Low Grade Squamous Intraepithelial Lesion/Cannot Exclude High Grade Squamous Intraepithelial Lesion (LSIL-H): A Unique Cytologic Abnormality
Stacey Barron, Zaibo Li, R Marshall Austin, Chengquan Zhao. Magee-Womens Hospital of University of Pittsburgh Medical Center, Pittsburgh, PA
Background: SIL of Indeterminate Grade was introduced in the 2001 Bethesda system. This term, or low grade squamous intraepithelial lesion, cannot exclude high grade squamous intraepithelial lesion (LSIL-H), has been used. Data about prevalence of hrHPV in women with LSIL-H and subsequent histopathology are limited.
Design: A search of CoPath files was performed to retrieve cases with a cytologic diagnosis of LSIL-H and concurrent hrHPV testing between 07/2005 and 12/2011. HrHPV testing and histologic follow-up results were recorded.
Results: 495 cases with a cytologic diagnosis of LSIL-H and concurrent hrHPV testing were identified. HrHPV was positive in 448 of 495 cases (90.5%). Patients' average age was 30 years old (range: 15-80, median: 27). Of 347 patients who had at least one subsequent histologic follow-up within an average period of 24 months (range: 6-66, median: 24), CIN2/3 was detected in 103 patients (29.7%) and CIN1 in 186 patients (53.6%). Of those 103 cases with a histologic follow-up of CIN 2/3, the median interval between LSIL-H and initial CIN2/3 diagnosis was about 3 months (range: 0.5-60). CIN2/3 was identified on histopathologic follow-up in a significantly greater proportion of women with hrHPV-positive LSIL-H than patients with hrHPV-negative LSIL-H (p<0.05). The hrHPV positivity data and histopathologic follow-up data are also compared to our published data in patients with LSIL, ASC-H, and HSIL from the same institution (Table 1).
|Category||HPV Positive Rate||CIN2/3||CIN1|
|HPV +||HPV -||HPV +||HPV -|
|LSIL-H||90.5%||99/321(30.8%)||4/26 (15.4%)||172/321 (53.6%)||14/26 (53.8%)|
|HSIL||95.7%||197/273 (72.2%)||4/12 (33.3%)||52/273 (19.1%)||5/12 (41.7%)|
|ASC-H||54.3%||84/257 (32.7%)||3/248 (1.2%)||76/257 (29.2%)||32/248 (12.9%)|
|LSIL||80.2%||89/612 (14.5%)||4/107 (3.7%)||357/612 (58.3%)||44/107 (41.1%)|