This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Carcinoma Cervix, Subject name: Gynaecology & Obstetrics
Patient diagnosed as squamous cell intraepithelial lesion which of the following has the highest risk for progression to carcinoma: 
Select and explain. 
A. Low grade squamous intraepithelial neoplasia, B. High grade squamous intraepithelial neoplasia, C. Squamous intraepithelial associated with HPV 16, D. Squamous intraepithelial neoplasia associated with HIV
B: High grade squamous intraepithelial neoplasia
Answer: B: High grade squamous intraepithelial neoplasia 
Explanation: Ans. is b, i.e. High grade squamous intraepithelial neoplasiaRef: Shaw 15th/ed, p402; Williams Gynae 1st/ed, p629There are various nomenclatures/classification systems for reporting of Pap smear.The one which is classically used is by WHO, which uses the terms CIN-I, CIN-II and CIN-IIIAnother system as discussed earlier is Bethesda which classified the disease as LSIL=low grade squamous intraepithelial lesion and HSIL high grade squamous intraepithelial lesion and chances of progressing to cancer are maximum with HSIL which includes CIN11, CIN111 and ca in situ.