title: Myoid gonadal stromal tumor: a distinct testicular tumor with peritubular myoid cell differentiation.
abstract: We report a distinct, primary testicular tumor with peritubular myoid cell differentiation. A 25-year-old man developed a well-circumscribed testicular tumor composed of cytologically bland spindled cells, which were strongly and diffusely positive for desmin, smooth muscle actin, muscle-specific actin, and smooth muscle myosin. In addition, S-100 was diffusely positive, and cytokeratin (CK5/6 and AE1/3) was focally positive. Calretinin, inhibin, and CD34 were all negative. This pattern of immunoreactivity was very similar to the normal adjacent peritubular myoid cells. Follow-up after radical orchiectomy showed benign behavior. We found reports of 6 similar intratesticular tumors demonstrating peritubular myoid cell-like differentiation and having favorable outcome. We believe that the myoid gonadal stromal tumor is a rare, yet distinct, testicular tumor separate from leiomyoma and deserves recognition.
authors.affiliation: University of California San Diego, San Diego, CA 92103-8720, USA.
authors.forename: Shouying
authors.initials: S
authors.lastname: Du
authors.forename: Jesse
authors.initials: J
authors.lastname: Powell
authors.forename: Anselm
authors.initials: A
authors.lastname: Hii
authors.forename: Noel
authors.initials: N
authors.lastname: Weidner
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D002471:Cell Transformation, Neoplastic; D003937:Diagnosis, Differential; D006801:Humans; D007889:Leiomyoma / Q000175:diagnosis; D008297:Male; D032389:Myocytes, Smooth Muscle / Q000378:metabolism / Q000473:pathology*; D009208:Myoepithelioma / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D012671:Seminiferous Tubules / Q000473:pathology*; D017154:Stromal Cells / Q000378:metabolism / Q000473:pathology; D013736:Testicular Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor