Prevalence of high grade squamous intraepithelial lesion (HSIL) and invasive cervical cancer in patients with low grade squamous intraepithelial lesion (LSIL) at cervical pap smear.

Objective: To assess the prevalence and factors associated with a histologic diagnosis of high grade squamous intraepithelial lesion (HSIL) and invasive cervical cancer in patients with low grade squamous intraepithelial lesion (LSIL) cervical pap smear findings.

Methods: Medical records (including cytology reports, colposcopic impression, and pathologic results from cervical biopsy, endocervical curetting, cervical conization or hysterectomy) of 226 women with LSIL from conventional cervical pap smears during January 2001 to December 2005, who subsequently underwent colposcopic evaluation at our institution, were reviewed.

Results: Mean age of the patients was 39.0 years. The incidences of LSIL, HSIL, microinvasive cervical cancer were 58.8%, 15.0%, 1.3% respectively. No associations were found between age, parity, contraception, anti-HIV or menstrual status and the detection of HSIL/invasive cervical cancer.

Conclusion: Approximately 16.3 % of LSIL pap smear cases turn out to be HSIL or invasive cervical cancer from histologic diagnosis.