The 44-year-old, who had surgery to remove a tumour on the same gland last November, is due to remain in hospital for “three to four days” after the operation.
A statement from Barcelona’s medical services revealed despite the news, Vilanova could remain in charge of the first-team squad while undergoing his treatment.
“In monitoring the process of his parotid gland, an extension of the pathology was detected, requiring surgical treatment on Thursday,” the statement on fcbarcelona.es read.
“An extension of the pathology has been detected in (Vilanova’s) parotid gland. The manager requires surgery which he will undergo this Thursday. He is expected to remain in hospital for three to four days.
“After the surgery, Francesc ‘Tito’ Vilanova will undergo chemotherapy and radiation treatment for approximately six weeks. During this time, and depending on how well he recovers, Vilanova’s treatment may be compatible with his work life.
“Keeping in line with the patient’s wishes, we urge respect and privacy during this process.”
The statement confirmed a press conference with president Sandro Rosell and director of football Andoni Zubizarreta will take place at 6.45pm (BST) tonight.