Is the sentence correct?

[Tan Elaine]

Getting back to Jason, he seemed to be cured of his cancer. However, seven months later, he suddenly died of the disease.

1. Is "Getting back" correct in the sense of talking about Jason when he was mentioned earlier in the story. If not, how should I phrase it?
2. Is "his" needed?
3. Are there any other errors in the sentence?

Thanks in advance.

 

[corum]

How about this:

Returning to the issue concerning Jason, he seemed to have eradicated all symptoms of cancer. However, X months later, he died out of the blue.

Your sentence is a tad awkward stylistically, in my opinion.

 

[Raymott]

Getting back to Jason, he seemed to be cured of his cancer. However, seven months later, he suddenly died of the disease.

1. Is "Getting back" correct in the sense of talking about Jason when he was mentioned earlier in the story. If not, how should I phrase it?
"Getting back to Jason, he seemed ..." is ambiguous. In structures like this, "he" would normally refer to the person who is getting back to Jason, not to Jason himself. corum has given you an alternative, but it has the same problem.
Perhaps these are better:
"Getting back to Jason: he seemed ..."
"Getting back to Jason - he seemed ..."

2. Is "his" needed? No, but you can use it.
3. Are there any other errors in the sentence? Not that I can find.

Thanks in advance.

R