Acute leukemia with t(4;11) following treatment for breast cancer

We report the case of a 51-year-old woman presenting t(4;11) acute undifferentiated leukemia 19 months after initiation of adjuvant radio-chemotherapy for a breast cancer. Morphology of the blasts was FAB L2 and cytochemical and immunological studies were in favor of an undifferentiated leukemia. A possible relationship between t(4;11) leukemia and exposure to carcinogens is discussed.