Many long-term survivors of cancer are not getting the help they need to cope with the after-effects of the disease, experts warn.
More than 60% of adults with cancer can expect to live five years or more, according to an article in the European Journal of Cancer.
Yet they are left "in limbo" to deal with ongoing symptoms from their disease or harsh cancer treatments.
The government said it was working to improve services for cancer survivors.
Professor Marie Fallon, an expert in palliative medicine at the University of Edinburgh, said the number of people living with the effects of cancer was rising as more and more people were surviving the condition.
There is an enormous population of long-term survivors of cancer, many of whom are living with a range of symptoms
Professor Marie Fallon
She added that cancer survivors would suffer ongoing symptoms but often be confused about whether they were treatment-related or whether they were a sign the cancer had come back.
"Traditionally, palliative care has been aimed at one end of the spectrum where it is used to help patients near the end of their lives," she said.
"However, there is an enormous population of long-term survivors of cancer, many of whom are living with a range of symptoms."
"These patients exist in a limbo.
"They fall between two stools - they have finished being treated by oncologists, but are not receiving the care and support from palliative care teams that patients at the end of life receive."
She added the ongoing problems, which included pain, swelling and depression could result in poor quality of life.
Better integration was needed between oncology services and palliative care to prevent people falling through the gap, she said.
And there needs to be a clear agreement of where patients can access help and who should be responsible, she added.
Professor Alexander Eggermont, president of the European Cancer Organisation, said: "To be cured from cancer, but living with symptoms that are related to often complex multi-disciplinary treatments involving surgery, radiation therapy and chemotherapy is already difficult enough.
"To reintegrate into society, resuming work full or part-time adds to the complexities and socio-psychological pressure that an ever-increasing number of former-patients have to deal with.
"We better start tackling these issues now as they will only increase in number and magnitude."
A Department of Health spokesperson said deaths from cancer in people under 75 fell by 17% between 1995 and 2006.
"The Cancer Reform Strategy published in December 2007, recognised that the services and support available to those living with and beyond cancer needs to be improved and announced the establishment of a new National Cancer Survivorship Initiative to deliver this."