title: Determinants of treatment waiting times for head and neck cancer in the Netherlands and their relation to survival.
abstract: BACKGROUND
  Waiting to start treatment has been shown to be associated with tumor progression and upstaging in head and neck squamous cell carcinomas (HNSCCs). This diminishes the chance of cure and might lead to unnecessary mortality. We investigated the association between waiting times and survival in the Netherlands and assessed which factors were associated to longer waiting times.
  
  
  METHODS
  Patient (age, sex, socioeconomic status (SES), tumor (site, stage) and treatment (type, of institute of diagnosis/treatment) characteristics for patients with HNSCC who underwent treatment were extracted from the Netherlands Cancer Registry (NCR) for 2005-2011. Waiting time was defined as the number of days between histopathological diagnosis and start of treatment. Univariable and multivariable Cox regression was used to evaluate survival.
  
  
  RESULTS
  In total, 13,140 patients were included, who had a median waiting time of 37days. Patients who were more likely to wait longer were men, patients with a low SES, oropharynx tumors, stage IV tumors, patients to be treated with radiotherapy or chemoradiation, and patients referred for treatment to a Head and Neck Oncology Center (HNOC) from another hospital. The 5-year overall survival was 58% for all patients. Our multivariable Cox regression model showed that longer waiting time, was significantly related to a higher hazard of dying (p<0.0001).
  
  
  CONCLUSIONS
  This is the first large population-based study showing that longer waiting time for surgery, radiotherapy or chemoradiation is a significant negative prognostic factor for HNSCC patients.
authors.affiliation: Department of Head and Neck Surgery and Oncology, Netherlands Cancer Institute, Amsterdam, The Netherlands. Electronic address: m.v.harten@nki.nl.
authors.forename: Michel C
authors.initials: MC
authors.lastname: van Harten
authors.affiliation: Department of Radiation Oncology (MAASTRO), Research Institute GROW, Maastricht University, Maastricht, The Netherlands.
authors.forename: Frank J P
authors.initials: FJ
authors.lastname: Hoebers
authors.affiliation: Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Kross
authors.affiliation: Department of Biometrics, Netherlands Cancer Institute, Amsterdam, The Netherlands.
authors.forename: Erik D
authors.initials: ED
authors.lastname: van Werkhoven
authors.affiliation: Department of Head and Neck Surgery and Oncology, Netherlands Cancer Institute, Amsterdam, The Netherlands; Department of Oral and Maxillofacial Surgery, Academic Medical Center, University of Amsterdam, The Netherlands; Department of Phonetic Sciences, University of Amsterdam, The Netherlands.
authors.forename: Michiel W M
authors.initials: MW
authors.lastname: van den Brekel
authors.affiliation: Department of Research, Comprehensive Cancer Centre The Netherlands (IKNL), Utrecht, The Netherlands; Department of Epidemiology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.
authors.forename: Boukje A C
authors.initials: BA
authors.lastname: van Dijk
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001071:Appointments and Schedules; D002294:Carcinoma, Squamous Cell / Q000628:therapy*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006258:Head and Neck Neoplasms / Q000628:therapy*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011379:Prognosis; D016016:Proportional Hazards Models; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult
keywords: HNSCC; Head and neck cancer; Head and neck squamous cell carcinoma; Prognosis; Survival; Treatment delay; Waiting time