SurvivorNet in a previous conversation. Dr. Loo spoke about this therapy in the context of treatment for early-stage lung cancer, but according to Dr. Diane Simeone, director of pancreatic cancer at NYU Langone’s Perlmutter Cancer Center, the treatment is occasionally used for patients with pancreatic cancer, too.
“It is not typically used as a front-line treatment,” Dr. Simeone told SurvivorNet (front-line meaning the first treatment used), “which would be surgery or combination chemotherapy. But there may be other mitigating factors that have determined why radiation alone is being used as the treatment in this setting.”
Dr. Simeone went on to explain these “mitigating factors” that might make stereotactic ablative radiotherapy a good choice for someone with a tumor on their pancreas. “[It] can be used if other treatment options have failed (like chemotherapy) or if surgery is not a good option due to tumor issues involving other key structures, like critical blood vessels.” Surgery may not always be the best option for elderly patients either, Dr. Simeone explained.
The new ASTRO guidelines mirror what Dr. Simeone told SurvivorNet – that SBRT is an option when surgery is not.
“For patients with locally advanced disease (who are not candidates for surgery), systemic chemotherapy followed by either chemoradiation or SBRT is recommended conditionally as an option for definitive treatment,” according to the guideline.
If, on the other hand, surgery is an option—and the patient has already had it—the guideline states that “SBRT is recommended only if the patient is enrolled in a clinical trial.”
Recommendations on Side Effects
In addition to the recommendations on when to treat pancreatic cancer with SBRT, the new ASTRO guidelines included information on dosing and reducing side effects.
When treating pancreatic cancer with radiation (be it standard radiation or SBRT), for instance, the guideline recommends giving patients prophylactic anti-nausea medicines, and occasionally antacids or acid-reducing medicines.
“If we know that certain side effects tend to occur with a relatively modest or high frequency – such as nausea and stomach pain – there are medications we can give to patients prior to treatment to help mitigate those side effects,” explained Dr. Manisha Palta, a radiation oncologist at Duke University who co-chaired the group that wrote the guidelines.
“With Improvements In Distant Disease Control, Local Control Becomes Increasingly Important
Pancreatic cancer—which causes an estimated 45,570 cancer deaths annually—is a particularly difficult cancer to treat, in part because it is usually (more than half the time) diagnosed at an advanced stage, after it has already spread beyond the pancreas.
Once pancreatic cancer has spread widely throughout the body, actually treating the tumors with radiation becomes more difficult; instead, at the metastatic stage, radiation is usually used for palliative purposes—meaning to reduce any pain or complications that the cancer is causing. Indeed, the new ASTRO guideline recommends that “for selected patients with metastatic pancreatic cancer, palliative radiation therapy to either the primary or select metastatic sites for symptom management is recommended.”
Dr. Allyson Ocean, a medical oncologist at Weill Cornell Medicine and NewYork-Presbyterian, previously explained to SurvivorNet that this has to do with a protective layer of tissue surrounding pancreatic cancer tumors called a “stromal tissue.”
“The cancer cells are surrounded by what is called a stroma, and the stroma serves as a barrier for medications to get into the cancer to kill it,” Dr. Ocean said “Stroma is tissue that surrounds the cancer tumor. “So chemotherapies have a hard time getting in, radiation has a hard time penetrating. Think of pancreatic cancer as an oatmeal raisin cookie and the raisins are actually the cancer cells, and the cookie part is actually all the stroma around it. And imagine having to navigate through all that stroma for a treatment to be able to get into a cell to kill it. So that’s why the treatments just really aren’t good enough to penetrate the cancer. But we’re improving, we’re getting better treatments.”
Treatments are indeed getting better. According to Dr. Palta, “In the past several years, newer systemic therapies are proving to be more effective at controlling this cancer when it spreads, and fewer people are dying from distant disease. This makes treatments like radiation to manage local disease more meaningful.”