As previously suggested for mammary and extra-mammary myofibroblastoma [16], it is likely that the morphological variations in cellular (small spindled/stellate versus eloganted fibroblastic-like cells) and stromal composition (myxoid versus fibrosclerotic) reflect the plasticity of the neoplastic cells in adopting a myofibroblastic or fibroblastic profile (vimentin+/desmin-/-smooth muscle actin-) in response to various stimuli, including hormonal, genetic and microenviromental stimuli, that still remain to be elucidated. The gene discussed is VIM; the disease is myofibroblastoma.