North will be expected to drive awareness of the charity's counselling services and advice helplines, as well as its work on the financial implications of cancer.
The charity is seeking to emphasise its role as a provider of care and support for cancer sufferers and to position itself as the cancer charity that helps survivors.
The move is part of an attempt to ensure potential donors do not confuse the organisation with terminal cancer or treatment research charities.
'As soon as anyone thinks of cancer, we want them to think of Macmillan Cancer Relief,' said Macmillan PR manager Peta Delahunty, who will report to North.
North will lead a team of ten, comprising three media and PR functions: fundraising, celebrity liaison and campaigns and services.
A major element of her remit will be to raise the profile of the charity's work with a range of different types of carers for cancer sufferers.
'People know there are Macmillan nurses, but we also have doctors, radio-graphers, physiotherapists, palliative carers, and counsellors,' said Delahunty.
North reports to Lynda Thomas and Hilary Cross, who job-shared the head of media position until they were promoted last year. Thomas and Cross now job-share a newly-created role of Macmillan assistant director of communications.