title: JOURNAL CLUB: Value of Quantitative FDG PET/CT Volumetric Biomarkers in Recurrent Colorectal Cancer Patient Survival.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the impact of quantitative PET parameters in the overall survival of patients with recurrent colorectal cancer.
  
  
  METHODS
  A total of 105 patients with a biopsy-proven recurrence of colorectal cancer who underwent PET/CT were included in the study. A gradient segmentation method was used to calculate maximum and peak standardized uptake values (SUVmax, SUVpeak), total lesion glycolysis (TLGtotal), and metabolic tumor volume (MTVtotal). These parameters were measured for each recurrent lesion at the primary, locoregional, and distant sites. The median follow-up time was 31.3 months. Overall survival (OS) was the primary outcome and was calculated using Kaplan-Meier survival plots and Cox regression analyses.
  
  
  RESULTS
  The mean ± SD for SUVmax, SUVpeak, TLGtotal, and MTVtotal of the included patients was 7.3 ± 5.3, 5.3 ± 3.3, 280.8 ± 1181 g, and 79.8 ± 294 mL, respectively. The median OS for patients who were alive was 50 months in comparison with 23.4 months among patients who died. Age (p = 0.041), tumor grade (p = 0.010), median TLG (p = 0.031), and median MTV (p = 0.009) remained significantly associated with OS in the multivariate Cox regression analysis. Kaplan-Meier survival analysis performed on the basis of the median PET/CT parametric values showed that SUVmax (threshold, 5.63; hazard ratio [HR] = 1.7; 95% CI, 1-2.8; p = 0.02), MTVtotal (threshold, 13.85 mL; HR = 2.2; 95% CI, 1.3-3.9; p = 0.003), and TLGtotal (threshold, 36.14 g; HR = 1.9; 95% CI, 1.1-3.3; p = 0.01) were significant predictors of OS during follow-up. An integrated risk stratification model with SUVmax and MTVtotal into three subgroups predicted patient survival outcomes (HR = 1.8; 95% CI, 1.25-2.65; log-rank p = 0.003).
  
  
  CONCLUSIONS
  SUVmax, MTVtotal, TLGtotal, and integrated score with FDG avidity and total tumor burden provide survival information for patients with biopsy-proven recurrent colorectal cancer.
authors.affiliation: 1 Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St, JHOC 3235, Baltimore, MD 21287.
authors.forename: Charles
authors.initials: C
authors.lastname: Marcus
authors.affiliation: 1 Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St, JHOC 3235, Baltimore, MD 21287.
authors.forename: Rick
authors.initials: R
authors.lastname: Wray
authors.affiliation: 1 Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St, JHOC 3235, Baltimore, MD 21287.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Taghipour
authors.affiliation: 1 Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St, JHOC 3235, Baltimore, MD 21287.
authors.forename: Wael
authors.initials: W
authors.lastname: Marashdeh
authors.affiliation: 1 Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St, JHOC 3235, Baltimore, MD 21287.
authors.forename: Se Jin
authors.initials: SJ
authors.lastname: Ahn
authors.affiliation: 1 Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St, JHOC 3235, Baltimore, MD 21287.
authors.forename: Esther
authors.initials: E
authors.lastname: Mena
authors.affiliation: 1 Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, 601 N. Caroline St, JHOC 3235, Baltimore, MD 21287.|2 Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, MD.|3 Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD.
authors.forename: Rathan M
authors.initials: RM
authors.lastname: Subramaniam
mesh_terms: D000368:Aged; D001706:Biopsy; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality* / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000401:mortality* / Q000473:pathology*; D009367:Neoplasm Staging; D000072078:Positron Emission Tomography Computed Tomography; D011857:Radiographic Image Interpretation, Computer-Assisted; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D016019:Survival Analysis; D047368:Tumor Burden
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: PET/CT; colorectal cancer; follow-up; metabolic tumor volume; overall survival; recurrence; standardized uptake value; total lesion glycolysis