Question: What is (are) Non-involuting congenital hemangioma ?
Answer: Non-involuting congenital hemangioma (NICH) is a rare type of infantile hemangioma, which is a tumor that forms from the abnormal growth of blood vessels in the skin. NICH looks like an oval, purplish mark or bump that can occur on any part of the body. NICH is present from birth (congenital) and increases in size as the child grows. Unlike other hemangiomas, NICH do not disappear spontaneously (involute).
Source: GARD

Question: How to diagnose Non-involuting congenital hemangioma ?
Answer: How is non-involuting congenital hemangioma diagnosed? Non-involuting congenital hemangioma (NICH) is diagnosed by taking a biopsy of the skin mark and examining the tissue under a microscope. NICH looks different under the microscope than most infantile hemangiomas because the blood vessels are arranged more irregularly. Also, the cells in an NICH do not have glucose receptors, whereas the cells of almost all hemangiomas do have glucose receptors. Finally, NICH is different from more common types of hemangiomas because NICH does not spontaneously disappear (involute). Instead, NICH remains stable over time.
Source: GARD

Question: What are the treatments for Non-involuting congenital hemangioma ?
Answer: How might non-involuting congenital hemangioma treated? Because non-involuting congenital hemangioma (NICH) is quite rare, there are no established guidelines for the treatment of this condition. However, the authors of one article on NICH suggest that there is no risk for excessive bleeding during the removal of an NICH and it is unlikely to regrow after surgery. Because NICH is a benign skin mark, surgery isn't necessary but can be considered to improve appearance of the skin.
Source: GARD