1/2. Giant cell fibroblastoma in a child misdiagnosed as a dermatofibroma.We report a 9-year-old African-American boy with a giant cell fibroblastoma of the shoulder that was incorrectly diagnosed as a keloid and dermatofibroma. Initial misdiagnosis led to a delay of 4 years in the correct diagnosis, with the tumor producing significant local destruction. We review herein the clinical manifestations, histologic findings, histogenesis, relationship to dermatofibrosarcoma protuberans (DFSP), treatment, and differential diagnosis of giant cell fibroblastoma (GCF). This information is important in correctly diagnosing this uncommon, benign, but locally aggressive and recurrent tumor of childhood. The clinician should consider GCF and DFSP when the pathologic diagnosis of dermatofibroma is made in lesions more than 2 cm in diameter, or when this diagnosis is made in a prepubertal child.- - - - - - - - - - ranking = 1keywords = dermatofibroma (Clic here for more details about this article) |
2/2. Dermatomyofibroma: additional observations on a distinctive cutaneous myofibroblastic tumour with emphasis on differential diagnosis.Following the very recent description of a benign plaque-like myofibroblastic tumour of the skin, known as dermatomyofibroma, we present four further cases, emphasizing its clinical features and its histological differential diagnosis. Three patients were adult females and one was a boy. Two of the lesions arose on the anterior abdominal wall, one on the shoulder, and one on the neck. Clinically, there was often close resemblance to a keloid. Follow-up revealed no evidence of recurrence after simple excision. Histologically, these were non-encapsulated but well-circumscribed, plaque-like lesions located in the reticular dermis, and composed of fascicles of monomorphic myofibroblasts, orientated parallel to the skin surface. Immunohistochemically, most of the tumour cells expressed alpha-smooth-muscle actin. The principal differential diagnosis is plaque-stage dermatofibrosarcoma protuberans. Other differential diagnoses include diffuse neurofibroma, dermatofibroma and other myofibroblastic skin tumours.- - - - - - - - - - ranking = 0.16666666666667keywords = dermatofibroma (Clic here for more details about this article) |