Breast cancer--a challenge to the contemporary paradigm.

There is much triumphalism about the apparent progress in the diagnosis and management of breast cancer and yet the impact on mortality from this disease in both the United States of America and Europe has been quite trivial. The early results of adjuvant systemic therapy have been sustained out of 15 to 20 years, which presumably accounts for the majority of the mortality reductions we are seeing, yet it is my impression that progress has slowed down, if not plateaued. For that reason it is time to reconsider our prejudices and recognize that we will need another conceptual revolution before there is the next important incremental step forward. It is here proposed that the current concepts on the initiation and progress of micrometastases are wrong and that we need to develop a new paradigm based on our current knowledge of cell and molecular biology which recognizes that occult metastases that ultimately are the cause of breast cancer mortality are complex organisms, maintained in the state of dynamic equilibrium. This equilibrium can be perturbed by 'premature' surgery, so that the whole concept of 'early diagnosis' and prompt treatment might be fundamentally flawed. Therapeutic interventions that may control rather than 'cure' breast cancer using biological specific modalities rather than non-specific cytotoxic drugs could provide some of the answers. An even more radical challenge to the contemporary paradigm is suggested. Perhaps not all metastases are cellular phenomena, maybe in vivo transfection by endogenous retroviral-like particles allows breast cancer to escape destruction by chemotherapy?