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Updated: May 14, 2026

Establishment and Evaluation of a Risk Prediction Model for Pathological Escalation of Gastric Low-Grade Intraepithelial Neoplasia
Published on: February 16, 2024
Comparative risk of high-grade histopathology diagnosis after a CIN 1 finding in endocervical curettage versus
Julia C Gage1, Máire A Duggan, Jill G Nation
1Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20892-7234, USA. gagej@mail.nih.gov
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.
