title: Regional control is preserved after dose de-escalated radiotherapy to involved lymph nodes in HPV positive oropharyngeal cancer.
abstract: OBJECTIVE
  To analyze a cohort of patients with HPV positive, oropharyngeal squamous cell carcinoma (OPSCC) treated with lower radiation dose to clinically involved lymph nodes.
  
  
  METHODS
  We retrospectively identified patients with HPV positive, OPSCC treated with definitive chemoradiotherapy (70-74.4Gy) to the primary site and, since a post-radiation neck dissection was planned, 54Gy to the involved nodal areas. Neck dissection was ultimately omitted in all cases due to complete response. All patients were treated with a 3 field approach with sequential boost plans. Composite plans were generated retrospectively and primary tumor and lymph node GTVs were contoured and nodes were expanded by 5mm to form a CTV. Mean dose, dose to 95% (D95) and dose to 99% (D99) were determined.
  
  
  RESULTS
  Fifty patients treated from 2008 to 2010 with 113 involved nodes were identified. The median age was 57years, and 6%, 46%, and 48% were current, former, and never smokers. Ninety percent of patients received concurrent cisplatin based chemotherapy. Median D95 and D99 to involved nodes were 59.8Gy and 55.9Gy respectively. At a median follow up of 54.1months, two patients developed nodal failure and four developed metastatic disease. Five year loco-regional control, disease free survival and overall survival were 96%, 81% and 86% respectively.
  
  
  CONCLUSIONS
  In this exploratory analysis, regional lymph node control in HPV positive oropharyngeal cancer was not compromised by dose de-escalated radiotherapy to involved nodes in the setting of concurrent cisplatin based chemotherapy.
authors.affiliation: Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Neil M
authors.initials: NM
authors.lastname: Woody
authors.affiliation: Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Shlomo A
authors.initials: SA
authors.lastname: Koyfman
authors.affiliation: Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Xia
authors.affiliation: Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Naichang
authors.initials: N
authors.lastname: Yu
authors.affiliation: Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Qingyang
authors.initials: Q
authors.lastname: Shang
authors.affiliation: Department of Hematology and Medical Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Adelstein
authors.affiliation: Department of Otolaryngology, Head and Neck Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Scharpf
authors.affiliation: Department of Otolaryngology, Head and Neck Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Burkey
authors.affiliation: Department of Hematology and Medical Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Tobenna
authors.initials: T
authors.lastname: Nwizu
authors.affiliation: Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Jerold
authors.initials: J
authors.lastname: Saxton
authors.affiliation: Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Radiation Oncology, Cleveland Clinic Florida, Weston, FL, USA. Electronic address: greskoj1@ccf.org.
authors.forename: John F
authors.initials: JF
authors.lastname: Greskovich
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy*; D003131:Combined Modality Therapy / Q000379:methods; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control*; D009959:Oropharyngeal Neoplasms / Q000532:radiotherapy*; D030361:Papillomavirus Infections / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Concurrent chemotherapy; HPV positive oropharyngeal cancer; Head and neck cancer; Radiotherapy dose deintensification