[Breast cancer 1983. Facts and questions].

Several longterm follow-up studies in operable breast cancer have revealed the heterogeneity of the disease, with a high or low annual mortality rate due to systemic disease and with a cured group. These various biologic patterns cannot at present be defined on the basis of the available prognostic variables, possibly because accurate recognition of single and multiple tumors is lacking. Modern locoregional treatment is often based on the assumption that systemic disease occurs regularly and as a result of very early biologic predeterminism, and that, therefore, locoregional residual disease is of minor importance. This hypothesis must be questioned in the light of recent literature: no controlled trials are available which demonstrate that locoregional residual disease is harmless as far as systemic dissemination is concerned. Screening data and treatment results in minimal and subclinical cancer suggest that in most cases the systemic disease originates as a result of local and locoregional growth progression. In consequence, the possible existence of local or locoregional residual or multiple disease must be considered in planning treatment.