Presence of 10 transformation zone cells in endocervical curettage should not be required for adequacy

In another publication, we concluded endocervical curettage (ECC) should have a minimum number of squamous cells for adequacy, similar to the requirements for adequate cervical Papanicolaou smears. Here, we investigate if also, similar to cervical Papanicolaou smears, the presence of at least 10 cells from the endocervical/transformation zone (EC/TZ) in ECCs should be used as a quality assurance measure or if, instead, at least 10 EC/TZ cells should be part of the adequacy criteria for ECC, with an emphasis on diagnosis of at least high-grade squamous dysplasia (HGD).

All patients with at least HGD diagnosed on an excisional biopsy specimen (loop electrosurgical excision procedure [LEEP]) from May 1, 2018, to December 31, 2019, and an ECC in the preceding 6 months at our institution were included. Number of EC/TZ cells present in ECCs was counted visually and categorized as less than or greater than 10 TZ cells. A χ2 test was used to evaluate the proportion of ECCs with and without HGD and the presence or absence of at least 10 EC/TZ cells. Given our recent work encouraging at least 1000 squamous cells in an ECC to be considered adequate, we also evaluated only ECCs with greater than 1000 squamous cells with and without HGD and the presence or absence of at least 10 EC/TZ cells. P value was <.05.

Fifty-one LEEPs with HGD and a preceding ECC in the previous 6 months were identified. Of the 51 ECCs, 6 had fewer than 10 EC/TZ cells and 45 had at least 10 EC/TZ cells. A similar proportion of the ECCs with HGD had at least 10 EC/TZ cells as those without HGD (93% vs 86%, P = .53). Using only ECCs with greater than 1000 squamous cells, we still found no statistical difference in the proportion of ECCs with HGD having greater than 10 EC/TZ cells compared to those without HGD (91% vs 100%, P = .49).

We found that the presence of at least 10 EC/TZ cells does not increase the likelihood of finding HGD in an ECC performed in the 6 months prior to a LEEP with HGD. Similar to the use of the TZ component in cervical Papanicolaou smears, the presence or absence of at least 10 TZ cells in an ECC should only be considered a quality assurance measure and not be used as a criterion for adequacy of the specimen.