The Blaugrana chief has stressed that the 44-year-old's health is all that matters, and is confident that he will make a full recovery from his illness
The 44-year-old will be taking a hiatus from the game while he undergoes chemotherapy and radiation treatment that is scheduled to last around six weeks.
"Tito is strong, very strong. He’s shown that he’s strong and we’re convinced that he’ll be back with us soon," Rosell said at a press conference.
"The most important thing is that he recovers and that he has the necessary tranquility to undergo this [healing] process.
"I liked seeing his face. He looked strong. He has extraordinary mental strength, he only looked worried for his wife, children and parents.
"We are a strong and unified club, we can overcome any adversity."
Vilanova will be replaced by assistant Jordi Roura during his absence.