Table 2 Cell morphological features of different cervical lesions after methylene blue staining under microendoscopy

cervicitis

No abnormal features were found. Regularly arranged round-like cervical epithelial cells with light blue cytoplasm and dark blue nuclei that appear as uniform, small round.

LSIL

A few enlarged or irregular nuclei were present against a background of uniformly distributed round nuclei.

HSIL

Most cells had enlarged nuclei, increased nuclear-cytoplasmic ratio, darkly stained nuclei, and irregular nuclear contours, with relatively regular arrangement. Cervical canal columnar epithelial cells were distributed in feathery or papillary aggregates. Morphologically abnormal epithelial cells were often accompanied by pathological blood vessels. There were lymphocytes infiltration around the lesion.

AIS

Crowded glandular epithelial cells with lightly stained lacy-like cytoplasm and darkly stained enlarged nuclei. Disordered cervical canal columnar epithelial cells with crowded, enlarged heteromorphic nuclei, and the structure of the cervical glands was obscure. Morphologically abnormal epithelial cells were often accompanied by pathological blood vessels.

SCC

Disorganized cervical epithelial cells with numerous necrotic cell debris. Significantly enlarged nuclei, highly irregular nuclear contour with folds and dents, uneven intensity staining nuclei, and characteristic nuclear overlap. The normal structure of the cervical glands was lost, and cancer columnar epithelial cells were scattered irregularly with enlarged heteromorphic nuclei. Morphologically abnormal epithelial cells were often accompanied by pathological blood vessels. Possible lymph node structures surrounding the cancer cells.