Natural history of breast cancer.

Retrospective analysis was made of 3,918 cases of breast cancer seen during 1954-1964. Median survival was 4.5 years and 30% of patients survived through a 10-year period. For stages I, II, and III patients, the mortality increased during 1-4 years after diagnosis and then slowly declined. Beyond 15 years, stage III patients assumed the same mortality (5%) as those with lesser disease; 58% excess of deaths from all causes after 15-20 years showed that breast cancer was not curable within 20 years but ultimately, taking account of clinical status, 51% of 5-year survivors with stages I-III disease are cured.