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
Refractory thrombocytopenia is characterized by >10% dysplastic megakaryocytes of at least 30 megakaryocytes.
(This code is effective for cases diagnosed 2010 and later. For cases diagnosed prior to 2010, see code 9989/3.)
Thrombocytopenia is an abnormal drop in the number of platelets which are involved in forming blood clots. Distinction between Refractory thrombocytopenia and other chronic autoimmune thrombocytopenia is critical and may be extremely difficult clinically and morphologically. Cytogenetic studies may be of considerable aid in this distinction. Cytogenetic abnormalities may be found in up to 50% of cases.
For MDS diseases (9980, 9982, 9983, 9985, 9986, 9989, 9991, 9992), abstracting each of the subtypes would result in over-counting of the diseases. 1. Code only the first subtype that is diagnosed. 2. Do not change the histology code or create a new abstract for any subsequent specific MDS subtypes.