Fibrous hamartoma of infancy: an experience of a single institute.

Purpose: Fibrous hamartoma (FH) of infancy is a distinctive fibrous growth that most frequently occurs at birth and during the postnatal period. It is important for clinicians and pathologists to recognize this entity to avoid an aggressive approach.

Methods: We herein describe the clinicopathologic features of 9 FHs diagnosed at a single institution between 1997 and 2010.

Results: There were 7 boys and 2 girls, and the mean age of presentation was 14.7 months. The common locations were the lower back and gluteal region (n = 3) and scrotum (n = 2). They were solitary lesions, and measured 1.0 to 7.0 cm in maximum diameter (mean, 4.9 cm). The excised masses tended to be poorly circumscribed, and consisted of an intimate mixture of firm, gray-white tissue with fat. Histologically, these lesions were composed of 3 components forming a vague, irregular, organoid pattern: well-defined intersecting trabeculae of fibrocollagenous tissue; loosely textured areas of small, rounded, primitive mesenchymal cells; and mature fat. Over a median follow-up of 72 months, no patient showed recurrence.

Conclusion: FH should be distinguished from other forms of fibromatosis and malignant tumors because it is benign and usually cured by local excision.