“It's kind of mind-boggling,” Trebek told people People magazine in a new interview. “The doctors said they hadn't seen this kind of positive result in their memory…some of the tumors have already shrunk by more than 50 percent.”

That an extremely positive results considering Trebek’s grim diagnosis of Stage 4 pancreatic cancer. This is especially true since the greatest difficulty with pancreatic cancer is the solid tumors. "It is the solid tumor [pancreatic] cancer that has the worst prognosis. It is right now the third leading cause of cancer death, soon to be the second leading cause of cancer death in the United States," Dr.  Allyson Ocean, Medical Oncologist at Weill Cornell Medical Center, told SurvivorNet in an interview prior to the first announcement of Trebek’s diagnosis. "Mortality is rising because it is caught so late and we don't have enough effective medications against the cancer."

And what’s called a “stroma” makes it difficult for doctors to get at the tumor itself.  "The cancer cells are surrounded by what is called a stroma, and the stroma serves as a barrier for medications to get in to the cancer to kill it," says Dr. Ocean. Stroma is tissue that surrounds the cancer tumor.

And that usually includes chemotherapy. "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."

In his always grateful and positive way, Trebek also took the time to note to People the help of fans and friends who have supported him throughout the entire process. “I've got a couple million people out there who have expressed their good thoughts, their positive energy directed towards me and their prayers,” he says. “I told the doctors, this has to be more than just the chemo, and they agreed it could very well be an important part of this.”

“I've got a lot of love out there headed in my direction and a lot of prayer, and I will never ever minimize the value of that” he says.

The American Cancer Society estimates that about 56,770 people in the United States will be diagnosed with pancreatic cancer this year alone, and that 45,750 people will die of the disease. The 5-year survival rate for people with pancreatic cancer is 9%.

Trebek also recently  said that if chemotherapy goes well, there may be an opportunity for his to use immunotherapy, or drugs which use the patient’s own immune system to attack cancer cells. "If we've managed to get rid of some of the tumors, then it'll be great, and then I can go to immunotherapy, because they've discovered that my cancer is a specific mutation that responds well to certain kinds of immunotherapy," said Trebek in an interview with Canadian news outlet The National.

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