Updated

A terminally-ill teenager, whose cancer charity appeal has won worldwide support and admiration, has revealed his condition "dramatically improved" after he "coughed up a tumor."

Stephen Sutton disclosed details of what he described as "the most bizarre but fortunate twist in the tale yet" on his Facebook page, on which he has published a bucket list of things he wants to do before he dies.

From around mid-afternoon on Sunday he developed a slight cough and later wrote: "After lying there for a bit longer the coughing increased and then suddenly the shortness of breath became incredibly severe.

"Amongst frantic hand pointing and panicking I felt like I was like suffocating. Then I forced out an oval red stained solid object through my mouth."

Immediately afterward, Sutton said his breathing and airway felt much clearer.  He said he then spent the next hour violently coughing and choking, before his breathing finally stabilized.

"The doctors have discussed what's happened, and the only plausible conclusion is that I've literally coughed up a tumor," he wrote.

The 19-year-old has now raised more than $5 million for the Teenage Cancer Trust, with more than 122,000 people - including celebrities Stephen Fry and Russell Brand - pledging their support.

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