SEER is an authoritative source of information on cancer incidence and survival in the United States. SEER currently collects and publishes cancer incidence and survival data from population-based cancer registries covering approximately 28 percent of the U.S. population.
9 - Grade/differentiation unknown, not stated, or not applicable
This leukemia meets the criteria for assignment to both T and myeloid lineage, but in which blast lack geneticabnormalities. Most cases have blasts with no distinguishing features, morphologically resembling ALL, or have dimorphic populations, with one resembling lymphoblasts and the other resembling myeloblasts.
(This code is effective for cases diagnosed 2010 and later. For cases diagnosed prior to 2010, see code 9801/3.)