Tito Vilanova will step down as Barcelona manager after suffering a relapse following the removal of a cancerous tumour last year.
Barcelona have confirmed that Vilanova is undergoing emergency surgery in a hospital in Barcelona on Thursday to attend to problems with his parotid gland, and a press conference will be staged later on Wednesday.
A short-term replacement for Vilanova is expected to be confirmed, although Barcelona are hopeful his treatment 'will be compatible with his work life'.
The 44-year-old will be hospitalised for three or four days and will then undergo chemotherapy and radiation treatment, lasting about six weeks. Barcelona have requuested that his privacy be respected in this time.
Vilanova was promoted to Barcelona manager following the departure of Pep Guardiola in the end of last season, and has overseen the best start to a campaign by any team in the history of La Liga.
Barcelona have won 15 and drawn one of their opening 16 fixtures, and are currently 13 points ahead of last season's champions Real Madrid.