The Brazilian-born striker was named in Germany coach Joachim Low's initial squad for Euro 2012, despite only fleeting appearances for his club last season.
Cacau was one of three players left behind by Low and the 31-year-old believes his lack of opportunities in the Bundesliga was to blame.
"Not playing so often for Stuttgart cost me my place at the Euros," he told Bild. "I have been thinking a lot about what has not been working over past 18 months and the main reason is that I have not been allowed to play in my favourite position.
"I cannot show my full strength as the lone striker. If I do continue playing here, then I must play in my position.
"The coach explained that Tamas (Hajnal) is ahead of me and he cannot promise to me at the moment that I will have a regular place.
"But if I carry on getting so few appearances, then I can forget about my dream of playing at the World Cup in Brazil.
"I will listen to offers and if everything is right, then I can imagine leaving - I want to play."