Mr Justice Bodey ruled today that Neon Roberts can undergo surgery on a "residual tumour" but it is not yet clear whether he can receive radiotherapy.
The ruling in the Family Division of the High Court was due to decide whether Neon should undergo radiotherapy treatment following surgery, against the wishes of his mother.
That issue was put to one side to deal with the more pressing decision regarding his operation.
A High Court judge has ordered that a 7-year-old boy from Devon must have surgery tomorrow - going against the wishes of the boy's mother.
Sally Roberts, who earlier this month ran away with her son Neon, has gone to court because she doesn't want him to have radiotherapy treatment for cancer.
A High Court judge was asked to decide whether Neon Roberts, the seven-year-old boy at the centre of a legal dispute over cancer treatment, can undergo more surgery. Neon, originally from Devon, has already had surgery on a brain tumour.
Doctors say he needs another operation. But his mother, Sally Roberts, will not consent. The judge said he aimed to make a decision later today.
A High Court judge is expected to receive updates about the condition of Neon Roberts, formerly from Tiverton in Devon. The seven year old is at the centre of a legal dispute over cancer treatment.
His mother was against his undergoing radiotherapy following treatment for a brain tumour, fearing it would cause her son long-term harm. But his father, Ben, who is separated from Neon's mother had agreed to the radiotherapy. Doctors had said he might die within months without it.
A mother who disappeared with her young son to stop him being treated for cancer says she had no choice.
37-year-old Sally Roberts disappeared from her home in Tiverton with seven year old Neon because she was worried that radiotherapy would be damaging.
She says she needs more evidence that treatment is necessary and other options need to be explored. The case was heard at the High Court and a judge will make a decision next week. Sally spoke exclusively to Daybreak this morning. This is the full interview.
A woman who ran away with her seven-year-old son to stop him having cancer treatment said she will agree to radiotherapy if doctors find his brain tumour has returned.
Sally Roberts from Devon disappeared with Neon after a dispute with her estranged husband Ben over the boy's condition and treatment.
But doctors said Neon could die within months without radiotherapy and Ms Roberts has now backed down, saying her son will have to have the treatment if irregularities on a recent scan prove to be sinister. A further court hearing is scheduled for December 18.
A judge has postponed a ruling over whether a mother who was living in Devon should prevent her seven year old son from receiving radio therapy for brain cancer.
His grandparents, who live in North Tawton, say they're relieved after what has been a traumatising week for their daughter after a nationwide search was launched for her.
Richard Lawrence reports: