The Clinical Significance of The Qualification of Atypical Squamous Cells of Undetermined Significance (ASCUS) in Cervicovaginal Smears

Jo, Mi Yeong; Park, Young Han; Ryu, Hee Sug; Joo, Hee Jae; Lee, Won Jong; Chang, Ki Hong; Lee, Jung Pil; Oh, Kie Suk

Abstract

OBJECTIVE
The Bethesda System (1991) recommended that the diagnosis of atypical squamous cells of undetermined significance (ASCUS) be qualified when possible to indicate whether a reactive process, or premalignant/malignant process, is favored. In order to evaluate the clinical significance of the qualification, we reviewed our hospital's experience with cervicovaginal smears diagnosed as ASCUS. METHOD: A retrospective study from June 1994 to December 2000 was performed on all cervicovaginal smears with the diagnosis of ASCUS. 3759 cases were included in study group. The 1200 cases of 3759 were not followed up. Histopathologic diagnosis and cervicovaginal smear results were reviewed and compared according to the qualification of ASCUS. The Chi-square test was used.
RESULTS
Histopathologic diagnosis of low-grade squamous intraepithelial lesion (LGSIL) was seen in 46.1%, 47.8%, and 44.3% of the ASCUS FR, ASCUS FD and ASCUS NOS group, respectively. Histopathologic diagnosis of high-grade squamous intraepithelial lesion (HGSIL) was seen in 6.0%, 17.2% and 7.8% of the ASCUS FR, ASCUS FD and ASCUS NOS group, respectively. In ASCUS FR group, 1 invasive carcinoma was detected. In ASCUS FD group, 6 carcinoma in situ (CIS), 2 microinvasive carcinoma, 1 invasive carcinoma and 1 adenosquamous cell carcinoma were detected. In ASCUS NOS group, there were 20 CIS, 5 microinvasive carcinoma, 7 invasive carcinoma and 2 invasive adenocarcinoma. The ASCUS FD group demonstrated significant risk for SIL and more severe lesion but ASCUS FR and ASCUS NOS demonstrated no significant difference.
CONCLUSION
ASCUS FD group has increased risk for detection of SIL or more severe lesion than ASCUS FR or ASCUS NOS group. But there were also significant number of SIL and even invasive cancer in ASCUS FR and ASCUS NOS group, so qualification of ASCUS was not useful for management and colposcopy-directed biopsy is advocated even in ASCUS FR group.