Hamartoma fibrosis of childhood D23 L

Rare, solitary, usually congenital, or acquired in the first year of life (rarely later), complex malformation belonging to infantile fibromatoses, in which mature fibrous and lipomatous tissue mixes with immature, mesenchymal parts (spindle cells and myxoidal stroma).

Mostly congenital or occurring in the course of the 1st year of life; boys are 3 times more frequently affected than girls.

Torso and buttocks (about 70%), extremities (25%), head and neck (3-5%)

Solitary, firm, non-polent, subcutaneous, skin-coloured, 0.5-9.0 cm large lump, often present at birth.

Overlying skin is often hypertrichotic.

Occasionally the fibrous hamartoma of childhood also occurred in congenital melanocytic nevi.

In addition to mature adipocytes, immature mesenchymal cells in a myxoid stroma interspersed with connective tissue strands. There is reactivity for CD34, S-100 protein. The proliferation factor Ki-67 is increased in the mesenchymal parts.

• In the case of very large, slightly regressing nodes, the node should be excised without a large safety margin.
• Some authors recommend excision as a matter of principle.
• Remark: Finally, the diagnosis is only histologically verified.

Hamartoma tends to spontaneous regression.

1. Melnick L et al (2015) Fibrous Hamartoma of Infancy: A Firm Plaque Presenting with Hypertrichosis and Hyperhidrosis. Pediatric Dermatol 32:533-535
2. Müller CS et al.(2015) Fibrous hamartoma of infancy within a congenital nevus. J Dtsch Dermatol Ges 13:1282-1284.
3. Monajemzadeh M et al. (2013) Vulvar fibrous hamartoma of infancy: a rare case report and review of literature. J Low Genit Tract Dis 17:92-94
4. Saab ST et al(2014) Fibrous hamartoma of infancy: a clinicopathologic analysis of 60 cases. On J Surg Pathol 38:394-401
5. Yu G et al(2015) Fibrous hamartoma of infancy: a clinical pathological analysis of seventeen cases. Int J Clin Exp Pathol 8:3374-3377