People with liver cancer or pancreatic cancer sometimes have tumors that are too large to be removed through surgery. Conventional radiation doses are not able to control these tumors. A new radiation approach using higher doses can control large tumors in these organs, offering patients hope for a cure or longer-term survival.
When Gary Stroud, a retired high school English teacher, began losing weight in early 2017, he at first thought it was the result of cutting carbohydrates from his diet. But the loss became so dramatic — nearly 40 pounds in about a month — that he went to get a medical workup and then a CT scan.
He was stunned to learn that he had a very large tumor in his liver that extended into the right atrium of his heart. Because of its size and location, removing it with surgery was out of the question. The first doctor he consulted said his only real hope was a liver transplant. Otherwise, he would be dead within two months.
“I panicked,” Mr. Stroud says. “I have two grandchildren I wanted to do things with. I would have done anything to change that prognosis.”
Mr. Stroud, 67, sought a second opinion from radiation oncologist Marsha Reyngold at MSK Commack. She explained that a powerful radiation approach offered at Memorial Sloan Kettering might be able to destroy the tumor.
“She gave me a ray of hope that this treatment could work and may save my life,” he says.
The technique involves using higher-dose radiation to deliver treatments to inoperable tumors of the liver and pancreas that have not spread to other parts of the body. Pioneered by MSK radiation oncologist Christopher Crane, the approach is giving people with large tumors of the liver and pancreas hope for a cure or longer-term survival. At the very least, Dr. Crane says, it can buy them time until a clinical trial might be available.
Aggressive Approach to Treatment
Tumors in the liver and pancreas often cannot be removed through surgery because they are too close to major blood vessels. Conventional radiation doses and techniques are not able to control these tumors, but higher “ablative” doses are able to successfully control 90 percent of tumors, Dr. Crane explains. Delivering these higher doses to larger tumors is particularly challenging because it is more difficult to protect the liver, stomach, and intestine, which are nearby.
Most radiation oncologists instead choose palliative treatment and deliver only about half the cumulative radiation dose needed to kill every cancer cell and control the tumor.
“Patients who have no surgical option have historically been undertreated instead of receiving potentially curative doses of radiation,” Dr. Crane says. “Our extensive experience delivering ablative doses in the upper abdomen enables us to have the courage and confidence to give treatments that effectively control the tumor.”
One key to giving larger doses safely is spreading them over a greater number of treatment sessions. Radiation dosage is measured in units called grays (Gy). A standard treatment for a liver or pancreas tumor would typically be 25 to 33 Gy given in five sessions. At MSK, patients might receive 67.5 Gy in 15 sessions or 75 Gy in 25 sessions. Although each individual dose may be slightly smaller, the cumulative biological dose is high enough to control the tumor while sparing nearby normal structures.
Such large overall doses could carry too much risk for toxicity or complications. But MSK’s radiation oncologists have the expertise to deliver the treatment without harming normal tissue. In fact, the treatment rarely causes anything other than mild fatigue.
Another critical feature of the approach is the ability to control and account for the movement of nearby organs. The biggest challenge is addressing the movement of organs from one treatment to the next. For example, air in the bowel or stomach can affect the position of multiple organs. When doctors look at the CT scan, they must be able to recognize changes in the patterns and interpret what they mean. This enables them to tell the difference between random, temporary motion and a more consistent shifting in position that requires a change in the treatment plan.
“The expertise needed for making these judgments can be developed only by working with a large number of patients,” Dr. Crane says. He is training a growing number of MSK radiation oncologists in the technique, including at MSK’s regional outpatient locations.
Cancer Care Close to Home
Mr. Stroud had hepatocellular carcinoma, the most common type of primary liver cancer. For such a large tumor, Dr. Reyngold recommended a radiation dose of 75 Gy, to be given over 25 sessions. Mr. Stroud received his treatment Monday through Friday over four weeks in August 2017 at MSK Commack.
Radiation therapy does not kill cancer cells right away. It can take weeks or months to know if it has been effective. Because of this, doctors often give chemotherapy or targeted drugs after the radiation to fight tumor growth in case the radiation doesn’t work. Mr. Stroud received a targeted therapy called sorafenib. When the side effects proved too much, his medical oncologist, Jia Li, switched him to the immunotherapy drug nivolumab.
After a few months, the tumor shrank dramatically. The doctors think the large radiation doses he received were the main cause. When a small recurrence appeared in the spring of 2018, MSK doctors were again able to treat him — this time with a minimally invasive technique called interventional radiology, which appears to have stopped the tumor growth.
Despite all the twists and turns of his treatment journey, Mr. Stroud says he is grateful for the extra time he has gained after being on the brink of death last year. “MSK made what was a horrible experience into one where I have hope,” he says.Back to top