title: Primary tumor volume is an independent predictor of outcome within pT4a-staged tongue carcinoma.
abstract: BACKGROUND
  We evaluated the heterogeneity of primary tumor volume (PTV) within tumors of the same pT4a-staged tongue carcinoma and to elucidate the effects of PTV on treatment outcomes in patients with pT4a-staged tongue carcinoma.
  
  
  METHODS
  Fifty-eight patients with newly diagnosed pT4a-staged tongue carcinoma who received surgery were enrolled onto this study. Magnetic resonance imaging-derived PTV was measured by the summation-of-area technique.
  
  
  RESULTS
  The mean PTV was 24.55 ml, with a range of 5.32 to 119.64 ml. The receiver operating characteristic curve was applied, and the optimal cutoff volume was 23 ml. Large PTV was associated with a significantly poor disease-specific survival (P = 0.010) by the log rank test. The Cox regression model also revealed that large PTV (P = 0.026) and positive lymphatic node metastasis (P = 0.004) were statistically significant in the prognosis of T4a-staged tongue carcinoma.
  
  
  CONCLUSIONS
  A substantial variation of PTV was present within the same pT4a-staged tongue carcinoma, and PTV represented an important prognostic factor. In the light of these findings, we suggest that taking the PTV into account in pT4a-staged tongue carcinoma would better refine the newest revised T classification, and the treatment strategies may be different.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Changhua Christian Hospital, Changhua, Taiwan. 53780@cch.org.tw
authors.forename: Mu-Kuan
authors.initials: MK
authors.lastname: Chen
authors.forename: Chih-Ming
authors.initials: CM
authors.lastname: Chen
authors.forename: Ming-Che
authors.initials: MC
authors.lastname: Lee
authors.forename: Li-Sheng
authors.initials: LS
authors.lastname: Chen
authors.forename: Hui-Chuan
authors.initials: HC
authors.lastname: Chen
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000473:pathology* / Q000628:therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011300:Preoperative Care; D011379:Prognosis; D011446:Prospective Studies; D012189:Retrospective Studies; D014062:Tongue Neoplasms / Q000473:pathology* / Q000628:therapy; D047368:Tumor Burden