ABSTRACT
OBJECTIVE: We studied the anatomic changes that occur in the ectocervix after cryotherapy and the role these changes play in the adequacy of follow-up colposcopic examination.
STUDY DESIGN: We retrospectively reviewed patients’ charts.
POPULATION: Between January 1, 1991, and December 1, 1995, 268 women underwent 2 colposcopic examinations in 7 state-run public health clinics.
OUTCOMES MEASURED: The likelihood that a follow-up colposcopic examination would be inadequate.
RESULTS: Of the 268 women who underwent 2 colposcopic examinations during the study period, 83 had cryotherapy, 24 had loop excision of the ectocervical portion or cervical conization, and 96 had no procedure. Sixty-five were excluded because of missing data. Subjects were similar with respect to age, whether endocervical curettage was performed, presence of cervical dysplasia or human papilloma virus, and whether glandular involvement was noted. Patients who had cryotherapy had an increased likelihood of inadequate follow-up colposcopic examination compared with women who had no procedure (adjusted odds ratio = 18.7, 95% confidence interval = 7.0–49.8).
CONCLUSIONS: Undergoing cryotherapy of the uterine cervix increases the risk that a follow-up colposcopic examination will be inadequate. Given the reported high rates of regression of mild and moderate cervical dysplasia and the risks posed by possibly unnecessary procedures performed after inadequate colposcopic examination, a trend toward less aggressive therapy and watchful waiting may be appropriate but should be investigated in a controlled clinical trial.
KEY POINTS FOR CLINICIANS
- Based on this study, cervical cryotherapy increases the risk that a follow-up colposcopic examination will be inadequate.
- Further studies are needed to determine the most effective treatment for mild cervical dysplasia and possible local effects of cryotherapy.
Cryotherapy is an accepted procedure for treating low-grade cervical dysplasia.1,2 Only minor modifications of the precise technique of cryotherapy application have occurred since its inception. Currently the double-freeze technique of cryotherapy is an accepted treatment for mild and focal moderate dysplasia of the uterine cervix.3 Cervical cryotherapy is used widely not only because of its proven efficacy but also because of its ease of use in the outpatient setting and lack of known significant side effects. The procedure can be performed in the office setting without the use of local or general anesthesia, making it superior to the more invasive procedures performed before the availability of cryotherapy (eg, cervical conization and hysterectomy).
There has been limited investigation of the effects of cryotherapy on the anatomy of the uterine cervix. Whereas one study showed that cryotherapy has no effect on subsequent fertility or pregnancy outcome,4 another in adolescents reported cervical stenosis and pelvic inflammatory disease as possible treatment side effects.5 In addition, a study published in 1984 by Jobson and Homesley reported higher rates of retraction of the proximal squamocolumnar junction into the endocervical canal in patients undergoing cryotherapy compared with patients undergoing carbon dioxide laser ablation6; 47% of the follow-up colposcopic examinations were inadequate in that study population. Adequacy of colposcopic examination is defined as complete visualization of the transformation zone, visualization of the entire lesion, if present, and correlation between cytologic and histologic findings and the colposcopist’s impression.7 Failure to meet any one of these criteria leads to an inadequate colposcopic examination requiring further, more invasive evaluation. This study compared the rate of adequate and inadequate colposcopic examinations in women with and without a history of cryotherapy. Other factors found to influence the adequacy of follow-up colposcopy also are described.
Methods
We performed a retrospective cohort study using data collected from 7 of 14 state-run public health clinics. These 7 sites included rural and urban clinics. All women undergoing at least 2 colposcopic examinations in these clinics between January 1, 1991, and December 1, 1995, were included. Women underwent initial colposcopic examination after an abnormality was noted on a screening Pap test. Only women who had both colposcopic examinations in the same clinic were included. Care provided in these clinics included Pap test screening, colposcopic examinations, and treatment of identified cervical dysplasia with cervical cryotherapy, conization, and loop excision of the ectocervical portion (LEEP). State-contracted physicians trained in obstetrics and gynecology followed women who attended these clinics.
Chart review was used to determine the adequacy of the initial examination, whether an intervening procedure was done, and the adequacy of follow-up colposcopic examination. Adequacy was documented by the physician performing the colposcopic examination with the use of a standard form consistent among clinics. The accepted criteria for adequacy were used, and each colposcopic examination was documented as adequate or inadequate based on the colposcopist’s findings. Charts were reviewed and data were abstracted by 3 reviewers. Cervical biopsy results, presence of human papilloma virus (HPV) noted on routine cytology, endocervical curettage (ECC) results, and routine demographic data also were recorded. The management and therapeutic protocols were consistent across the 7 clinics.