Former Dancing with the Stars contestant Tommy Chong has cancer again.

The Cheech & Chong star star, 77, revealed he's currently undergoing treatment for rectal cancer, Us Weekly reported.

"I've had some medical issues lately," Chong told Us on Tuesday. "I got diagnosed with rectal cancer."

Chong had reportedly battled through prostate cancer in 2012. Back then, Chong used marijuana for medicine and relief -- as he's an advocate for the decriminalization of marijuana -- and he's apparently using the herbal aid again.

"I'm using cannabis like crazy now, more so than ever before," the comic said. "I'm in treatment now... either I get healed or I don't. But either way, I'm going to make sure I get a little edge off or put up."

Chong also revealed he's doing some uplifting, inspirational reading to help him get through this tough time. The book is called Spiritual Power of Truth by Joel S. Goldsmith.

"It's what's kept my head up," Chong noted. "So that's my book."

Chong and his pro partner Peta Murgatroyd were the ninth couple eliminated from Dancing with the Stars' nineteenth season. Murgatroyd became increasingly more surprised every week to learn they had advanced to the next phase of the competition. She didn't expect they'd last nearly as long as they did.