Less than a month after announcing that he has completed his chemotherapy, the TV game show host reveals to 'Good Morning America' that his pancreatic cancer battle has taken a turn for the worse.

• Sep 18, 2019

AceShowbiz - "Jeopardy!" host Alex Trebek is to undergo another round of chemotherapy as his pancreatic cancer battle has taken a turn for the worse.

The 79-year-old, who returned as the host the U.S. TV game show just last week (September 9) after an earlier round of treatment, has now revealed he needs to undergo chemotherapy again.

"I was doing so well," he said during an interview on U.S. TV show "Good Morning America" on Tuesday, September 17. "And my numbers went down to the equivalent of a normal human being who does not have pancreatic cancer. So we were all very optimistic. And they said, 'Good, we're gonna stop chemo, we'll start you on immunotherapy'."

However, he said that recently he had felt ill and doctors told him he needs more chemotherapy to fight the disease.

"I lost about 12 pounds in a week. And my numbers went sky high, much higher than they were when I was first diagnosed. So, the doctors have decided that I have to undergo chemo again and that's what I'm doing," the Canadian compere added.

He also said that his cancer had caused him "excruciating pain" and "fatigue."

Alex announced he had stage four pancreatic cancer in March, but last month delighted fans by announcing he had finished his chemotherapy and would be returning to work on "Jeopardy!".

He had already filmed the current 35th season of the quiz show before returning to treatment.