What is TCT and Pap Smear? TCT stands for thinprep cytologic test and represents one of the most advanced screening methods available. Of course, due to the rapid development of medicine, new cytologic testing methods have been introduced, and after TCT, the U.S. FDA approved LCT for clinical use in 1999; the so-called LCT is the autocyteprep cytologic test, also known as liquid-based cytologic test (LCT). LCT, also known as liquid-based cytologic test (LCT), is different from TCT in that it can automatically test 48 specimens. In the cell reading progress, when the introduction of CCT, the so-called CCT is computer-assisted cytologic test (computer-assisted cytologic test, ) the English abbreviation, also known as cell computerized scanning, CCT system memorizes a large number of normal and abnormal cells, every hundred smears for a group of cervical smears for automatic scanning. After the computerized rule system imager, the suspected abnormal cells are processed in color and stored digitally on digital tape for examination. Then, the selected image data is re-examined, and the pathologist first reviews the digitized images recorded on disk on each smear, focusing on the screened abnormal cell images, thus achieving the best combination of computer and human brain intelligence. Due to the expensive nature of CCT testing equipment, it is currently used mostly for quality control of screening specimens. What is Pap Smear? Papanicolaou GN (Papanicolaou for short) first published the diagnosis of cervical cancer with vaginal exfoliated cells in 1941, and two years later Papanicolaou co-authored a book with Trout, “Diagnosis of Cervical Cancer Tumors by Vaginal Smear,” which led to the rapid development of cytological diagnostic techniques in gynecology. In the beginning, Bachmann chose vaginal exfoliated cells, which proved to be too high a false negative in later studies and was gradually replaced by cervical exfoliated cells.