Prevention of Cervical Neoplasia and Carcinoma

PREVENTION

Preventive approaches to cervical cancer include sexual abstinence, the use of barrier protection with or without spermicides, regular gynecologic examination and cyto-logic screening with treatment of precancerous lesions according to established protocols, and vaccination with the HPV vaccine. It is estimated that gynecologic exami-nation and Pap tests administered according to current guidelines may reduce cancer incidence and mortality by 40%. Limiting the number of sexual partners also may decrease one’s risk for STDs, including HPV.

The recently developed HPV vaccine prevents trans-mission and acquisition of type-specific HPV through sex-ual and nonsexual contact. Currently, the only approved vaccine on the market is active against oncogenic HPV types 16 and 18 as well as two types that cause genital warts, HPV types 6 and 11. Another vaccine currently being investigated is active against oncogenic HPV types 16 and 18. These two vaccines contain virus-like particles (VLPs) that consist of the main structural HPV-L1 protein but lack the viral genetic material and, hence, are non-infectious. These vaccines stimulate production of IgG-type specific antibodies to prevent acquisition of type specific HPV in the genital and vulvar areas. The quadrivalent vaccine has been shown to prevent 91% of new and 100% of persistent infections. Currently, HPV vaccines are only indicated for prophylaxis (Box 43-4). However, it is antic-ipated that the guidelines for their use will continue to change regarding age group, sex, and therapeutic indica-tions. The development of new vaccines may also broaden the horizon for HPV treatment.