Medical insurance question

[ubersonic]

Hey all, I don't think asking a question about medical insurance triggers the no medical advice request rule but if so please delete.

Anyway just wondering if anyone knows how the laws works around medical insurance (or insurance in general) work with regard to this scenario as it came up in conversation today and Google is no help:

1. Person pays insurance policy for years.
2. Person gets brain cancer.
3. Person lets insurance payments lapse due to brain cancer.
4. Person is diagnosed with brain cancer.

Do they have any right to claim as they had an active policy at the time they contracted the illness? Or are they screwed because they don't have the policy anymore.