title: Impact of post-therapy positron emission tomography on prognostic stratification and surveillance after chemoradiotherapy for cervical cancer.
abstract: BACKGROUND
  A study was undertaken to investigate the detection of relapse and survival outcomes in patients with cervical cancer treated with curative intent chemoradiotherapy, and evaluated with a post-therapy (18) F-fluorodeoxyglucose positron emission tomography (FDG-PET) scan.
  
  
  METHODS
  Between January 2002 and June 2007, 105 consecutive patients were prospectively enrolled into a registry study designed to assess outcomes of chemoradiotherapy. A FDG-PET scan was performed between 3 and 12 months (median, 4.9 months) post-treatment at clinician discretion. Tumor response was graded as complete metabolic response, partial metabolic response, or progressive metabolic disease.
  
  
  RESULTS
  Median follow-up was 36 months. At post-therapy FDG-PET, 73 (70%) patients had complete metabolic response, 10 (9%) had partial metabolic response, and 22 (21%) had progressive metabolic disease. Overall survival at 3 years was 77% in all patients, and 95% for those with complete metabolic response. On multivariate analysis, complete metabolic response (P < .0001) and pretreatment tumor volume (P = .041) were strong predictors for overall survival. The number of involved lymph nodes (P < .005) and International Federation of Gynecology and Obstetrics stage (P = .04) were predictive of relapse-free survival. In total, 18 patients relapsed at a single site, and 13 underwent salvage, with a 3-year survival of 67%. Patients with complete metabolic response had a distant failure rate 36-fold less than those with partial metabolic response (P < .0001). After complete metabolic response, only 1 patient (1.6%) relapsed without symptoms and was detected through physical examination.
  
  
  CONCLUSIONS
  The presence of a complete metabolic response at post-therapy FDG-PET is a powerful predictor for survival after chemoradiation. The very low rate of recurrence in patients with a complete metabolic response justifies a conservative follow-up approach for these patients, because relapse is usually symptomatic and not detected by routine clinical review.
authors.affiliation: Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne, Australia. shankar.siva@petermac.org
authors.forename: Shankar
authors.initials: S
authors.lastname: Siva
authors.forename: Alan
authors.initials: A
authors.lastname: Herschtal
authors.forename: Jessica M
authors.initials: JM
authors.lastname: Thomas
authors.forename: David M
authors.initials: DM
authors.lastname: Bernshaw
authors.forename: Suki
authors.initials: S
authors.lastname: Gill
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Hicks
authors.forename: Kailash
authors.initials: K
authors.lastname: Narayan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003131:Combined Modality Therapy; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011379:Prognosis; D012008:Recurrence; D016019:Survival Analysis; D002583:Uterine Cervical Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000401:mortality / Q000532:radiotherapy*
chemical_list: D019788:Fluorodeoxyglucose F18