Choose the Defensible Next Action

For this case, route the complete evidence set through the current controlled classification procedure for qualified hematopathology review while ensuring that documented mimics are addressed. A smear alone does not establish MDS. The worksheet alone does not assign an SF3B1 or del(5q) subtype because classification requires the controlled criteria review.

Blast interpretation is especially bounded. WHO retains MDS-IB1 at 5-9% marrow blasts or 2-4% peripheral blood blasts, and MDS-IB2 at 10-19% marrow blasts or 5-19% peripheral blood blasts, with Auer rods also supporting MDS-IB2. ICC calls a cytopenic myeloid neoplasm with 10-19% blasts and no AML-defining genetic abnormality MDS/AML. Sampling and subjective assessment can affect blast enumeration, and different platforms can be discordant.

Clonal cytopenia of undetermined significance (CCUS) means unexplained persistent cytopenia with clonality that does not meet criteria for a defined myeloid neoplasm. A single myeloid-associated mutation may fit clonal hematopoiesis or CCUS rather than MDS. When evidence is incomplete, release the measured findings and route the unresolved classification question for qualified review.