Objective: To examine the efficacy of the different modalities used to evaluate an initial abnormal Papanicolaou smear.
Methods: The study population comprised 214 nonpregnant women referred with a Papanicolaou smear diagnosis of cervical intraepithelial neoplasia. Each patient was evaluated by a repeat Papanicolaou smear, colposcopy, and colposcopically directed cervical biopsies. Immediate loop excision was performed to remove the entire transformation zone in all patients. Kappa statistics were calculated to determine agreement among the modalities, and logistic regression was used for determining relative risks (RR).
Results: There was 53% agreement between the initial and repeat Papanicolaou smears. When low-grade squamous intraepithelial lesion (SIL) was diagnosed by Papanicolaou smear, there was 89% agreement with the colposcopic impression. However, a colposcopic impression of high-grade SIL was found in only one-third of the women diagnosed with high-grade SIL by Papanicolaou smear. A comparison of the histology of the cervical biopsy and the loop specimen revealed 57% agreement. Univariate analysis indicated that each modality was able to predict the RR of high-grade dysplasia in the loop specimen at a statistical significance level of .05. A colposcopic impression of high-grade dysplasia conferred an RR of 7.43 (95% confidence interval [CI] 2.17-25.49) for high-grade dysplasia in the loop specimen. An initial Papanicolaou smear diagnosis of high-grade SIL did not contribute to the multivariate model for calculating the risk of high-grade dysplasia, as the RR was 1.6 (95% CI 0.68-3.81).
Conclusion: Patients with an initial Papanicolaou smear showing low-grade SIL would benefit from a repeat Papanicolaou smear and colposcopically directed biopsies before proceeding with loop diathermy. In contrast, patients with a colposcopic impression of high-grade dysplasia combined with high-grade SIL on Papanicolaou smear appear to be candidates for immediate loop excision.
(C) 1994 The American College of Obstetricians and Gynecologists