I read the latest on HRT fairly carefully because I used the combined pill for 5 years and everytime there is a scare I have a bit of a panic. From reading several recent sources I think its correct that the study looked at a large number of ladies aged between 50 and 70. It was a solid bit of science where the groups studied were matched for lifestyle, weight, diet etc. For those who never used HRT 6.3% got breast cancer, for those who used HRT it was 8.3%. In other words there is a 2% increased risk and the risk seems to last for about 10 years after HRT is stopped.
As Esspee rightly points out, however, there are other risk factors for breast cancer relating to family history, life style, diet, smoking and alcohol. Some of these are under our control. The link between alcohol use and breast cancer risk, for example, is at least as strong as that of HRT, yet this fact has received little publicity. Obesity is another large risk factor and again the role of diet and weight have not been greatly highlighted. (For info on alcohol the Journal of Clinical Medical Research has a good publication: www.ncbi.nlm.nih.gov/pmc/articles/PMC3318874/).