title: Prostatic Stromal Tumor of Uncertain Malignant Potential Which Was Difficult to Diagnose.
abstract: Here, we report a case of stromal tumor of uncertain malignant potential (STUMP) that was difficult to diagnose. A 53-year-old male was found to have a hard nodule on digital rectal examination; magnetic resonance imaging revealed a large nodule on the left side of the prostate, indicating prostate cancer. However, pathological diagnosis of the biopsy specimen was benign prostatic hyperplasia. Although a papillary tumor in the prostatic urethra was also seen on urethrocystoscopy, the tumor specimen obtained from transurethral resection was not malignant. The tumor in the prostatic urethra recurred only 3 months after transurethral resection, and pathological findings revealed benign hyperplasia not only in the stromal tissue but also in the epithelium; therefore, the prostate tumor was suspected to be STUMP. It took many prostate pathologists a long time to reach the final diagnosis of STUMP. STUMP is a rare benign tumor, difficult to diagnose, and sometimes transforms into stromal sarcoma. Thus, we should consider radical resection in such cases.
authors.affiliation: Department of Urology, Toyama Prefectural Central Hospital, 2-2-78 Nishinagae, Toyama, Toyama 930-8550, Japan.
authors.forename: Satoko
authors.initials: S
authors.lastname: Matsuyama
authors.affiliation: Department of Urology, Toyama Prefectural Central Hospital, 2-2-78 Nishinagae, Toyama, Toyama 930-8550, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nohara
authors.affiliation: Department of Urology, Toyama Prefectural Central Hospital, 2-2-78 Nishinagae, Toyama, Toyama 930-8550, Japan.
authors.forename: Shohei
authors.initials: S
authors.lastname: Kawaguchi
authors.affiliation: Department of Urology, Toyama Prefectural Central Hospital, 2-2-78 Nishinagae, Toyama, Toyama 930-8550, Japan.
authors.forename: Chikashi
authors.initials: C
authors.lastname: Seto
authors.affiliation: Department of Pathology, Toyama Prefectural Central Hospital, 2-2-78 Nishinagae, Toyama, Toyama 930-8550, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Nakanishi
authors.affiliation: Department of Pathology, Toyama Prefectural Central Hospital, 2-2-78 Nishinagae, Toyama, Toyama 930-8550, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Uchiyama
authors.affiliation: Department of Pathology, Toyama Prefectural Central Hospital, 2-2-78 Nishinagae, Toyama, Toyama 930-8550, Japan.
authors.forename: Shin
authors.initials: S
authors.lastname: Ishizawa
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