Cutaneous changes in fibrous hamartoma of infancy
A 4-month-old healthy white boy infant was brought to the dermatology clinic. His mother noticed a rapidly enlarging on the child's upper back on month before admission. Physical examination revealed the presence of 2 × 4 cm well-circumscribed, firm mass with a hairy and altered pigmentation on the upper back. The solitary lesion was firm, adherent to underlying tissue and had grown in the last 2 weeks. No family history of cutaneous abnormalities was elicited from the mother.\nExcisional biopsy of the mass was performed. Grossly it was poorly circumscribed but hairy with firm gray-white tissue fixed to the underlying subcutaneous plane.\nHistologically, the lesion was centred in the deep dermis although reached the papillary dermis and the cutaneous appendages. It was composed of three different mesenchymal tissues: Well-defined intersecting trabecule of fibrous tissue of varying size and shape, loosely textured areas consisting chiefly of immature small, round or stellate cells in a myxoid matrix, and varying amounts of mature fat.\nAlso the included overlying skin contained foci of eccrine hyperplasia with pronounced duct ectasia, dilated lumens with complex papillary formations and squamous metaplasia. This abnormal eccrine glands was surrounded mainly by the primitive mesenchymal tissue component of FHI []. Also it showed the formation of anomalous hair structures in the overlying epidermis, with microfollicles and abortive hair follicles [].