title: A clinical decision analysis of cryotherapy compared with expectant management for cervical dysplasia.
abstract: BACKGROUND
  Screening for precursors of cervical cancer with colposcopic examination for women with abnormal Papanicolaou (Pap) smears identifies those with cervical dysplasia. Though the majority of mild dysplasias (CIN I) will regress, many are treated with cryotherapy.
  
  
  METHODS
  We used decision analysis to compare immediate cryotherapy with expectant management (following with another Pap smear or colposcopy, with treatment reserved for progression or a duration of 2 years). The decision tree included the possibility of more invasive surgical procedures if the cryotherapy was ineffective or if the dysplasia progressed in extent of cervical involvement or in grade. Probabilities were derived from literature review and expert judgment. The analysis considered the disutility of the follow-up examinations, cryotherapy, and the more invasive procedures, using expert assessment.
  
  
  RESULTS
  Using the baseline assumptions, expectant management led to a better outcome for most patients (57%), who recover with no procedure. However, more patients treated with expectant management required surgical procedures (loop electrosurgical excisional procedure, conization, or, rarely, hysterectomy) than did those treated with immediate cryotherapy. In the expected disutility analysis, expectant management was better than immediate cryotherapy. Sensitivity analysis showed that three factors had the potential to change the recommendation of the analysis: (1) the probability the dysplasia will regress, (2) the disutility of the process of expectant management, and (3) the disutility of invasive procedures compared with cryotherapy.
  
  
  CONCLUSIONS
  The analysis indicated that expectant management is preferable to immediate cryotherapy for women with histologically proven mild cervical dysplasia. However, this conclusion depended on assumptions about three factors for which there is insufficient evidence in the literature. More research is needed.
authors.affiliation: Department of Family and Preventive Medicine, University of Oklahoma Health Sciences Center, Oklahoma City 73104, USA. robert-hamm@ouhsc.edu
authors.forename: R M
authors.initials: RM
authors.lastname: Hamm
authors.forename: V
authors.initials: V
authors.lastname: Loemker
authors.forename: K L
authors.initials: KL
authors.lastname: Reilly
authors.forename: G
authors.initials: G
authors.lastname: Johnson
authors.forename: P
authors.initials: P
authors.lastname: Dubois
authors.forename: K
authors.initials: K
authors.lastname: Staveley-O'Carroll
authors.forename: J
authors.initials: J
authors.lastname: Brand
authors.forename: T
authors.initials: T
authors.lastname: Owens
authors.forename: K
authors.initials: K
authors.lastname: Smith
mesh_terms: D003127:Colposcopy; D017679:Cryotherapy; D003661:Decision Support Techniques; D003663:Decision Trees; D005260:Female; D006801:Humans; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis / Q000628:therapy*; D002578:Uterine Cervical Dysplasia / Q000175:diagnosis / Q000628:therapy*