Fig. 1.
a A new risk model for systemic mastocytosis (SM) that does not include World Health Organization (WHO) class assignment or genetic information (n = 380); risk factors: i) age >60 years (2 points), ii) platelets <150 × 109/l (2 points), iii) anemia below sex-adjusted normal (2 points), iv) serum alkaline phosphatase above normal range (1 point), and v) serum albumin <3.5 g/dl (1 point). b The same group of 380 patients stratified by the Mayo Alliance Prognostic System, which includes WHO class assignment; risk factors: i) age >60 years, ii) platelets <150 × 109/l, iii) anemia below sex-adjusted normal, iv) serum alkaline phosphatase above normal range, and v) advanced vs indolent/smouldering SM. c Distribution of adverse mutations among the new WHO class-independent risk categories. d Distribution of formal WHO categories of SM among the new WHO class-independent risk categories: ISM indolent SM, includes smouldering SM, ASM aggressive SM, SM-AHN SM associated with another non-mast cell hematologic neoplasm