Some years ago we were able to confirm reports on the prognostic meaning of mitotic figure counting in breast cancer on a retrospective series of 104 breast cancer cases (Hum Pathol 26: 47-52, 1995). An independent influence of mitotic figure counting on prognosis could be proven in stage I and stage II tumors. Using the same methodological approach, the investigation has been repeated recently on a prospectively collected series of breast cancer patients (n = 108). A strong benefit for the patients' outcome was found for patients with stage II tumors (p = 0.0093), but not for patients with stage I tumors (p > 0.05). Regarding the differences between the two studies, most probably the effects of therapeutic changes between the late 1970s and the late 1980s and aspects of the patients' selection may be responsible.