title: Submandibular gland-sparing intensity modulated radiotherapy in the treatment of head and neck cancer: sites of locoregional relapse and survival.
abstract: OBJECTIVE
  To evaluate the patterns of locoregional relapse and survival following submandibular gland (SMG)-sparing intensity modulated radiotherapy (IMRT).
  
  
  METHODS
  Eighty patients with laryngeal (n = 15), oropharyngeal (n = 50), hypopharyngeal (n = 11) or nasopharyngeal cancer (n = 4) were treated by submandibular gland-sparing IMRT for head and neck squamous cell cancer between July 2000 and December 2008. All patients were treated by bilateral IMRT. Thirty-nine (49%) received definitive radiotherapy (RT) and 41 (51%) postoperative RT. The contralateral parotid gland (PG) and SMG were included in the dose optimization planning program with intent to keep the mean doses for PG and SMG below 23 Gy and 28-30 Gy, respectively. The ipsilateral glands were also spared when considered feasible.
  
  
  RESULTS
  During a median follow-up time of 51 months (range, 24-117 months) nine local recurrent tumors were observed. Four of these nine patients were salvaged by surgery with no further recurrence. All local recurrences were located within the high-dose CTVs. None of the locally recurrent cancers were located at the vicinity of the spared PGs or SMGs. No recurrent tumors were observed in the contralateral neck. The Kaplan-Meier estimate for local control at five years following IMRT was 88% for the whole cohort and the corresponding figure for local control following salvage surgery was 94%. The estimates for five-year overall survival and disease-specific survival were 85% and 90%, respectively.
  
  
  CONCLUSIONS
  In selected head and neck cancer patients who are estimated to have a low risk of cancer recurrence at the nodal levels I-II and who are treated with SMG-sparing IMRT the risk of cancer recurrence at the vicinity of the spared salivary glands is low.
authors.affiliation: Department of Oncology, Helsinki University Central Hospital, Finland.
authors.forename: Juhani
authors.initials: J
authors.lastname: Collan
authors.forename: Mika
authors.initials: M
authors.lastname: Kapanen
authors.forename: Antti
authors.initials: A
authors.lastname: Mäkitie
authors.forename: Heidi
authors.initials: H
authors.lastname: Nyman
authors.forename: Heikki
authors.initials: H
authors.lastname: Joensuu
authors.forename: Mikko
authors.initials: M
authors.lastname: Tenhunen
authors.forename: Kauko
authors.initials: K
authors.lastname: Saarilahti
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000532:radiotherapy; D015331:Cohort Studies; D005260:Female; D006258:Head and Neck Neoplasms / Q000401:mortality* / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000401:mortality*; D009367:Neoplasm Staging; D059351:Organ Sparing Treatments; D011832:Radiation Injuries / Q000517:prevention & control*; D050397:Radiotherapy, Intensity-Modulated; D013363:Submandibular Gland / Q000528:radiation effects*; D015996:Survival Rate; D016896:Treatment Outcome