Intensity-modulated radiotherapy outcomes for oropharyngeal squamous cell carcinoma patients stratified by p16 status.

Academic Article

Abstract

  • BACKGROUND: Patients with oropharyngeal squamous cell carcinoma (OPSCC) treated with intensity-modulated radiotherapy (IMRT) were stratified by p16 status, neck dissection, and chemotherapy to correlate these factors with outcomes. METHODS: A total of 112 patients with OPSCC treated with IMRT from 2002 to 2008 were retrospectively analyzed. All patients received RT to 66-70 Gray. Forty-five of the tumors were p16 positive (p16+), 27 were p16 negative (p16-), and 41 had unknown p16 status. Sixty-two patients had postradiation neck dissections. Nine patients with p16- tumors and 28 patients with p16+ tumors received chemotherapy. The distribution of T, N, and stage grouping among the p16+ and p16- patients was not significantly different, and 87.5% patients had stage III/IV disease. RESULTS: The median follow-up was 26.3 months. For patients with p16+ tumors, p16- tumors, and the overall cohort, the actuarial 3-year locoregional progression-free survival rate was 97.8%,73.5%, and 90.5% respectively (P = .006) and the disease-free survival rate was 88.2%, 61.4%, and 81.7%, respectively (P = .004). Patients with p16+ tumors had an 89.5% and 87.5% pathologic complete response (CR) on neck dissection with and without chemotherapy, respectively. In contrast, patients with p16- tumors had a 66.7% and 25.0% pathologic CR on neck dissection with and without chemotherapy, respectively. CONCLUSIONS: In this series, p16 status was found to be a significant predictive biomarker and patients with p16+ tumors had much better outcomes than patients with p16- tumors. Further investigation is warranted to determine whether less intense therapy is appropriate for selected patients with p16+ OPSCC, whereas more aggressive strategies are needed to improve outcomes in patients with p16- disease.
  • Published In

  • Cancer  Journal
  • Keywords

  • Carcinoma, Squamous Cell, Combined Modality Therapy, Cyclin-Dependent Kinase Inhibitor p16, Female, Genes, p16, Humans, Male, Middle Aged, Neck Dissection, Neoplasm Proteins, Oropharyngeal Neoplasms, Radiotherapy Dosage, Radiotherapy, Intensity-Modulated, Treatment Outcome
  • Digital Object Identifier (doi)

    Author List

  • Shoushtari A; Meeneghan M; Sheng K; Moskaluk CA; Thomas CY; Reibel JF; Levine PA; Jameson MJ; Keene K; Read PW
  • Start Page

  • 2645
  • End Page

  • 2654
  • Volume

  • 116
  • Issue

  • 11