Overall survival of patients stratified by the hierarchic classification model proposed by our study. The survival curves show clear separation of patients into the good, intermediate, and poor prognosis category, a difference that was statistically significant. Groups were formed by the stratification according to the presence or absence of specific genetic abnormalities. The poor prognosis group includes patients with – 17p13.1, t(4;14)(p13;q32), and/or t(14;16)(q32;q23); the intermediate prognosis group includes those patients with Δ13 who did not have the aforementioned abnormalities; and the good prognosis group includes remaining patients, including those with the t(11;14)(q13;q32) and none of the aforementioned abnormalities.