Ability of visual tests to predict underlying cervical neoplasia. Colposcopy and speculoscopy

To describe the attributes of colposcopy and a low-power, magnified examination that utilizes chemiluminescent illumination (speculoscopy) in the visualization of cervical epithelium in a predefined, high-risk population and to compare how the two tests predict cervical histology.

During this multicenter, prospective study, 395 women who were referred to our colposcopy clinic underwent a repeat cervical smear and speculoscopy followed immediately by colposcopy. Abnormal colposcopic lesions were biopsied and endocervical curettage performed when indicated. Histologic diagnoses were compared with cytology, speculoscopy and colposcopy results.

Colposcopy was more sensitive than speculoscopy in the detection of cervical neoplasia (97% vs. 82%) (P < .001) and was superior in visualizing focal lesions and vascular patterns. An antecedent acetowhite abnormality detected during speculoscopy was highly predictive of subsequent abnormal colposcopy (97% positive predictive value). The "overall" rate of acetowhite lesions during speculoscopy was nearly half the rate during colposcopy (P < .001).

Colposcopy is better suited than speculoscopy to the follow-up of patients with abnormal cervical cytology because it facilitates lesion grading and assists in directing biopsies. Speculoscopy is best utilized as a dichotomous screening test based on the presence or absence of at least one well-demarcated acetowhite lesion and may be more suitable than colposcopy as an adjunct to cervical cancer screening due to its lower overcall rate. The biophysical properties of blue-white chemiluminescent light as it relates to the diagnosis of cervical neoplasia are discussed.