[Giant cell fibroblastoma. A rare soft tissue tumor in childhood]

We report on a 9-year-old girl with a giant cell fibroblastoma of the right anterior chest wall. This rare soft tissue tumour occurs predominantly in the first two decades of life. The typical clinical presentation is a solitary, usually 2-6 cm large, non-tender mass of blue-greyish colour which is mostly located on the back, anterior chest wall, thigh or groin. The histology shows a loose infiltrate of predominantly bland spindle cells in dermis and subcutis. Characteristic elements of the tumour are large angiectoid branching spaces lacking any endo- or epithelium, and relatively small multinucleated cells (floret cells). The recurrence rate is high if the tumour is not excised with adequate safety margins. Metastases are not reported. It is of pre-eminent importance to differentiate this rare benign tumor from sarcomas, in order to avoid an inappropriately aggressive therapy.