squamous intraepithelial lesion

squamous intraepithelial lesion An abnormal growth of the squamous cells that normally are found on the uterine cervix. Abbreviated SIL. The changes are described as low grade (LGSIL) or high grade (HGSIL), depending upon how abnormal the cells look. Squamous intraepithelial lesions can be a precursor of cervical cancer; treatment of high grade SIL is by removal of the affected tissue.