title: Testicular seminoma after the complete remission of extragonadal yolk sac tumor : a case report.
abstract: BACKGROUND
  Between 2% and 5% of malignant germ-cell tumors in men arise at extragonadal sites. Of extragonadal germ cell tumors, testicular carcinoma in situ (CIS) are present in 31-42% of cases, and CIS are reported to have low sensitivity to chemotherapy in spite of the various morphology and to have a high likelihood of developing into testicular tumors. A testicular biopsy may thus be highly advisable when evaluating an extragonadal germ cell tumor.
  
  
  METHODS
  A 36-year-old man was diagnosed as having an extragonadal non-seminomatous germ cell tumor, that was treated by cisplatin-based chemotherapy, leading to a complete remission. In the meantime, testicular tumors were not detected by means of ultrasonography. About 4 years later, a right testicular tumor was found, and orchiectomy was carried out. Microscopically, the tumor was composed of seminoma.
  
  
  CONCLUSIONS
  We herein report a case of metachronous occurrence of an extragonadal and gonadal germ cell tumor. In the evaluation of an extragonadal germ cell tumor, a histological examination should be included since ultrasonography is not sufficient to detect CIS or minute lesions of the testis.
authors.affiliation: Department of Urology, Saitama Medical School, Moroyama, Saitama, Japan. veq01625@saitama-med.ac.jp
authors.forename: Isao
authors.initials: I
authors.lastname: Kuroda
authors.forename: Munehisa
authors.initials: M
authors.lastname: Ueno
authors.forename: Tomoko
authors.initials: T
authors.lastname: Mitsuhashi
authors.forename: Ken
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Yanaihara
authors.forename: Takuji
authors.initials: T
authors.lastname: Tsukamoto
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Deguchi
mesh_terms: D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001761:Bleomycin / Q000008:administration & dosage; D002945:Cisplatin / Q000008:administration & dosage; D018240:Endodermal Sinus Tumor / Q000188:drug therapy*; D005047:Etoposide / Q000008:administration & dosage; D006801:Humans; D008297:Male; D016609:Neoplasms, Second Primary / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery; D009919:Orchiectomy; D012074:Remission Induction; D018239:Seminoma / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery; D013736:Testicular Neoplasms / Q000188:drug therapy* / Q000209:etiology* / Q000601:surgery; D014463:Ultrasonography
chemical_list: D001761:Bleomycin; D005047:Etoposide; D002945:Cisplatin