Comparative risk of high-grade histopathology diagnosis after a CIN 1 finding in endocervical curettage versus cervical biopsy

OBJECTIVE: No evidence-based clinical management recommendations exist for women with an endocervical curettage (ECC) cervical intraepithelial neoplasia grade 1 (CIN 1) result when the concurrent cervical biopsy is not high-grade. For women with these pathologic findings, we assessed their short-term risk of high-grade histopathologic diagnosis in the Calgary Health Region where ECC was routinely performed. MATERIALS AND METHODS: We analyzed pathology and colposcopy reports from 1,902 referral colposcopies where both ECC and biopsies were normal or CIN 1. We calculated the short-term risk of CIN 2 or more severe (CIN 2+) detected 12 to 24 months after colposcopy. Pearson χ tests or Fisher exact tests were used to compare risks of a CIN 2+ diagnosis between combinations of test results and strata of risk factors. RESULTS: The short-term risk of CIN 2+ was the same after a CIN 1 biopsy and CIN 1 ECC (4.9% of 1,389 vs 5.0% of 359, respectively, p = .37). Compared with low-grade referral cytology, the risk of CIN 2+ after high-grade cytology was elevated significantly for CIN 1 ECC (13.3% vs 3.3%, p < .01) and nonsignificantly for CIN 1 biopsy (7.1% vs 4.6%, p = .12). CONCLUSIONS: After low-grade cytology, the short-term risk of a high-grade histologic diagnosis in women with either CIN 1 ECC or biopsy is equivalent, suggesting similar management. A CIN 1 ECC may warrant different management in the context of high-grade referral cytology.