Travel insurance which accepts recent investigations

[skylark15]

My 18 year old grandson has recently had a colonoscopy (for loss of dark blood P/R) and a polyp was found, removed and the report says: "No malignancy".

He's already booked a flight to SE Asia, leaving on 10th February and needs reasonably priced backpackers' travel insurance. He understands he must declare this investigation and its result. Can anyone recommend a company that would accept him in these circumstances? Thank you.