Fulop, who played for nine English clubs after moving from MTK Hungaria to Tottenham in 2004, had a tumour removed from his arm in June 2013.
"I am sure that after a few months I will be ready both physically and mentally to continue playing football," the then 30-year-old said, but he did not return to action.
In February 2014 he was given a ticket to the League Cup final between Sunderland and Manchester City and again spoke of his hope that he could resume his career.
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On Thursday, after a prolonged illness, the keeper, who won 24 international caps, passed away.
A statement on MTK's official website read: "We are deeply sorrowful and grieved to announce that after a long illness, Marton Fulop has died."
Marton Fulop, West Bromwich Albion goalkeeper
Image credit: PA Photos
Fulop joined Tottenham as a Hungary Under-21 international and was sent out on loan to Chesterfield, Coventry City and Sunderland, whom he joined in a permanent deal for £500,000 in January 2007 without playing a game for Spurs.
He made 50 appearances in total for Sunderland before going on loan to Leicester City and then, famously, to Manchester City in an emergency loan deal for the final three games of the 2009-10 season.
Fulop joined Ipswich Town and also spent a season with West Brom before his career ended at Greek side Asteras.
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