Cellular pseudosarcomatous fibroepithelial stromal polyp of the vagina during pregnancy: a lesion that is overdiagnosed as a malignant tumor

Abstract

Fibroepithelial stromal polyp (FSP) is a benign lesion that can occur at various sites, including the lower female genital tract. In rare cases, however, it may exhibit hypercellularity, bizarre cytomorphological features, and atypical mitoses resulting in an overdiagnosis as a malignant tumor despite its benign clinical course. Recently, we experienced one case of a 30-year-old pregnant woman with cellular pseudosarcomatous FSP that was initially diagnosed as a malignant fibrous histiocytoma at a primary clinic. In addition to describing the rare features of this case, we wish to increase awareness about this benign lesion which will be essential for avoiding unnecessary radical surgery or chemoradiation treatment.

Keywords: Fibroepithelial polyp; Pregnancy; Vagina.

Fig. 1

Microscopic findings of a cellular pseudosarcomatous fibroepithelial stromal polyp. (A) This fibroepithelial polyp of the vagina shows a single pedunculated mass covered with squamous epithelium. The stromal component shows variable cellularity from area to area. The subepithelial stroma is composed of atypical spindle cells with abundant blood vessels. There are also scattered stellate, bizarre multinucleated giant cells extending into the overlying mucosa. (B) The tumor cells of the pseudosarcomatous area show abundant pale cytoplasm with prominent nucleoli, coarse chromatin, nuclear pleomorphism, and numerous atypical mitoses.

Fig. 2

Immunohistochemical finding of cellular pseudosarcomatous fibroepithelial stromal polyp. The tumor cells show immunopositivity for CD10.