Fibrous hamartoma of infancy is a rare, benign, hamartomatous soft tissue tumor that appears within the first 2 years of life. It presents as a painless solitary nodule, tumor, or plaque that is commonly located on the trunk or arms, especially in the axillary, shoulder, or pubic region. Male infants are affected more frequently than female infants.

Fibrous hamartoma may be congenital, and most reported cases were noted in the first year of life. Slow growth up to the age of 5 years is typical, and a few cases have shown spontaneous regression. Rarely, multiple lesions are present.

In a recent study of 145 cases, 2 cases were found to have sarcomatous features histopathologically. The clinical significance of this phenomenon is not yet clear.