In SM patients in whom <2 B findings and no C finding are detected (category A), the diagnosis of ISM can be established. When ≥2 B findings but no C findings are present, the diagnosis is SSM, and when one or more C findings (+/− B findings) are detected, the final diagnosis is either ASM (<20% MCs in BM smears) or MCL (MCs ≥20% on marrow smears; see also Table 1).

CT indicates computed tomography; ANC, absolute neutrophil count; Hb, hemoglobin; PLT, platelets.