Repeat cervical cytology at the time of colposcopy. Is there an added benefit?

OBJECTIVE To determine if repeating the Pap smear (PS) at colposcopy offers added benefit in the detection of cervical squamous intraepithelial lesions (SILs). STUDY DESIGN Eight hundred fifty-two women were subjects of this study. Patients with cervical SIL were defined as women with SIL on the repeat PS, or SIL on the colposcopic cervical biopsy (bx) or a negative repeat PS and bx but confirmed SIL on both the previous and follow-up PS or bx. The sensitivities of repeat PS and bx in detecting SIL were calculated. The chi 2 test was used to assess statistical significance. The total cost of repeating the PS was calculated by multiplying the total number of patients (852) by the estimated cost of a single PS ($25). RESULTS The sensitivities of repeat PS, bx and PS/bx combined were .89, .69 and .92 for low grade SIL (LSIL) and .74, .77 and .98 for high grade SIL (HSIL), respectively (P < .0001). Sixteen percent of the HSIL and 28% of the LSIL cases were diagnosed on repeat PS only (negative bx). If repeat PS was omitted, $21,300 would have been saved.