title: Treatment outcome and patterns of relapse following adjuvant carboplatin for stage I testicular seminomatous germ-cell tumour: results from a 17-year UK experience.
abstract: BACKGROUND
  Following inguinal orchidectomy, management options for patients with stage I seminoma include initial surveillance or treatment with adjuvant radiotherapy or chemotherapy. The anticipated relapse rate for patients followed by surveillance alone is ∼15%, with adjuvant treatment this risk is reduced to ∼4%-5% at 5 years. After carboplatin treatment, follow-up strategies vary and there are no validated, predictive markers of relapse.
  
  
  METHODS
  We conducted a retrospective analysis of all patients presenting with stage I seminoma who received a single cycle of adjuvant carboplatin in South Central England between 1996 and 2013. We report on outcome and the results of univariate and multivariate analysis evaluating possible risk factors for post carboplatin relapse.
  
  
  RESULTS
  A total of 517 eligible patients were identified. All underwent nuclear medicine estimation of glomerular filtration rate before treatment with carboplatin (dosed at area under the curve × 7). With a median follow-up of 47.2 months (range 0.4-214 months), 21/517 patients have relapsed resulting in a 5-year estimated relapse-free survival of 95.0% (95% confidence interval 92.8% to 97.3%). Median time to relapse was 22.7 months (range 12.5-109.5 months). Relapse beyond 3 years was rare (4/517; 0.8%). Twenty of 21 (95%) relapsed patients had retroperitoneal lymph node metastases. The majority (16/21; 76%) of patients had elevated tumour markers at relapse. Twenty of 517 (3.9%) patients developed a new contralateral testicular germ-cell cancer. There were no seminoma-related deaths. Tumour size was the only variable significantly associated with an increased risk of relapse.
  
  
  CONCLUSIONS
  Overall results for this large cohort of patients confirm an excellent prognosis for these patients with outcomes equivalent to those seen in prospective clinical trials. Increasing tumour size alone appears to be associated with an increased risk of post chemotherapy relapse.
authors.affiliation: Cancer Sciences Unit, University of Southampton Faculty of Medicine, Southampton; NIHR Wellcome Trust Clinical Research Facility, University of Southampton, Southampton; Department of Medical Oncology, University Hospital Southampton NHS Foundation Trust, Southampton, UK.
authors.forename: C
authors.initials: C
authors.lastname: Chau
authors.affiliation: Department of Medical Oncology, Kantonsspital Graubünden, Chur.
authors.forename: R
authors.initials: R
authors.lastname: Cathomas
authors.affiliation: Department of Medical Oncology, University Hospital Southampton NHS Foundation Trust, Southampton, UK.
authors.forename: M
authors.initials: M
authors.lastname: Wheater
authors.affiliation: Swiss Group for Clinical Cancer Research Coordinating Center, Bern.
authors.forename: D
authors.initials: D
authors.lastname: Klingbiel
authors.affiliation: Department of Medical Oncology, Kantonsspital St Gallen Hospital, St Gallen, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Fehr
authors.affiliation: Dorset Cancer Centre, Poole Hospital NHS Foundation Trust, Poole.
authors.forename: J
authors.initials: J
authors.lastname: Bennett
authors.affiliation: Department of Histopathology, University Hospital Southampton NHS Foundation Trust, Southampton, UK.
authors.forename: H
authors.initials: H
authors.lastname: Markham
authors.affiliation: Cancer Sciences Unit, University of Southampton Faculty of Medicine, Southampton; Department of Medical Oncology, University Hospital Southampton NHS Foundation Trust, Southampton, UK.
authors.forename: C
authors.initials: C
authors.lastname: Lee
authors.affiliation: Cancer Sciences Unit, University of Southampton Faculty of Medicine, Southampton; Department of Medical Oncology, University Hospital Southampton NHS Foundation Trust, Southampton, UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Crabb
authors.affiliation: Dorset Cancer Centre, Poole Hospital NHS Foundation Trust, Poole. Electronic address: tom.geldart@rbch.nhs.uk.
authors.forename: T
authors.initials: T
authors.lastname: Geldart
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D016190:Carboplatin / Q000627:therapeutic use*; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy / Q000473:pathology* / Q000532:radiotherapy; D009367:Neoplasm Staging; D009373:Neoplasms, Germ Cell and Embryonal / Q000188:drug therapy* / Q000601:surgery; D009919:Orchiectomy; D012189:Retrospective Studies; D018239:Seminoma / Q000188:drug therapy* / Q000601:surgery; D013736:Testicular Neoplasms / Q000188:drug therapy* / Q000601:surgery; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000970:Antineoplastic Agents; D016190:Carboplatin
keywords: adjuvant carboplatin; chemotherapy; relapse pattern; stage I seminoma; treatment outcome