Inclusion Criteria:

          -  Women with biopsy confirmed high grade cervical squamous intraepithelial lesions
             (i.e., cervical squamous intraepithelial neoplasia 3 [CIN3] lesions, and cervical
             squamous epithelial neoplasia 2 [CIN2] lesions with diagnosis confirmed by positive
             p16 immunohistochemistry staining) within 12 weeks of baseline visit

          -  Karnofsky >= 70%

          -  Leukocytes >= 3,000/microliter

          -  Absolute neutrophil count >= 1,500/microliter

          -  Platelets >= 100,000/microliter

          -  Serum creatinine =< the upper institutional limits

          -  Participants must have a negative human immunodeficiency virus (HIV) antibody/antigen
             test and negative Chlamydia (C.) trachomatis/Neisseria (N.) gonorrhea nucleic acid
             amplification test (NAAT)

          -  Agree to use an effective form of contraception; the effects of intravaginal
             5-fluorocuracil and imiquimod on the developing human fetus at the recommended
             therapeutic dose are unknown; for this reason and because 5- fluorouracil is known to
             be teratogenic, women of child-bearing potential must agree to use adequate dual
             methods of contraception (hormonal method of birth control, intrauterine device, or
             tubal ligation - plus condoms) or abstinence prior to study entry and for the duration
             of study participation; should a woman become pregnant or suspect she is pregnant
             while participating in this study, she should inform her study physician immediately

          -  Ability to understand and the willingness to sign a written informed consent document

        Exclusion Criteria:

          -  Women treated previously with 5-fluorouracil or imiquimod or other medications for
             high-grade squamous intraepithelial lesions will be excluded from the study

          -  Concurrent vaginal, vulvar, anal lesions or symptomatic infections

          -  Pregnant or planning pregnancy within the next 6 months, or breastfeeding; pregnant
             women are excluded from this study because 5-fluorouracil is an antimetabolite with
             the potential for teratogenic effects; because there is an unknown but potential risk
             for adverse events (AEs) in nursing infants secondary to treatment of the mother with
             5-fluorouracil, breastfeeding should be discontinued if the mother is treated with
             5-fluorouracil

          -  Inability to speak or read English or Spanish

          -  Prior hysterectomy

          -  Use of anticoagulant medications

          -  Subjects who have a known immunocompromised condition (HIV positive [+], use of
             immunosuppressive medications or systemic steroids, organ transplant recipients) or
             autoimmune conditions (e.g. psoriasis, rheumatoid arthritis or other known autoimmune
             conditions)

          -  Evidence of invasive anal, vulva, vaginal, or cervical carcinoma; prior loop
             electrosurgical excision procedure (LEEP) or ablative treatment within 6 months prior
             to study entry; other invasive malignancies, with the exception of non-melanoma skin
             cancer, within the last 5 years

          -  Pathologic findings consistent with

               -  Atypical endometrial cells or serious glandular-cell atypia (atypical glandular
                  cells, favor neoplasia cytology diagnosis)

               -  Evidence of cervical carcinoma on Pap smear or biopsy

               -  More than two cervical quadrants of CIN 3 as visualized by colposcopy

               -  Nonvisual squamous columnar junction on colposcopy with no concurrent
                  endocervical sampling performed

          -  Use of other investigational agents within 6 months prior to enrollment

          -  History of allergic reactions attributed to compounds of similar chemical or biologic
             composition to 5-fluorouracil or imiquimod

          -  Uncontrolled intercurrent illness including, but not limited to, ongoing or active
             infection (other than human papilloma virus [HPV]), symptomatic congestive heart
             failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social
             situations that would limit compliance with study requirements

          -  Subjects with known partial or complete dihydropyrimidine dehydrogenase (DPD) enzyme
             deficiency