Fibrous Pseudotumor of the Epididymis: Case Report and Literature Review

Author(s): Giovanni Vitor Garabini, Matheus Naves Rosa, Fernando Aparecido Pazini, Guilherme Ribeiro de Mendonça Gonçalves Da Silva, Daniel Salermo Muzilli, Mateus Santos Matos, Laiane Milani de Arruda, Victor Augusto Belani Fernandes, Thiago da Silveira Antoniassi

Fibrous paratesticular pseudotumor is a rare benign condition that can mimic scrotal neoplasms and lead to unnecessary orchiectomy. We report a 21-year-old man who presented with acute right hemiscrotal pain and swelling. Ultrasound showed a solid extratesticular hyperechoic nodule in the tail of the right epididymis with preserved testicular vascularity, and pelvic magnetic resonance imaging demonstrated a circumscribed lesion that was hypointense on T2-weighted sequences, without diffusion restriction, and with post-contrast enhancement—features consistent with fibrous proliferation. Testis-sparing local excision was performed and histopathology confirmed a fibrous pseudotumor of the epididymis. A brief literature review is provided, emphasizing the role of MRI and intraoperative frozen section to avoid orchiectomy, the possible association with IgG4-related disease in a subset of patients, and the excellent prognosis after complete excision.

Fibrous Pseudotumor, Epididymis, Paratesticular Mass, Igg4-Related Disease, Testis-Sparing Surgery

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