Local therapy, systemic benefit: challenging the paradigm of biological predeterminism

This paper briefly reviews the historical evolution of paradigms that have been purported to characterise the clinical behaviour of breast cancer, with the intention of guiding treatment approaches. Results from randomised clinical trials and the explosion of knowledge in the area of cancer biology have discredited the monolithic paradigms that had dominated thinking about breast cancer in the past. Contemporary notions of breast cancer biology recognise that, although some cancers disseminate well before becoming clinically detectable, acquisition of a metastatic phenotype can occur at any point (or not at all) in the local evolution of the tumour. As a consequence, both systemic and timely local--regional therapies can be expected to influence disease dissemination and patient survival. This is consistent with results observed in clinical trials, overviews of which indicate that prevention of four local recurrences will, on the average, prevent one death from breast cancer. Optimisation of local-regional treatment is an important goal in breast cancer management.