title: Radiation-induced leiomyosarcoma of the prostate after brachytherapy for prostatic adenocarcinoma.
abstract: Radiation therapy (RTx) has been employed as a curative therapy for prostatic adenocarcinoma. RTx-induced sarcomas (RISs) are rare, late adverse events, representing less than 0.2% of all irradiated patients. RISs are more aggressive tumors than prostatic adenocarcinomas. Herein, we present a case with RTx-induced prostatic leiomyosarcoma after permanent brachytherapy for prostatic adenocarcinoma. A 69-year-old male presented with dysuria and gross hematuria. Six years previously, he had been diagnosed with localized prostate cancer and was treated by permanent brachytherapy. Urethroscopy showed stenosis by a tumor at the prostate. Transurethral prostatectomy was performed for a diagnosis. Based on pathological findings, the diagnosis was leiomyosarcoma of the prostate. He was treated with three cycles of neoadjuvant chemotherapy (CTx) that consisted of doxorubicin and ifosfamide (AI), followed by a prostatocystectomy with intrapelvic lymphadenectomy. The tumor extended from the prostate and infiltrated the bladder wall and serosa with lymphatic and venous invasion. The surgical margin was negative, and no residual prostatic adenocarcinoma was observed. The proportion of necrotic tumor cells by neoadjuvant CTx was around 50%. Subsequently, adjuvant CTx was offered, but the patient chose a follow-up without CTx. Local recurrence and lung metastasis were detected by computed tomography 3 months after the surgery. He was treated again with AI. However, CTx was not effective and he died 6 months after the operation. In conclusion, an effective treatment strategy for prostatic sarcoma should be developed in the near future, although the clinical feature of prostatic sarcoma remains unclear due to its rare incidence.
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan ; Department of Internal Medicine, Higashi Sapporo Hospital, Sapporo, Japan.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Horiguchi
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Kohichi
authors.initials: K
authors.lastname: Takada
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kamihara
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Soushi
authors.initials: S
authors.lastname: Ibata
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Iyama
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Sato
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Hayashi
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Miyanishi
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Rishu
authors.initials: R
authors.lastname: Takimoto
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kobune
authors.affiliation: Departments of Urological Surgery and Andrology, Sapporo, Japan.
authors.forename: Ko
authors.initials: K
authors.lastname: Kobayashi
authors.affiliation: Department of Internal Medicine, Higashi Sapporo Hospital, Sapporo, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hirayama
authors.affiliation: Departments of Urological Surgery and Andrology, Sapporo, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Masumori
authors.affiliation: Departments of Surgical Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Hasegawa
authors.affiliation: Departments of Medical Oncology and Hematology, Sapporo, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Kato
keywords: Brachytherapy; Leiomyosarcoma; Prostatic sarcoma; Radiation-induced sarcoma; p53