High-Grade Squamous Intraepithelial Lesions (HSIL) are significant cellular changes detected on the cervix. While not cancer, HSIL indicates abnormal cells that could develop into cancer if untreated. This article explains what HSIL means and how it is typically managed.
Understanding High-Grade Squamous Intraepithelial Lesions
HSIL involves abnormal cell growth on the surface of the cervix, typically identified through a Pap test. Under a microscope, HSIL cells appear moderately to very abnormal compared to healthy cells.
HSIL development is strongly linked to persistent infection with high-risk Human Papillomavirus (HPV) types, such as HPV 16 and 18. HSIL encompasses conditions previously known as cervical intraepithelial neoplasia grades 2 and 3 (CIN 2 and CIN 3), and moderate and severe dysplasia.
HSIL: Not Cancer, But a Precursor
HSIL is not cancer but a serious precancerous condition, involving abnormal cell changes that can progress to invasive cervical cancer if not managed. In about 2% of HSIL diagnoses, underlying invasive cervical cancer may already be present, detected upon further investigation like a colposcopy.
If untreated, HSIL can progress to invasive cancer in about 2% of cases. Follow-up and treatment are important to prevent this progression and significantly reduce the risk of developing cervical cancer.
Next Steps After an HSIL Diagnosis
After an HSIL diagnosis, a colposcopy is typically performed to evaluate the cervix. A healthcare provider uses a magnifying instrument to examine the cervical surface and identify suspicious areas. Targeted biopsies are then taken for a definitive diagnosis.
Common treatment options remove abnormal cells and prevent progression. The Loop Electrosurgical Excision Procedure (LEEP) uses a heated wire loop to remove affected tissue. Cryotherapy, which freezes and destroys abnormal cells, is another option. Consistent follow-up and surveillance are essential after treatment to ensure abnormal cells do not return.
Influences on HSIL Progression
Several factors influence whether HSIL progresses to invasive cancer or regresses. Persistent infection with high-risk HPV types is the primary driver of HSIL progression. A weakened immune system, which plays a significant role in clearing HPV infections, can also increase this risk.
Smoking, both active and passive, increases the risk of HSIL progression. Early sexual activity and multiple sexual partners also contribute by increasing HPV exposure. Regular screening and adherence to recommended treatments are important in preventing HSIL from advancing to cervical cancer.