Morphological variations of two cases of maxillary myofibromas

Abstract

The aim of this case report is to depict the varied spectrum of clinical presentation of two cases of solitary myofibromas, one of which was intra-osseous whilst the other presented as a soft tissue lesion. This highlights the spectrum of the clinical presentation of the same pathology. In the most recent World Health Organisation (WHO) 2022 classification of soft tissue tumours, myofibroma is included under the category of myopericytomas. Myopericytoma is a distinctive perivascular myoid neoplasm that forms a morphological spectrum with myofibroma. Molecular evidence has revealed PDGFRB (platelet-derived growth factor receptor beta) mutations in myopericytoma and myofibroma as well as SRF-RELA gene fusions in both lesions confirming a common pathogenesis for both.1 Myofibromas are benign soft tissue neoplasms derived from myofibroblastic cells.2 The term myofibroma refers to a solitary lesion. Myofibromatosis refers to cases in which multiple lesions are present which may affect either one or multiple anatomical locations. Myofibromatosis is almost exclusively seen in young children under the age of 2-years. Myofibromas exhibit a wide age range of clinical presentation and may be present at birth or arise within the first two years of age, but may also present in adults with a significant male predominance. Solitary myofibromas have a predilection to occur in the oral cavity, skin or subcutis of the head, neck and trunk.