Irrationality in the management of breast cancer. I. The staging system.

The historic development of breast cancer staging began early in the 20th century with the simple concept of early localized disease, spread to regional nodes, and the presence of distant metastases. This last group often was divided into patients with advanced but perhaps still curable locoregional disease and incurable patients with distant metastases. As increasing numbers of prognostic factors were recognized, efforts were made to incorporate them into the staging systems to combine patients with similar prognosis into the same stages. These attempts resulted in the development of four classifications, namely, the Columbia, Manchester, International, and American tumor-node-metastasis (TNM) staging systems. Although many benefits of staging were reported, the most important was that of permitting valid comparisons between different treatments and different institutions. Many success-limiting factors were noticed during the developmental years, and even though the TNM system has been accepted, numerous speakers and authors present their staged data in a confusing and ambiguous manner. Recommendations are made that would permit clarification of presentations to general medical audiences along with recognizable statistical validity.