Aim: To determine the prevalence of high-grade cervical lesion (CIN 2 or worse, CIN 2+) and the prevalenceof invasive cancers in women with LSIL, HSIL and positive for malignancy on cytology, respectively.
Methods: A retrospective study of patients undergoing colposcopy in Rajavithi hospital between 2003-2004was performed. The final diagnosis was based on colposcopy and histology.
Results: Among 250 women withLSIL and 152 women with HSIL, 28 (11.20%) and 112 (75.70%), respectively, had histology-confirmed highgradecervical lesions. Invasive cancer was diagnosed in 12 (7.9%) of women with HSIL but in none of the LSILcases. Among 19 women with positive smears for malignancy, only 7 ( 36.8 % ) had histology-confirmedinvasive cancer.
Conclusion: The present study confirms that women with HSIL have high prevalence ofhigh-grade cervical lesions and malignancy. Women with LSIL may be managed less aggressively because of thenegligible risk of more advanced lesions. Smears positive for malignancy are inconsistent predictors of invasivecancer.