 Through a consensus of management of patients with abnormal Pap smear in TGOG, a standard protocol of specimen collection, clinical follow-up has been established. Patients with a Pap smear of ASCUS, AGCUS or SIL will be arranged with a repeat Pap smear and a colposcopy with or without biopsy. A cervical swab will be taken and sent to the core laboratory for HPV DNA detection and genotyping. Pap smear and biopsies were then panel-reviewed by Pathologists. Cytology-or pathology-proved LSIL cases will be followed every three months with Pap smear, colposcopy and HPV test until disease progression or two consecutive negative results of all the three data. One thousand cases fulfilling aim 1 will be analyzed during the first year, and the nature course of about 300 LSIL cases will be followed at the end of the third year. 