On Wednesday, Nascimento had posted a video of the former Number 10 singing the anthem of Santos, his former club.
The three-time World Cup winner had undergone surgery for a suspected colon tumor, detected during a routine checkup, on September 4, and left intensive care last week.
The results of the biopsy have not been made public.
Considered by many to be the greatest footballer of all time, Pele has been in poor health in recent years, and has had various stints in hospital.