Combining endometrium sampling device and SurePath preparation to screen for endometrial carcinoma: a validation study

Abstract

Background: The aim of this study was to compare specimen adequacy of SAP-1 provided for cytology with that of dilation and curettage (D & C) or hysteroscopy for histology, and evaluate the accuracy of combining endometrium sampling by SAP-1 and liquid-based cytology using SurePath preparation for screening endometrial carcinoma and its precursor.

Methods: Endometrial specimens from women (n = 1514) with risk factors were obtained using an SAP-1 device for cytological analysis; histological samples were obtained from 375 of these women who underwent D & C or hysteroscopy. Cytological specimens were prepared to liquid-based smear using SurePath technology and stained by Papanicolaou. Histological samples were processed in routine pathology and stained by hematoxylin and eosin.

Results: Adequate specimens for cytology were obtained from 1458/1541 patients (96.3%), while adequate samples for pathology were obtained from 285/375 patients (76%). However, for postmenopausal women, 1006 of 1045 cytology (86.3%) were adequate, 153 of 238 histology (64.3%) were adequate, it was easier to collect cytological specimens than histological specimens (P < 0.05). The accuracy of endometrial cytology for detecting endometrial carcinoma and its precursor was 92.4% (sensitivity, 73%; specificity, 95.8%; positive predictive value, 75%; and negative predictive value, 95.3%).

Conclusions: Endometrial cytology using SAP-1 sampling and SurePath preparation may be a reliable approach for screening patients with endometrial carcinoma and its precursor.

Figure 1

The SAP-1 sampling device.

Figure 2

Steps for obtaining samples using the SAP-1 device

Figure 3

(a) Negative for endometrial lesions: Long, straight tube-shaped cell clumps with a small amount of stromal cells on the margin is the most common type of cell clumps in the proliferative endometrium, observed using a low-power microscope (Papanicolaou stain, ×20); (b) Benign endometrium: Dilated and branched cell clumps are always seen. The contour of the cell clumps is smooth and occasionally a few stromal cells can be observed (Papanicolaou stain, ×40); (c) Atypical endometrial cell: Double-layer or folded irregular cell clumps are observed (Papanicolaou stain, ×20); (d) Suspected endometrial carcinoma: Papillo-shaped bordered cell clumps with atypical cells can be observed (Papanicolaou stain, ×100).

Figure 4

(a) Negative for endometrial lesion: Regularly arranged and mono-layer endometrial cells with an oval or round nucleus. The spaces between nuclei are regular, and the chromatin in endometrial cells is delicate (Papanicolaou stain, ×100); (b) Benign endometrium: Crowded cells arranged into a single layer with delicate chromatin and a small nucleolus (Papanicolaou stain, ×100); (c) Atypical endometrial cell: The spaces in atypical cells are heterogeneous. Some areas are sparse, while others are crowded or even overlapping. The chromatin is coarse (Papanicolaou stain, ×100); (d) Suspected carcinoma: Variable size cells with obviously round nucleoli. The nucleus to cytoplasm ratio is increasing. Varying and large vacuoles appear inside the cytoplasm (Papanicolaou stain, ×100).