title: Persistent pain and sensory disturbances after treatment for breast cancer: six year nationwide follow-up study.
abstract: OBJECTIVE
  To examine the development of persistent pain after treatment for breast cancer and to examine risk factors associated with continuing pain.
  
  
  METHODS
  Repeated cross sectional study in a previously examined nationwide cohort. All eligible women who underwent surgery for primary breast cancer in Denmark in 2005 and 2006 and were examined in 2008 were surveyed again with the same questionnaire.
  
  
  METHODS
  Surgical centres in Denmark.
  
  
  METHODS
  Prevalence, location, and severity of persistent pain after treatment for breast cancer in well defined treatment groups and changes in pain reporting and sensory disturbances from 2008 to 2012.
  
  
  METHODS
  In 2012, 2828 women were eligible in our database, and 108 were excluded. Exclusion criteria were death; new, recurrent, or other cancer; reconstructive breast surgery; and emigration.
  
  
  RESULTS
  2411 (89%) women returned the questionnaire. Prevalence of persistent pain after treatment for breast cancer ranged from 22% to 53% depending on treatment. In 2012, 903 (37%) women reported such pain, a fall from 45% in 2008. Of these, 378 (16%) reported pain of ≥ 4 on a numerical rating scale (scale 0-10), a fall from 19%. Among women reporting pain in 2008, 36% no longer reported it in 2012. In contrast, 15% of the women who did not report pain in 2008 reported it in 2012. Risk factors for having pain were axillary lymph node dissection rather than sentinel lymph node biopsy (odds ratio 2.04, 95% confidence interval 1.60 to 2.61; P<0.001) and age ≤ 49 (1.78, 1.25 to 2.54; P<0.001). No particular method of treatment or age was associated with an increase in pain from 2008 to 2012.
  
  
  CONCLUSIONS
  Persistent pain after treatment for breast cancer remains an important problem five to seven years later. The problem is not static as it can either progress or regress with time.
  
  
  BACKGROUND
  Clinicaltrials.gov NCT No 01543711.
authors.affiliation: Section for Surgical Pathophysiology, 7621 Rigshospitalet, University of Copenhagen, Blegdamsvej 9, DK-2100 Copenhagen, Denmark. mathias.kvist.mejdahl@rh.regionh.dk
authors.forename: Mathias Kvist
authors.initials: MK
authors.lastname: Mejdahl
authors.forename: Kenneth Geving
authors.initials: KG
authors.lastname: Andersen
authors.forename: Rune
authors.initials: R
authors.lastname: Gärtner
authors.forename: Niels
authors.initials: N
authors.lastname: Kroman
authors.forename: Henrik
authors.initials: H
authors.lastname: Kehlet
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000601:surgery*; D059350:Chronic Pain / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision / Q000009:adverse effects; D008408:Mastectomy / Q000009:adverse effects; D008875:Middle Aged; D011183:Postoperative Complications; D012307:Risk Factors; D012678:Sensation Disorders / Q000209:etiology*; D011795:Surveys and Questionnaires