Dog the Bounty Hunter's Wife Beth Chapman Started Chemo for Throat Cancer

Dog the Bounty Hunter's wife, Beth Chapman, has started treatment to help eradicate throat cancer recently rediscovered by doctors ... and so far, so good, TMZ has learned.

Sources close to Beth tell us she's going through chemotherapy, which we're told started a couple weeks ago. Our sources say she and Dog have been traveling to L.A. to receive the treatments, and that she's been spending the majority of her time at their family home in Colorado in the meantime.

We're told the level of cancer remains the same -- very serious. The good news ... our sources say while the chemo has been tough, Beth is responding well and is in good spirits.

TMZ broke the story ... doctors found Beth's cancer had returned during an emergency surgery two months ago to clear a blockage in her throat that made it difficult for her to breathe. She beat the same cancer in 2017, but sadly it's back.

We got Dog out in Los Angeles shortly after the emergency surgery who let everyone know just how serious Beth's condition was ... and he thanked fans for their support.

Her family had planned to stay in Colorado as they considered their next steps.