[Comment on Diagnosis of Atypical Squamous Cells Using New the Bethesda System 2001]

Objective: To evaluate the criteria for diagnosis of atypical squamous cells (ASC) and its two subtypes: undetermined significance ASC (ASC-US) and atypical squamous cells-cannot exclude high-grade intraepithelial lesion (HSIL, ASC-H) defined in 2001 the Bethesda system (TBS).

Method: One thousand one hundred and eighty six pap smears and liquid-based thin-layer preparations with diagnosis of atypical squamous cells of undetermined signification (ASCUS) according to TBS 1991 criteria, were re-classified by a cytopathologist using TBS 2001 criteria.

Results: The cytologic diagnosis according to TBS 2001 criteria was: negative in 285 cases (24.0 %), ASC-US in 627 cases (52.9%), ASC-H in 254 cases (21.4%), low-grade intraepithelial lesion (LISL) in 16 cases (1.3%), and HISL in 4 cases (0.3%), respectively. Out of 1186 cases, 168 received histological examination. Cervical intra-epithelial neoplasia (CIN) II-III were diagnosed in 18.9 % of patients with ASC-H, 5.2% of patients with ASC-US, and 14.3% of patients with ASCUS defined by using TBS 1991 criteria, respectively (P < 0.05). During the follow-up of 6 months, 4 cases of ASC-US changed to LSIL, one ASC-US changed to HSIL, 2 ASC-US changed to LSIL, and 2 ASC-US to HSIL.

Conclusions: New classification of ASC recommended by 2001 TBS has apparent clinical significance. Colposcopically directed cervical biopsy should be performed immediately if ASC-H is diagnosed. In ASC-US patients, checking of cervical smear in an interval of 3 approximately 6 months is necessary. It is suggested to use ASC-US and ASC-H instead of ASCUS in cytological diagnosis.