Mastocytosis: Statistics

Approved by the Cancer.Net Editorial Board, 01/2021

ON THIS PAGE: You will find information about the number of people who are diagnosed with mastocytosis each year. Use the menu to see other pages.

Mastocytosis is a rare disorder, and its true incidence rates are unknown. One research study estimates that 1 in 10,000 people in the United States have this disease. Mastocytosis generally affects males and females in equal numbers. The disease can begin during childhood or adulthood.

When it occurs in childhood, mastocytosis usually starts within the first 2 years of a child’s life. Approximately 80% of childhood cases are diagnosed during the first year of a child’s life. Most of those cases only involve the skin. In adults, most cases involve the entire body, with fewer than 5% of cases limited to the skin.

It is important to remember that statistics on mastocytosis are an estimate. The estimate comes from data based on the number of people with mastocytosis in the United States. Talk with your doctor if you have any questions about this information.

Statistics adapted from the websites of the National Institute of Health’s Genetic and Rare Diseases Information Center and the National Organization for Rare Disorders (sources accessed January 2021).

The next section in this guide is Risk Factors. It explains what factors may increase the chance of developing mastocytosis. Use the menu to choose a different section to read in this guide.