Bethesda System, The


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Bethesda System, The

(be-thez'da),

TBS

A system for reporting cervical or vaginal cytologic diagnoses. Use of TBS replaces the numerical designations (Class 1 through 5) of the Papanicolaou smear with descriptive diagnoses of cellular changes. Cellular changes are identified as benign; reactive, such as those due to inflammation, atrophy, radiation, or use of an intrauterine device; or malignant. Hormonal evaluation of vaginal smears is provided. Low-grade squamous intraepithelial lesions include what was previously called grade 1 cervical intraepithelial neoplasia (CIN 1) and cellular changes due to human papilloma virus, that is, koilocytosis. High-grade squamous intraepithelial neoplasia includes what was once identified as CIN 2 and CIN 3.
See: cervical cancer; cervical intraepithelial neoplasia