Bright Grey and Scottish Provident have sought to clarify breast cancer cover from critical illness (CI) providers following recent changes made to their definitions.
Scottish Provident also announced it has paid more than £1bn to claimants since 2003.
The providers added additional cover for low grade prostate cancer and an early form of breast cancer known as ductal carinoma in situ (DCIS), both of which will receive a payment of up to 20% of the sum assured.
The move sparked a debate in the industry about the covering of less severe conditions and the definitions surrounding them.
Roger Edwards, proposition director for Bright Grey and Scot Prov, explained the differences of cover available and changes made by the providers.
"One aspect highlighted by the initial feedback is that there is lack of clarity around the level of cover offered for the early forms of breast cancer by UK CI providers," he said.
"Some providers will pay out for full mastectomy only, whereas others will pay out for mastectomy as well as other remedial surgeries such as lumpectomy.
"Lumpectomy is a less invasive surgery, resulting in a shorter and easier recovery time than mastectomy and is therefore a preferred option of those that have a choice," he added.
According to Edwards, almost 18,000 mastectomies were carried out in England in 2009-10 with a further 39,000 other types of breast surgery such as lumpectomies.
Scot Prov's £1bn total includes payments for life and CI claimants over the last eight years through its Self Assurance menu scheme, which was launched in 1996.
Since then it has paid more than £540m in cancer claims alone with an average figure for all CI claims reaching £76,234.
In 2010 this figure was £84,873 with life claims averaging £77,712.
It has also paid over £9m in children's CI claims.
Jennifer Gilchrist, senior product development manager at Scottish Provident, added: "Breaking £1bn for our payouts for life cover and CI underlines our commitment to ensuring that consumers and their families are financially protected in the result of illness or death."