skip to main content
skip to main content
MSDMerck ManualProfessional Version
Search icon

Bethesda Classification of Cervical Cytology*

Category

Specifics

Comments

Specimen type

Conventional (Papanicolaou [Pap] test), liquid-based preparation, or other

Type of test is noted.

Adequacy of the specimen

Satisfactory for evaluation

Any quality indicators (eg, presence or absence of endocervical/transformation zone component, partially obscuring blood, inflammation) are described.

Unsatisfactory for evaluation (rejected and not processed)

Reason is specified.

Unsatisfactory for evaluation but processed and evaluated

Reason is specified.

General categorization (optional)

Negative for intraepithelial lesion or cancer

Epithelial cell abnormalities

Other findings

Findings are stated or described under Interpretation, below.

Interpretation of negative (nonmalignant) abnormalities†

Organisms

Possible findings include the following:

  • Trichomonas vaginalis

  • Fungi morphologically consistent with Candida species

  • Shift in vaginal flora suggesting bacterial vaginosis

  • Bacteria morphologically consistent with Actinomyces species

  • Cellular changes consistent with herpes simplex virus

  • Cellular changes consistent with cytomegalovirus

Nonneoplastic findings (reporting is optional)

Possible findings include the following:

  • Nonneoplastic cellular variations (squamous metaplasia, keratotic changes, tubal metaplasia, atrophy, or pregnancy-associated changes)

  • Reactive cellular changes associated with inflammation (lymphocytic cervicitis), radiation, or IUD use

  • Glandular cell status after hysterectomy

Interpretation of epithelial cell abnormalities

Squamous cell

Possible findings include the following:

  • Atypical squamous cells of undetermined significance (ASC-US)

  • Atypical squamous cells for which a high-grade lesion cannot be excluded (ASC-H)

  • Low-grade squamous intraepithelial lesion (LSIL) encompassing HPV‡ infection or mild dysplasia (CIN 1)

  • High-grade squamous intraepithelial lesion (HSIL) encompassing moderate (CIN 2) and severe dysplasia (CIN 3/CIS), noting whether the lesion has features suggesting invasion

  • Squamous cell carcinoma

Glandular cell

Possible findings include the following:

  • Atypical cells: Endocervical, endometrial, or glandular; NOS or specify in comments

  • Atypical cells: Endocervical or glandular; favor neoplastic

  • Adenocarcinoma in situ: Endocervical

  • Adenocarcinoma: Endocervical, endometrial, extrauterine, or NOS

Interpretation of other abnormalities

Endometrial cells (in a woman > 45)*

Whether sample is negative for squamous intraepithelial lesion is specified.

Other cancers

—

Type is specified.

* Use of an automated device for scanning should be reported, as should adjunctive tests (eg, HPV) and their results.

† If there is no cellular evidence of neoplasia, the report should state negative for intraepithelial lesion or malignancy here or in the general categorization.

‡ Cellular changes of HPV infection—previously called koilocytosis, koilocytotic atypia, and condylomatous atypia—are included in the category of low-grade squamous intraepithelial lesion.

CIN = cervical intraepithelial neoplasia; CIS = carcinoma in situ; HPV = human papillomavirus; IUD = intrauterine device; NOS = not otherwise specified.

Adapted from the Bethesda System 2014, National Institutes of Health.

In these topics