The recently published DEBATES IN MEDICINE (230:95-109, 1974) point out some of the crucial problems that persist in the evaluation of the proper treatment of breast cancer. Attempts to define treatment on the basis of differences in survival rates of 5% to 10% in uncontrolled retrospective studies make no sense in terms of what we know about the disease. Furthermore, even the prospective randomized studies do not clearly define the elements necessary for proper evaluation of treatment.
Not all cancers of the breast behave in the same manner. It is fundamental in understanding breast cancer treatment to define what (little) we know about its natural history. In terms of the average doubling time (30 days), a 2-cm lesion has been present for approximately eight years prior to diagnosis. If the volume of a spherical cancer is given by the formula, 1/6πd3 (or 4.189×r3), then an increase in size from
Gardner B. Breast Cancer Revisited. JAMA. 1975;232(7):742–743. doi:10.1001/jama.1975.03250070038022