Version June 2024
| Condition | Age at onset | Location | Clinical | Histopathology | Immunohistochemistry |
| Plaque-like myofibroblastic tumor | Infancy and early childhood | Lower back, hip; less commonly the upper back | Large, indurated plaque (2 to 9 cm reported), may present with ulceration | Nodular proliferation of spindle cells in short fascicles and disorganized in the dermis and superficial subcutis with thickened collagen bundles and periphery and overlying epidermal acanthosis and basilar hyperpigmentation | Positive for factor XIIIa and SMA; negative for S-100 and CD34 |
| Dermatofibroma | Young adults, rare in first year of life | Lower extremities; less commonly the upper extremities | Less than 1 to 2 cm, flesh-colored to slightly hyperpigmented, firm papules or nodules | Nodular proliferation of spindle cells in fascicles and haphazard in the dermis with peripheral collagen balls | Positive for factor XIIIa; negative for CD34; variable for SMA |
| Dermatomyofibroma | Adolescents and young adults, predominantly female | Neck, arms, upper trunk | 1 to 2 cm, firm, red-brown plaques or nodules | Myofibroblastic fascicles running parallel to epidermis with collagen bundles thinner than surrounding dermis | Positive for vimentin; variable for SMA; negative for desmin, CD34, and S-100 |
| Infantile myofibroma or myofibromatosis | 60% at birth, 80% in first 2 years of life | Head, neck, trunk, upper extremities | 0.5 to 7 cm, skin-colored to vascular-appearing, rubbery to hard nodules | Interlacing fascicles of spindled fibroblasts with minimal cytologic atypia in a pale, collagenous background and foci of hemangiopericytoma-like, vascular pattern; may see focal necrosis and calcification | Positive for vimentin and actin |
| Fibrous hamartoma of infancy | First 2 years of life, up to 20% at birth | Axilla, shoulders, upper chest wall | Solitary, lumpy, 2 to 5 cm nodule | Well-defined fascicles of fibroblasts in collagenous stroma, mature adipose tissue and mixed mesenchymal tissue in a basophilic matrix within subcutis and musculoaponeurotic tissues | |
| Infantile digital fibromatosis (inclusion body fibromatosis) | Infancy, one-third at birth | Digits | Asymptomatic, <3 cm, firm, smooth, pink nodule on lateral or dorsal aspect of digit with deformity of affected digit | Sheets of uniform, spindled fibroblasts in densely collagenous stroma in dermis and subcutis; fibroblasts have characteristic eosinophilic, intracytoplasmic inclusions with clear halo | Positive for actin, desmin, vimentin, and keratin |
| Desmoid-type fibromatosis | Children, up to 30% in first year of life | Head, neck, extremities, shoulder girdle, trunk, hip | Deep-seated, firm, slow-growing, poorly circumscribed mass that can be locally aggressive with infiltration of adjacent muscle, bone, and tendons | Bundles of slender, uniform, spindle cells surrounded by variable amounts of collagen with abundant slit-like vessels; may see keloid-like collagen and variable cellularity | |
| Dermatofibrosarcoma protuberans | 3rd to 5th decade, congenital rare | Trunk, proximal extremities | Firm, protuberant, brown to bluish-red nodules; infantile form presents as atrophic plaque with surrounding bluish discoloration, with proliferation into deep dermis and subcutis causing nodules on a plaque-like surface | Spindle cells in uniform storiform pattern, infiltrates into subcutaneous fat | Positive for CD34 and vimentin; negative for factor XIIIa, S-100, EMA, and SMA |
| Giant-cell fibroblastoma | Children, most <10 years old, male predominance | Back, proximal lower extremities | Solitary, asymptomatic, skin-colored, dermal to subcutaneous, slow-growing, protuberant nodule | Hypocellular dermal and subcutaneous proliferation of spindle cells and pleomorphic multinucleated giant cells in parallel fascicles and honeycomb pattern with myxoid change, irregular pseudovascular spaces lined by giant cells, and perivascular onion skin-like lymphocytic infiltrate; intralesional hemorrhage common near fascia | Positive for CD34; negative for SMA, desmin, keratin, and S-100 |
آیا می خواهید مدیلیب را به صفحه اصلی خود اضافه کنید؟
