Do all grade I lesions on colposcopy need to be biopsied?

The present study intends to correlate grade I atypical transformation zone (ATZ) on colposcopy with cytology & histology in 51 patients by retrospective data analysis. Indications of colposcopy were inflammatory smears with unhealthy cervix (37/51). Atypical squamous cells of unknown etiology (2/51) & squamous intraepithelial lesions on cytology (12/51). All the patients exhibited grade I lesions on colposcopy & underwent directed biopsy. On histology chronic cervicitis was the commonest finding 70.6% (36/51) & CIN was found in 19.6% (10/51), out of which CIN II-III occurred only in 3.92% (2/51). Overcall rate of colposcopy for grade I lesions was 80.39%. Age, parity, the postcoital or contact bleeding did not correlate with the histological positivity of the lesions. Grade I ATZ with inflammatory smears revealed CIN II-III only in 2.7% (1/37) while with low grade SIL cytology there was no moderate or severe dysplasia. However Grade I lesions in association with high grade SIL exhibited CIN II-III lesions in 16.6% (1/6). Therefore grade I lesions in presence of inflammatory or low grade SIL smears can be observed & biopsied only if the changes persist. However association of high grade SIL with grade I ATZ calls for immediate biopsy.