Hemangioendothelioma and Kasabach-Merritt Syndrome
A Kaposiform hemangioendothelioma (KHE) is a rare, benign tumor that mostly affects infants. These tumors tend to destroy platelets (the blood cells responsible for blood clotting). When KHE destroys your platelets, we call the condition Kasabach-Merritt syndrome.
KHE and Kasabach-Merritt syndrome usually appear in the first three months of life. First, we see a raised area without or with red or purple discoloration of the skin. This area typically enlarges suddenly and becomes dark purple due to bleeding into the soft tissues. If the baby’s blood platelet count is low, we may see multiple tiny red spots on the skin (petechiae).
At Mount Sinai, we can usually diagnose KHE visually and with bloodwork. Often, we perform a magnetic resonance imaging test to confirm the diagnosis.
We treat KHE and Kasabach-Merritt Syndrome with steroids to stop the tumors from forming new blood vessels (angiogenesis). We usually prescribe a pill. If pills don’t work, we try intravenous treatment. If this does not treat the condition, we may use multiple medications. About half of all babies with KHE respond well to drug treatment.
For the other 50 percent, we may use embolization or sclerotherapy to help shrink the tumor and restore a normal platelet count. We may also surgically remove the tumor. We rarely give platelet transfusions because these can stimulate growth of the tumor. Infants who do not respond to treatment could have very serious bleeding (hemorrhage).
KHE rarely disappears completely. Most children have a small area of skin discoloration. In rare cases, the tumor can recur later in life.