What is the follow-up for a 27-year-old with Atypical Squamous Cells of Undetermined Significance (ASC-US) with a negative Human Papillomavirus (HPV) test result?

From the Guidelines

For a 27-year-old with ASC-US (Atypical Squamous Cells of Undetermined Significance) and negative HPV testing, the recommended follow-up is to repeat co-testing with both cytology and HPV testing in 3 years. This recommendation is based on the most recent guidelines from the American Society for Colposcopy and Cervical Pathology, as outlined in the 2021 study 1. The negative HPV result significantly reduces the risk of developing cervical cancer or high-grade precancerous lesions, and the combination of ASC-US with negative HPV indicates a low risk situation. According to the guidelines, women with an HPV-negative ASC-US result should return for screening in 3 years, rather than 5 years, to ensure continued surveillance.

Key Points to Consider

• The absence of high-risk HPV types in the presence of ASC-US is reassuring, as HPV is the causative agent in virtually all cervical cancers.
• No immediate colposcopy or more frequent testing is needed in this scenario, as the risk of developing cervical cancer or high-grade precancerous lesions is low.
• It is essential that the patient returns for the recommended follow-up in 3 years to ensure continued surveillance, as HPV infections can be acquired later.
• If future screenings show persistent ASC-US or positive HPV, more intensive follow-up would then be warranted, as outlined in the guidelines 1.

Rationale for Recommendation

The recommendation to repeat co-testing in 3 years is based on the principle of similar management of similar risks, as outlined in the 2015 study 1. The risk of CIN3 and of cancer is greater after a negative Pap test compared with that after a negative cotest, and is even higher for women with an HPV-negative ASC-US result, although it should be noted that all of these risks are very low. The 2021 guidelines 1 provide the most up-to-date recommendations for managing abnormal cervical cancer screening tests and cancer precursors, and should be followed in clinical practice.

Clinical Implications

In clinical practice, it is essential to follow the recommended guidelines for managing abnormal cervical cancer screening tests, including ASC-US with negative HPV testing. The recommended follow-up of repeating co-testing in 3 years should be communicated to the patient, along with the rationale for this recommendation. Patients should be encouraged to return for follow-up screening as recommended, to ensure continued surveillance and early detection of any potential abnormalities.

From the Research

Follow-up for ASC-US with Negative HPV Test Result

• A 27-year-old with Atypical Squamous Cells of Undetermined Significance (ASC-US) and a negative Human Papillomavirus (HPV) test result can be managed according to the current guidelines 2, 3.
• The American Society for Colposcopy and Cervical Pathology (ASCCP) guideline recommends a repeat Pap smear in the next 1 year for women with ASC-US and a negative HPV test result 2.
• A study found that high-risk HPV testing for women with ASC-US is useful in determining the risk for precancerous and cancerous cervical lesions, and a negative result is associated with a low risk for cervical lesions 3.
• Another study suggested that women with ASC-US and a negative HPV test result have a low risk of developing cervical abnormalities, and co-testing (combination of cervical cytology and high-risk HPV testing) is an optimal method to identify patients with higher risk for developing cervical abnormalities 4.
• However, it is essential to note that the management of ASC-US with a negative HPV test result may vary depending on individual risk factors and medical history, and colposcopy may be recommended for women with high-risk factors or persistent ASC-US 2, 5.

Risk Factors and Colposcopy Referral

• High-risk factors for persisted abnormal Pap smears in subsequent tests include premenopausal status, HIV-infected patients, and non-oral contraceptive pills (COC) users 2.
• The colposcopic referral rate was 23.2% at 12 months in a study of women with ASC-US, and the prevalence of cervical intraepithelial neoplasia (CIN) 2/3 was 3.3% 2.
• A study found that HR-HPV testing plays an important role in cervical cancer screening by identifying HSIL in patients with ASC-US, LSIL, and NILM, and co-testing is an optimal method to identify patients with higher risk for developing cervical abnormalities 4.