Cervical biopsy strategy during colposcopy: evidence from a retrospective study

To study the factors affecting the detection of cervical precancerous lesions and cervical carcinoma during colposcopy and to provide evidence for optimizing colposcopy biopsy strategies. This is a single-center retrospective study which included 1007 female patients who underwent colposcopy and cervical biopsy between June 2022 and November 2023. The pathological results of the biopsies served as the reference standard. Factors related to the detection rate of cervical precancerous lesions and cervical carcinoma were analysed. Subgroup analyses were performed according to the different cervical transformation zones to compare the efficiency of different biopsy methods. Abnormal cytology and high-risk human papillomavirus (HPV) infection had high predictive values for cervical precancerous lesions and cervical carcinoma. The accuracy of colposcopy was affected by the type of cervical transformation zone. Various biopsy methods offered distinct advantages depending on the type of transformation zone involved. For the type I transformation zone, the detection rates of high-grade lesions were higher in the four-quadrant directed biopsy group (31.4% vs. 21.2%, P = 0.038) and the multipoint biopsy group (28.4% vs. 12.5%, P = 0.001) than in the corresponding control groups. For the type II transformation zone, the detection rate of high-grade lesions was greater when multipoint biopsy was performed at ≥ 3 sites (21.7% vs. 12.2%, P = 0.021). For the type III transformation zone, neither four-quadrant directed biopsy, multipoint biopsy, nor endocervical curettage (ECC) significantly improved the detection rate of high-grade lesions. This study provides a basis for determining biopsy strategy during colposcopy. Biopsy is recommended for patients with both high-risk HPV infection and abnormal cytology. Four-quadrant directed biopsy or multipoint biopsy is suggested for type I transformation zones, whereas multipoint targeted biopsy is suggested for type II transformation zones. The observation and management of type III transformation zones by colposcopy remain challenging.