Prognostic factors in NSABP studies of women with node-negative breast cancer. National Surgical Adjuvant Breast and Bowel Project.

Twenty-two pathologic (including estrogen and progesterone receptor status) and four clinical features of 950 node-negative stage I invasive breast cancers from 950 women enrolled in the National Surgical Adjuvant Breast and Bowel Project protocol B-06 were analyzed for their possible prognostic significance. Univariate analyses revealed 10 characteristics that were significant at the 1% level. Only three of these--notably nuclear grade, histologic tumor type, and race--were found to be significant when entered into a Cox regression model. Patients whose tumors exhibited a good nuclear grade fared significantly better than those whose tumors were scored as poor. Similarly, a significantly better prognosis was noted when the histologic type of cancer was found to be "favorable" (mucinous, tubular, or papillary) than when it was "intermediate" (NOS, "Not Otherwise Specified," combination; typical medullary; and lobular invasive) or "unfavorable" (NOS pure and atypical medullary). Blacks exhibited a worse prognosis than whites. Survival was 94% at 8 years when the nuclear grade was good and the tumor type favorable, but only 54% when the nuclear grade was poor and tumor type unfavorable. Patients with one favorable and one unfavorable feature exhibited an intermediate survival. A brief overview as well as our own preliminary experience indicates that the combined use of these two prognostic pathologic parameters may be as good as and in some instances a better predictor of survival in node-negative patients than information derived from more "objective" methodologies such as flow cytometry, receptor analyses and tumor labeling indices or the demonstration of oncogene overexpression. Assessment of the pathologic parameters is simple, universally available, and quick and requires only modest training to be reproducible.