The 86-year-old judge “tolerated treatment well” and the tumour has been “treated definitively”, the court said in a statement.

Ms Ginsburg has been diagnosed with cancer before and has suffered fractured ribs from falls.

Justices of the court serve for life or until they choose to retire. As the senior liberal justice on the court, Ms Ginsburg’s health is watched closely. In the event anything happens to her, her supporters worry that her place on the court will be taken by a conservative justice.

The court currently has a 5-4 conservative majority.

The statement said: “The abnormality was first detected after a routine blood test in early July, and a biopsy performed… she cancelled her annual summer visit to Santa Fe, but has otherwise maintained an active schedule.”

It added: “The tumour was treated definitively and there is no evidence of disease elsewhere in the body… no further treatment is needed at this time.”