title: Validation of metabolic tumor volume as a prognostic factor for oral cavity squamous cell carcinoma treated with primary surgery.
abstract: Despite the promise of metabolic tumor volume (MTV) as a risk-stratifying marker, the retrospective design of the initial study limits its generalizability. Therefore, this study sought to validate MTV as a prognostic factor for oral cavity squamous cell carcinoma (OCSCC) treated with primary surgery within an independent data set.
  
  
  
  The validation data set consisted of 42 patients diagnosed with OCSCC between 2008 and 2012. The original cohort consisted of 80 patients. MTV and SUVmax were calculated for the primary tumor and nodal metastasis separately, as well as combined. Before statistical analysis, MTV and SUVmax values were divided into intertertile thirds to allow for intergroup survival analysis. Validation analysis was conducted on the validation data set alone. Data from both cohorts were then combined (n=122) to increase statistical power.
  
  
  
  An increase in combined MTV of 17.5cm(3) was associated with statistically significant increase in risk of disease recurrence (HR=19.2, p<0.001) and death (HR=9.2, p<0.05). Combined SUVmax failed to predict overall (HR=1.0, p>0.05) and disease-free survival (HR=1.0, p>0.05). Increase in the MTV of the primary tumor was associated with an increase in the risk of disease recurrence (HR=21.7, p=0.0001) and risk of death (HR=7.0, p=0.0001), while increase in the MTV of the locoregional neck metastasis was not (p>0.05). An MTV cutoff value of greater than 10.2cm(3) was found to significantly affect survival.
  
  
  
  Due to the reproducibility of MTV findings, this study validates MTV as an independent prognostic factor for OCSCC treated with primary surgery.
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Han
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Hadi
authors.initials: H
authors.lastname: Seikaly
authors.affiliation: Division of Radiation Oncology, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Nhu-Tram
authors.initials: NT
authors.lastname: Nguyen
authors.affiliation: Department of Radiology, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Jonathan T
authors.initials: JT
authors.lastname: Abele
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Florida, Gainesville, FL, USA.
authors.forename: Peter T
authors.initials: PT
authors.lastname: Dziegielewski
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Harris
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, Edmonton, Alberta, Canada. Electronic address: dan.o'connell@albertahealthservices.ca.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: O'Connell
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000601:surgery*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000175:diagnosis* / Q000601:surgery*; D009364:Neoplasm Recurrence, Local; D049268:Positron-Emission Tomography; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: Imaging; Metabolic tumor volume; Oral cavity squamous cell carcinoma; Pet-ct; Prognostic marker