Nine of London's NHS trusts are at the bottom of a league table measuring cancer patient experience across England, according to Macmillan data.
The cancer charity has published a league table which reveals poorest and best performing organisations.
Performance is determined on factors such as; whether diagnosis and treatment options were explained clearly; whether patients felt supported in their care; and whether they felt they were treated with respect.
Ciarán Devane, chief executive of Macmillan Cancer Support, said: "Though many hospitals have made an improvement, far too many cancer patients are being let down by hospitals failing to provide an adequate level of care. Patient experience and non-clinical needs must be given as much priority as medical activities.
"Patient experience is one of the government's five key measures for success in the NHS, so trusts need to take heed and work with Macmillan and others to urgently improve the care they offer cancer patients. I am encouraged many trusts are taking this seriously."
"Imperial, while still at the bottom of the table, is committed to addressing the problem and working well with Macmillan and cancer patients. But these things take time, and won't happen if they do not have sustained, top-level commitment."
Professor Jane Maher, chief medical officer of Macmillan Cancer Support and clinical oncologist, said hospital target hitting with cleanliness and safety was being prioritised over care.
She added it was "absolutely vital" patient experience was prioritised as it made a real difference to patients recovery after gruelling cancer treatment.
Imperial College Healthcare NHS Trust scored particularly badly while Harrogate and District NHS Foundation Trust scored highly on communication. The most improved is Portsmouth Hospitals NHS Trust.
Diana, a 32-year-old cancer patient with recurrent Hodgkin's Lymphoma, developed complications during stem cell transplant.
She said of treatment at a London Hospital Trust: "From the first day they promised to get a specialist to see me. Three weeks later my symptoms were worse and no doctor had come to see me. I wasn't listened to, the doctors and nurses left me in such pain that I couldn't even walk."
An urgent specialist referral was promised when she was discharged but the letter was never sent.
"I wrote and called the cancer team daily, crying over the phone begging them to get me an appointment with the specialist - it took three months to get a referral and by that time it was so bad I had to have an operation," she said.
"If they'd treated me earlier I would have only needed creams."
Overall the survey showed good improvement across trusts in providing information about patients' care; but many NHS trusts have seen no improvement in any of the areas measured.
The research also revealed that breast cancer patients in England had the best patient experience, while sarcoma patients continue to have the poorest.
Other areas for concern in the survey were whether patients were given enough support from health and social services when they left hospital.
It also highlighted whether adequate emotional support and financial information was being provided.
Macmillan has produced a Top Tips Guide for Patient Experience to help trusts improve.
