Mark Hoppus received encouraging news from his doctors as he battles diffuse large B-cell lymphoma (DLBCL): chemotherapy is working. The Blink-182 singer shared a health update with fans on Monday, nearly a week after going in for a PET scan.

Mark Hoppus says chemotherapy is working amid his cancer battle. (Photo: WireImage)

"I still have months of treatment ahead, but it’s the best possible news," the 49-year-old wrote. "I’m so grateful and confused and also sick from last week’s chemo. But the poison the doctors pump into me and the kind thoughts and wishes of people around me are destroying this cancer. Just gonna keep fighting…"

Hoppus opened up more about his cancer diagnosis last week, revealing he’s fighting DLBCL, an aggressive type of non-Hodgkin’s lymphoma.

"My cancer’s not bone-related, it’s blood-related. My blood’s trying to kill me," he exclaimed. It’s the same type of cancer his mother had — and beat.

"My classification is diffuse large B-cell lymphoma stage IV-A, which means, as I understand it, it’s entered four parts of my body," Hoppus added. "I don’t know how exactly they determine the four-part of it, but it’s entered enough parts of my body that I’m stage IV, which I think is the highest that it goes. So, I’m stage IV-A."

Hoppus said he has "chemo brain," a side effect from the multiple rounds he’s done.

"I forget things I should have just on call, like people’s names, song titles, like anything. I just forget stuff," he revealed, adding it "really sucks."

Fans around the world have rallied around the musician since he publicly shared his cancer diagnosis last month and are happy to hear the latest update.

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