Document Type: Research Articles
Department of Obstetrics and Gynecology, Faculty of Medicine, HRH Princess Maha Chakri Sirindhorn Medical Center (MSMC), Srinakharinwirot University, Nakornnayok, Thailand.
Department of Obstetrics and Gynecology, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Bangkok, Thailand
Objective: The aim of this study was to compare the efficacy of HPV 16/18 genotyping test, high risk HPV DNA testing, alone and in conjunction with the liquid-based cytology method in screening for cervical cancer precursors. Methods: A Markov model was used to describe the course of the cases of CIN2+ that had been detected over a 35 year period. Screening programs started at age 30 and were performed at an interval of once every five years. The model compared three strategies of HPV 16/18 genotyping with reflex cytology triage, high-risk HPV testing alone with referral to colposcopy and cytology-based screening with referral to colposcopy. We assumed the rate of patients lost to follow-up for those referred to colposcopy would be 0%. The clinical parameters were estimated using the data from a study conducted by the Thailand National Cancer Institute. Result: Of the three screening strategies evaluated, the high risk HPV DNA testing alone was the most effective for detecting CIN2+ over the 35 year study period. It detected 143 and 510 cases per 100,000 women more than the HPV 16/18 genotyping test and cytology-based strategy, respectively. The HPV genotyping test detected 368 cases per 100,000 women more than the cytology-based approach. In addition, when viewed with five year intervals, there were missed cases totaling approximately half of the detected cases screened by the cytology strategy and 10% of cases detected with screening by the HPV genotyping test. Conclusion: This study strongly indicates that HPV/DNA testing is preferable to cytology-based screening for cervical cancer precursors. However, the balance between the benefits, burdens and cost of each screening program should be considered.