title: Screening for carcinoma in situ in the contralateral testicle in patients with testicular cancer: a population-based study.
abstract: BACKGROUND
  Screening programmes for contralateral carcinoma in situ (CIS) testis in patients with unilateral germ-cell cancer (GCC) have never been evaluated. We investigated the effect of screening for contralateral CIS in a large nation-wide, population-based study.
  
  
  METHODS
  A contralateral single-site biopsy was offered to 4130 patients in whom GCC had been diagnosed in 1984-2007 (screened cohort); 462 patients in whom GCC was diagnosed in 1984-1988 comprised the unscreened cohort. Cases with CIS were offered radiotherapy. Initially CIS-negative biopsies in patients with metachronous GCC were revised according to today's standards. Risk for metachronous GCC was estimated using cumulative incidence and the Cox proportional hazards model.
  
  
  RESULTS
  In the screened cohort, contralateral CIS was found in 181 (4.4%) patients. The cumulative incidence of metachronous GCC after 20 years was 1.9% in the screened cohort and 3.1% in the unscreened cohort (P = 0.097), hazard ratio (HR) for the unscreened cohort: 1.59 (P = 0.144). Expert revision with contemporary methodology of CIS-negative biopsy samples from patients with metachronous cancer revealed CIS in 17 out of 45 (38%) cases. Decreased risks for metachronous GCC were related to older age at diagnosis (HR 0.52 per 10 years, P < 0.001) and chemotherapy (HR 0.35, P = 0.002). Limitations include the small number of patients in the unscreened cohort and the retrospective study design.
  
  
  CONCLUSIONS
  Our evaluation of a national population-based screening programme for contralateral CIS in patients with testicular cancer showed no significant difference in the risk for metachronous GCC between a screened and an unscreened cohort. Single-site biopsy including modern immunohistochemistry does not identify all cases of CIS.
authors.affiliation: Department of Oncology 5073, Copenhagen University Hospital, Rigshospitalet, Copenhagen; Department of Survivorship, Danish Cancer Society Research Center, Copenhagen. Electronic address: maria.gry.gundgaard@regionh.dk.
authors.forename: M G G
authors.initials: MGG
authors.lastname: Kier
authors.affiliation: Department of Oncology 5073, Copenhagen University Hospital, Rigshospitalet, Copenhagen.
authors.forename: J
authors.initials: J
authors.lastname: Lauritsen
authors.affiliation: Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen.
authors.forename: K
authors.initials: K
authors.lastname: Almstrup
authors.affiliation: Department of Oncology 5073, Copenhagen University Hospital, Rigshospitalet, Copenhagen.
authors.forename: M S
authors.initials: MS
authors.lastname: Mortensen
authors.affiliation: Department of Pathology, Copenhagen University Hospital, Rigshospitalet, Copenhagen.
authors.forename: B G
authors.initials: BG
authors.lastname: Toft
authors.affiliation: Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen.
authors.forename: E
authors.initials: E
authors.lastname: Rajpert-De Meyts
authors.affiliation: Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen.
authors.forename: N E
authors.initials: NE
authors.lastname: Skakkebaek
authors.affiliation: Department of Oncology 5073, Copenhagen University Hospital, Rigshospitalet, Copenhagen.
authors.forename: M
authors.initials: M
authors.lastname: Rørth
authors.affiliation: Department of Oncology 5073, Copenhagen University Hospital, Rigshospitalet, Copenhagen.
authors.forename: H
authors.initials: H
authors.lastname: von der Maase
authors.affiliation: Department of Oncology, Aarhus University Hospital, Aarhus.
authors.forename: M
authors.initials: M
authors.lastname: Agerbaek
authors.affiliation: Department of Oncology, Odense University Hospital, Odense.
authors.forename: N V
authors.initials: NV
authors.lastname: Holm
authors.affiliation: Department of Statistics, Danish Cancer Society Research Center, Copenhagen, Denmark.
authors.forename: K K
authors.initials: KK
authors.lastname: Andersen
authors.affiliation: Department of Survivorship, Danish Cancer Society Research Center, Copenhagen.
authors.forename: S O
authors.initials: SO
authors.lastname: Dalton
authors.affiliation: Department of Oncology 5073, Copenhagen University Hospital, Rigshospitalet, Copenhagen; Department of Survivorship, Danish Cancer Society Research Center, Copenhagen.
authors.forename: C
authors.initials: C
authors.lastname: Johansen
authors.affiliation: Department of Oncology 5073, Copenhagen University Hospital, Rigshospitalet, Copenhagen.
authors.forename: G
authors.initials: G
authors.lastname: Daugaard
mesh_terms: D000328:Adult; D002278:Carcinoma in Situ / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D015331:Cohort Studies; D003131:Combined Modality Therapy; D003718:Denmark / Q000453:epidemiology; D055088:Early Detection of Cancer; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D009367:Neoplasm Staging; D009373:Neoplasms, Germ Cell and Embryonal / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D009378:Neoplasms, Multiple Primary / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D011379:Prognosis; D018570:Risk Assessment; D013736:Testicular Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy
keywords: carcinoma in situ; screening programme; testicular cancer