Platinum keyword in a somewhat secondary TLD. I'm not sure about how content would place in the SERPs - will it rank high for people searching for mesothel information in North America or would it be mainly coming up in meso searches associated with Singapore?
If it's the latter, then you would lose out on organic placement for the biggest market for Mesothelioma issues (the USA). On the other hand, if you develop it with enough pertinent content, it could score high nonetheless even on non geo-specific searches.
I'd say $xxx undevelopped, and .... at least $xxxx developped (maybe much more if you do some creative and serious SEO.)
Good luck!
Rob