United Kingdom, April 28 -- Sir Sam Neill is cancer-free.

The 78-year-old actor - who is perhaps best known for playing Dr. Alan Grant in Jurassic Park - was diagnosed with stage 3 blood cancer four years ago, but Sam is now cancer-free thanks to an innovative form of treatment.

Sam told 7News Australia: "I've been living with a particular type of lymphoma. I was on chemotherapy and the pretty miserable business but it was keeping me alive.

"Then the chemo stopped working. I was at a loss and it looked like I was on the way out, which wasn't ideal, obviously."

Sam ultimately underwent CAR T-cell therapy to train his immune cells to recognise and destroy cancer, and the results have been remarkable.

The actor - whose film credits also...