karenann,
The article RobinP posted about is from the results of the 2005 Early Breast Cancer Trialists Collaborative Group. Here is a link to the page on their website where you can access the full report:
http://www.ctsu.ox.ac.uk/~ebctcg/. You want to go under "Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the randomised trials" and click on the link for the pdf file "final typescript of the paper with tables and figures."
The information about "untreated patients" means patients who had surgery with or without radiation but neither tamoxifen nor chemotherapy. (The studies do not include any patients treated with herceptin, taxanes or aromatase inhibitors - they were begun so long ago the modern drugs were not in use.) The studies were begun in the early 1980's (I can't imagine a study today where there would be no adjuvant treatment) and the populations have had a chance to mature for 20 years, giving probably the best picture we have now for the natural history of early stage bc. The information shows that hormone negative patients recur largely in the first five years, then their risk begins tapering off. Hormone positive patients have fewer recurrences in the first five years, but the chances of recurrence continues at a steady level out to 10 years and beyond. At the ten year mark and beyond, the risk of recurrence for hormone negative patients is actually less than that for hormone positive patients
in an untreated population.
Hopeful