Cellular angiofibroma is a rare benign tumor that has been described in several case studies in children and adults. In terms of the genital and pelvic regions, it is most associated with the labium and vulvovaginal areas in females, and superficially in the scrotum and inguinal canal in males. Cellular angiofibromas have been described in the nasopharynx as well as the female and male genital regions [9, 12, 13]. In 1998 Laskin et al. reviewed angiomyofibroblastomas in the male genital region with six scrotal cases and five inguinal cases. These tumors were superficially located and well circumscribed. After simple excision, one of seven patients on follow up demonstrated recurrent/persistent disease. CAF have been described as more common in women as demonstrated by Mandata et al when they gathered 79 cases of CAF in women from 1997 to 2014. They found that 56% of these CAF cases showed tumor growth in the vulvovaginal and labium region. Similarly, most male cases have been described in analogous male genitalia such as the scrotum and inguinal regions. Unusual location of cellular angiofibroma has been also described in the prostate in a male patient [14].

The diagnosis of cellular angiofibroma can be challenging especially when suspected malignancy is necessary to be ruled out. Valuable information is often provided by MR imaging, especially when ultrasound and/or clinical examinations are inconclusive [15]. Combining conventional and functional magnetic resonance data provides useful diagnostic information in the preoperative characterization of scrotal masses [16]. Generally, diagnosis of CAF is established with biopsy proven pathological examination and immunohistochemical staining. Grossly, CAF presents as a well circumscribed mass without a capsule and often involves superficial tissues. Microscopic images demonstrate bland spindle shaped cells with fusiform nuclei and pale eosinophilic cytoplasm with wispy collagen bundles in the extracellular matrix. Small to medium sized thick walled hyalinized vessels and scattered adipose tissue are also characteristic of the tumor. Cellular atypia and necrosis are uncommon. Sarcomatous transformation in a cellular angiofibroma is reported in only one rare case [17]. Immunohistochemistry findings specific the tumor cells include vimentin, CD99, CD 34, ER/PR, and desmin.

These tumors contain two principle components: the cellular spindle stromal cells and the prominent thick-walled hyalinized blood vessels [18]. The differential diagnosis of this unique tumor includes angiomyofibroblastoma, spindle cell lipoma, solitary fibrous tumor, leiomyoma and aggressive angiomyxoma. CAF is a mesenchymal neoplasm that falls in the spectrum of angiomyofibroblastoma, a well circumscribed less cellular benign neoplasm, and aggressive angiomyxoma, which can be a fast growing locally infiltrative tumor with a tendency to recur when incompletely excised. Angiomyofibroblastoma, cellular angiofibroma, and aggressive angiomyxoma can be distinguished via histologic appearance, immunohistochemistry staining, and the clinical findings. All published cases recommend close follow up of lesions and in the case of rapid increase in size, prompt surgical excision of mass with negative margins is appropriate with the goal of preventing recurrence [19]. In 2013, Emtage et al. described a case of a middle-aged man with voiding symptoms and a large rapidly growing 13.5 cm cellular angiofibroma of male pelvis. This team elected simple surgical resection, but there was no report on follow up to track recurrence or metastasis. A recent case report from Kumar et al in 2018 described a female periurethral mass that had been enlarging to 2-3 cm over 8 years. Simple surgical excision of this mass resulted in cure with no signs of recurrence in the 2 years follow up period.