"Unfortunately, it's true," the 52-year-old said on the brink of tears. "Last week, I had a medical examination in Sofia and then I went to Austria and they confirmed the diagnosis."
Dimitrov, who was Bulgaria coach in the late 1990s, is considered one of the most successful managers in Bulgaria.
He led Litex Lovech to the league title and has also coached Levski Sofia, Lokomotiv Plovdiv, Russian club Amkar Perm and Saudi Arabia's Al-Nassr and Al-Qadisiya.
"You know my character," Dimitrov, known for his fiery temper, added before Sunday's league match against his old club Levski. "We have a game against Levski and I returned [to Bulgaria] because we must win it. We owe this to our fans."
Chernomorets are third with 18 points from eight games ahead of Levski on goal difference. CSKA Sofia are top with 24 points.
"It's clear I now have a fight ahead of me and I'll fight to win," said Dimitrov who will travel back to Austria for chemotherapy treatment after Sunday's game.
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