Gynecologic Cytology 101

Diagnostic entities found on the Pap test. For additional information, please see
Bethesda System Web Atlas.


Normal Cytology

Negative for Intraepithelial Lesions or Malignancy (NILM)


Common Infectious Diseases

Herpes simplex virus


Abnormal (precancerous) Lesions

Atypical Squamous Cells of Undetermined Significance  (ASC-US)
Atypical Squamous Cells cannot rule out a High-grade Lesion (ASC-H)
Low-grade Squamous Intraepithelial Lesion (LSIL)
High-grade Squamous Intraepithelial Lesion (HSIL)


Cancerous Lesions

Squamous cell carcinoma
Adenocarcinoma, endocervical type
Adenocarcimona, endometrial type
Adenocarcinoma, ovarian type



DeMay RM. Art and Science of Cytopathology, 2nd ed. Chicago, IL: American Society of Clinical Pathologists; 2012. 

Keebler CM, Somrak TM, eds. The Manual of Cytotechnology, 7th ed. Chicago, IL: American Society of Clinical Pathologists; 1993.

Kurman RJ, ed. Blaustein’s Pathology of the Female Genital Tract, 6th ed. New York, NY: Springer-Verlag; 2001.

Mahon CR, Manuselis G Jr, eds. Textbook of Diagnostic Microbiology, 2nd ed. Philadelphia, PA: W.B. Saunders Company; 1995.

McClatchey KD, ed. Clinical Laboratory Medicine, 2nd ed. Baltimore, MD: Williams & Wilkins; 2002.

Solomon D, Nayar R. The Bethesda System for Reporting Cervical Cytology: Definitions, Criteria and Explanatory Notes, 2nd ed. New York, NY: Springer-Verlag; 2004.

Wilbur DC, Henry MR. College of American Pathologists Practical Guide to Gynecologic Cytopathology: Morphology, Management and Molecular Methods. Chicago, IL: College of American Pathologists; 2008.

American Cancer Society. Cervical Cancer. cancer (accessed 11/22/13)

American College of Obstetricians & Gynecologists. (accessed 11/22/13)