NHS England predicts London cancer patients 'will double by 2030'
NHS England said cancer diagnoses need to be made in earlier stages of the disease
The number of people with cancer in London is expected to double by 2030, according to NHS England.
The organisation predicted 400,000 Londoners will be living with cancer by that point, which it said presented a "huge challenge".
A cancer strategy for London, aimed at increasing early diagnosis and reducing waiting times, has been released.
NHS England's Dr Anne Rainsberry said the capital's cancer services needed to "become better".
The Cancer Commissioning Strategy for London states that since NHS England last released a strategy for London in 2010, the cost of cancer care had escalated, budgets had become tighter and patient experience had remained poor.
A survey by MacMillan Cancer Support in 2013 showed of the 10 English NHS trusts receiving the worst feedback from cancer patients, nine were in London.
NHS England said patient experience should be made a higher priority by hospitals and other service providers.
A spokesman said the organisation aims to ensure all hospitals take action to reduce waiting times, improve access to specialist cancer nurses and make travel and parking easier.
The updated strategy also aims to increase the number of diagnoses of cancers in their early stages.
Dr Rainsberry, the Regional Director for NHS England (London), said that "more than a quarter of cancers are diagnosed in A&E or as an emergency referral".
"We need to change services so that London's health services become better at preventing cancer and detecting it earlier."