What are the recommended diagnostic tests for cervical cancer screening in a colposcopy (colposcopy) lab, including Human Papillomavirus (HPV) DNA testing and Pap smear?

Diagnostic Tests for Colposcopy Screening Labs

Primary Screening Tests

For cervical cancer screening in a colposcopy lab, the essential diagnostic tests are cervical cytology (Pap test) and high-risk HPV DNA testing, with specific age-based protocols determining which tests to use and when. 1

Cervical Cytology (Pap Test)

• Liquid-based cytology is preferred over conventional cytology as it allows for reflex HPV testing from the same specimen and improves detection of glandular abnormalities 1
• Results are reported using the 2001 Bethesda System terminology: negative, ASC-US, LSIL, ASC-H, HSIL, atypical glandular cells (AGC), or invasive carcinoma 1
• Screening intervals: every 3 years for women aged 21-29 years with cytology alone, or every 5 years for women aged 30-65 years with cotesting (cytology plus HPV) 1

High-Risk HPV DNA Testing

• FDA-approved tests detect 13-14 high-risk HPV types including HPV 16,18,31,33,35,39,45,51,52,56,58,59,66, and 68 1
• Available FDA-approved tests include Hybrid Capture 2 High-Risk HPV DNA test and Cervista HPV High-Risk test 1
• HPV testing should NOT be used as a stand-alone screening test - it must be combined with cytology or used for specific triage situations 1

Age-Specific Testing Protocols

Women Under 21 Years

• No screening recommended - neither cytology nor HPV testing should be performed 1

Women Aged 21-29 Years

• Cytology alone every 3 years is the standard approach 1
• HPV testing is NOT recommended for routine screening in this age group due to high HPV prevalence and frequent spontaneous clearance 1
• HPV testing is acceptable only for triage of ASC-US results (reflex testing) 1, 2

Women Aged 30-65 Years

• Cotesting (cytology plus HPV) every 5 years is preferred over cytology alone 1
• Alternative: cytology alone every 3 years if cotesting unavailable 1
• For women with normal cytology and negative HPV, screening interval extends to 3 years 1

Specific Clinical Indications for HPV Testing

Triage of ASC-US Results

• Reflex HPV DNA testing is the preferred triage method for women ≥21 years with ASC-US cytology 1, 2
• If HPV positive: refer for colposcopy 1, 2
• If HPV negative: repeat cytology at 12 months 1, 2
• Sensitivity of HPV testing for detecting CIN 2+ in ASC-US cases is approximately 90% with specificity of 54% 3

Adjunct Screening in Women ≥30 Years

• HPV testing combined with cytology increases sensitivity for detecting high-grade lesions to 88-91% compared to 61% for cytology alone 4
• Negative cotesting (both cytology and HPV negative) allows for 3-year screening intervals 1

Post-Colposcopy Follow-Up

• HPV DNA testing at 12 months is recommended for women with ASC-US or LSIL who had negative colposcopy findings 1
• Alternative: repeat cytology at 6 and 12 months 1

Tests NOT Recommended for Colposcopy Labs

Inappropriate Uses of HPV Testing

• Do NOT use HPV testing in women <21 years for any indication 1
• Do NOT use low-risk HPV testing - only high-risk types are clinically relevant 1
• Do NOT use HPV testing to decide on HPV vaccination 1
• Do NOT use HPV 16/18 genotyping for initial triage of ASC-US - all high-risk HPV positive patients should proceed to colposcopy 1
• Do NOT use HPV testing for STD screening 1

Additional Diagnostic Procedures During Colposcopy

Colposcopic Examination

• Cervix viewed through colposcope at 10x-16x magnification after application of 3-5% acetic acid solution 1, 2
• Directed biopsies taken from acetowhite lesions or abnormal vascular patterns 1

Endocervical Curettage (ECC)

• Preferred for women with no visible lesions on colposcopy 1
• Required for women with unsatisfactory colposcopy (transformation zone not fully visualized) 1
• Acceptable for women with satisfactory colposcopy and identified transformation zone lesions 1
• Contraindicated in pregnancy 1

Endometrial Sampling

• Required for all women ≥35 years with atypical glandular cells (AGC) 1
• Required for women <35 years with AGC who have unexplained vaginal bleeding or chronic anovulation 1
• Required for women with atypical endometrial cells regardless of age 1

Common Pitfalls to Avoid

• Do not perform annual screening - it is not recommended for any age group 1
• Do not equate pelvic examination with Pap test - many women mistakenly believe a Pap was obtained during routine pelvic exam when it was not 1
• Do not use diagnostic excisional procedures (LEEP, cone biopsy) without histologic confirmation of CIN 2/3 1, 2
• Do not rely on patient self-report of recent Pap test results - verify with clinical documentation 1
• Do not screen women who have had adequate prior screening and are ≥65 years with three consecutive negative cytology results in past 10 years 1

Quality Control Requirements

• All cytopathology and HPV DNA testing must be performed in CLIA-certified laboratories 1
• Cytopathology results must use Bethesda 2001 terminology 1
• Protocols must be in place for follow-up of abnormal results and case management 1