title: Combination of p16 levels and pre-radiotherapy factors predicts outcome in patients treated for oropharyngeal carcinoma.
abstract: OBJECTIVE
  To explore whether tumor biomarkers and pre-treatment factors correlate with treatment outcome in patients with oropharyngeal squamous cell carcinoma (SCC).
  
  
  METHODS
  Fifty-seven consecutive patients diagnosed with oropharyngeal SCC were treated using intensity modulated radiotherapy (IMRT). Thirty-four (60%) patients were treated with definitive chemoradiotherapy to a median total dose of 70 Gy and 23 (40%) were treated with postoperative RT to a median total dose of 66 Gy. Concurrent platinum- based chemotherapy was used in 51 patients (90%) and cetuximab in 3 (5%) patients.
  
  
  RESULTS
  Forty-four (77%) cases were positive and 13 (23%) were negative for p16 expression. Eighty-eight percent of non-smokers, 87% of smokers in their remote past and 56% of active smokers were diagnosed with p16-positive cancer. After 22 months median follow up, 51 (89%) patients were alive. Forty-five (77%) patients were without evidence of disease at their last follow up, 82% of the patients with p16-positive tumors vs 58% of those with p16-negative cancer, respectively (p= 0.04). Locoregional disease-free survival was 82% for the entire cohort, 91% for patients treated postoperatively and 76% for patients treated with definitive chemoradiotherapy. Five (9%) patients developed distant metastases, and 3 (5%) developed new malignancies. One third of the patients with pre-RT hemoglobin level of ≤ 11 g/dL experienced persistent/recurrent disease; 80% of patients with hemoglobin ≤ 11 g/dL were smokers and 42% had p16-negative tumors.
  
  
  CONCLUSIONS
  Smoking, p16 expression and pre-RT anemia are interrelated and influence outcome in oropharyngeal cancer patients and should be evaluated as stratifying variables in further clinical trials.
authors.affiliation: Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, USA.
authors.forename: V
authors.initials: V
authors.lastname: Bar-Ad
authors.forename: Z X
authors.initials: ZX
authors.lastname: Wang
authors.forename: B
authors.initials: B
authors.lastname: Leiby
authors.forename: M
authors.initials: M
authors.lastname: Tuluc
mesh_terms: D000328:Adult; D000368:Aged; D000740:Anemia / Q000150:complications; D014408:Biomarkers, Tumor / Q000032:analysis*; D002294:Carcinoma, Squamous Cell / Q000737:chemistry* / Q000209:etiology / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary; D059248:Chemoradiotherapy / Q000009:adverse effects / Q000401:mortality; D016009:Chi-Square Distribution; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis*; D018572:Disease-Free Survival; D005260:Female; D006258:Head and Neck Neoplasms / Q000737:chemistry* / Q000209:etiology / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009959:Oropharyngeal Neoplasms / Q000737:chemistry* / Q000209:etiology / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000401:mortality; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D000077195:Squamous Cell Carcinoma of Head and Neck; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D019941:Cyclin-Dependent Kinase Inhibitor p16