The Dirty Dancing star is believed to have been told the news last month.
Several US publications are claiming that 55-year-old Patrick has 'only 5 weeks to live'.
But his doctor has rubbished the rumours.
'Patrick has a very limited amount of disease and he appears to be responding well to treatment so far,' states personal physician Dr George Fisher.
'All of the reports stating the timeframe of his prognosis and his physical side effects are absolutely untrue.'
The actor's rep tells E! Online that the actor isn't letting the diagnosis get to him: 'Patrick is continuing his normal schedule during this time, which includes working on upcoming projects.'
Find out more about the diagnosis and details on pancreatic cancer
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