Macmillan Cancer Support has highlighted rising fuel poverty among cancer sufferers and called for Government support.
The charity said in 2011 the number of financial grants it gave to cancer patients to help with fuel bills rose by 172% over the last five years.
This equated to one-off payments totalling £2,548,563 to 12,669 cancer patients last year.
Nationally, a recent poll for price comparison website uSwitch.com found almost four million households - 14% of the total - are in debt to their energy supplier.
Although this is 5% down on last year down from 19% last year, for those still in debt the majority are worse off, with the average amount owed 4% higher than last year.
Mike Hobday, director of policy and research at Macmillan Cancer Support, said: "These new statistics show that the Government needs to act urgently upon the recommendations in the Hills Fuel Poverty Review and prioritise people with long-term illnesses, such as cancer, for support in paying their energy bills."
"Cancer patients often need to spend more time at home, leading to a rise in fuel bills at a time when, for almost four in ten, their household income on average halves.
"Many cancer patients find themselves in debt or are forced to cut down on other daily essentials, such as food, as they struggle to meet the rising cost of their energy bills."
