Superficial myofibroblastoma of the lower female genital tract: report of a series including tumours with a vulval location

Aims: To describe the clinical and pathological features of 12 further cases (in 11 patients) of superficial cervicovaginal myofibroblastomas (SCVM), rare tumours that hitherto have been described only in a single series of cases involving the cervix and vagina. Methods and results: The patients' ages ranged from 23 to 80 years. Ten tumours were located in the vagina and two in the vulva. Three patients had been taking tamoxifen. The tumours ranged in size from 2 to 45 mm and morphologically were well-circumscribed lesions composed of bland ovoid to spindle-shaped cells, often with wavy nuclei. These cells were arranged in a variety of architectural patterns and were set in a finely collagenous stroma. Five cases exhibited stromal oedema or myxoid change and in eight cases hyalinized areas with thick, dense collagen bundles were present. Immunohistochemically, there was positivity with vimentin (11 of 11 cases tested), CD34 (six of 12 cases), desmin (nine of 12 cases) and oestrogen receptor (nine of 11 cases). All cases tested were negative for smooth muscle actin, S100, h-caldesmon, HMB45, and CD31. In this study we expand on the morphological spectrum of these rare lesions and reiterate their association with tamoxifen. Conclusions: Since these lesions may occur on the vulva, as well as the cervix and vagina, we propose the term 'superficial myofibroblastoma of the lower female genital tract'.