Screening for colorectal cancer: Study on the shedding cells of feces
Authors: Wang Xin , Qin Xiaoxia , Zhang Jian , Zhao Yankai , Gao Yingchao 
Published: April 2024

Objective:
The objective of this study was to explore the enrichment efficiency of an improved fecal exfoliated cell enrichment method and its application in colorectal cancer screening.

Material and Methods:
Samples were collected from a cohort of 100 colorectal cancer patients being treated at the First Hospital of Hebei Medical University from January 2021 to June 2022. Patient samples were equally divided between control and experimental groups corresponding to the enrichment method being applied to the fecal exfoliated cells. Samples consisted of natural stool and bowel cleansing enema solution samples. The control group received the traditional three-layer integrated screen method, and the experimental group used nano-Fe3O4 folic acid magnetic beads to enrich the fecal exfoliated cells. The morphology of the extracted cells was observed by light microscopy through hematoxylin and eosin staining, and the positive rate of fecal occult blood test (FOBT) and the detection rate of colorectal cancer was compared between the two groups.

Results:
The FOBT-positive rates of natural feces and intestinal cleansing liquid in the control group were 74.00% and 90.00%, respectively, and the FOBT-positive rates of natural feces and intestinal cleansing liquid in the experimental group were 76.00% and 92.00%, respectively. The positive FOBT rate was high, and the difference was statistically significant (P = 0.037 and P = 0.029). The sensitivities of natural fecal exfoliation cytology in the control and experimental groups were 82.00% and 92.00%, respectively. The sensitivity of the experimental group was higher than that of the control group, and the difference was not statistically significant (P = 0.137). The sensitivities of the exfoliated cytology examination of the intestinal cleansing liquid in the control and experimental groups were 88.00% and 98.00%, respectively. The sensitivity of the experimental group was significantly higher than that of the control group, and the difference was statistically significant (P = 0.050). Cell smear results show that the exfoliated cells collected by the three-layer integrated sieve method are unevenly distributed, with overlapping cells and a large number of impurities blurring the background, seriously affecting the observation of cell morphology. The cell structure is blurred, stained unevenly, and arranged in a disorderly manner. The exfoliated cells collected by the nanofolic acid magnetic bead enrichment method are relatively evenly distributed, with no overlapping of cells in patches. The background is clear, and the morphology of each cell can be clearly observed. The cell structure is relatively clear, stained evenly, and distributed evenly.

Conclusion:
In the cytological examination of fecal exfoliation of colorectal cancer, the nano-Fe3O4 folic acid magnetic bead enrichment method can enrich more target cells compared with the traditional three-layer integrated screen method, improve the detection rate of colorectal cancer, and ensure the exfoliation The cell smears are of higher quality, providing a better sample for clinical assessment of the exfoliated cells. Nano-Fe3O4 folic acid magnetic beads enrichment method can become a simple, efficient, and relatively safe screening method for colorectal cancer, positively affecting early screening developments and diagnosis of colorectal cancer.