The natural history of breast cancer

The natural history of breast cancer is a contentious issue. Some authors a rgue that it is a systemic disease and that local therapy does not affect m ortality. Others maintain that it is a local disease at inception and that locoregional therapy does reduce mortality. There are, of course, no random ized, prospective trials comparing local therapy to no treatment. Thus, the true effect of local therapy on breast cancer mortality remains open to sp eculation. Nonetheless, there are trials that have examined the effect of s creening or permutations in local therapy on mortality. This article discus ses some of these trials and their relevance to the natural history of brea st cancer.