Prevalence and Genotyping of HPV in Different Grades of Cervical Intraepithelial Neoplasia and Cervical Cancer

Abstract

Objective : Our purpose was to evaluate the prevalence and genotypic distribution of HPV infection by newly developed HPV DNA chip in various cervical lesions and to assess the relationship between HPV genotypes and different grades of cervical intraepithelial neoplasia (CIN) and cervical cancer. Methods : Between December 2001 and May 2003, 394 patients who visited Busan Paik hospital due to abnormal Pap smear or colposcopic finding, were involved and classified into 5 groups according to their cytologic diagnoses: nonspecific chronic cervicitis (n=36), ASCUS/AGUS (n=36), LSIL (n=46), HSIL (n=131), cervical cancer (n=145). We examined HPV positivity and genotype of the specimens using HPV DNA chip, which detects 22 HPV genotypes including 15 high-risk HPV groups (16/18/31/33/35/39/45/51/52/56/58/59/66/68/69) and 7 low-risk HPV groups (6/11/34/40/42/43/44). Results : The overall detection rate of HPV infection was 71.1% (280/394), and the detection rate of high-risk HPV infection was 67.0% (264/394). According to the grade of the lesions, the detection rates of high-risk of HPV infection were 19.4% (7/36) in nonspecific chronic cervicitis, 16.7% (6/36) in ASCUS/AGUS, 63.0% (29/46) in LSIL, 83.2% (109/131) in HSIL, and 77.9% (113/145) in cervical cancer. The major prevailing HPV genotypes in this study were HPV types 16, 58, 18, 35, and 52 in descending order of incidence, which averaged 86.7% for all. HPV 16 was the most common type in all the HPV-positive cases as well as HSIL and cervical cancer. HPV 18 was the second most common type in cervical cancer and HPV 58 was the second most common type in HSIL. The odds ratio was estimated to evaluate the relationship of HSIL and cervical cancer versus HPV type. HPV 16 and 35 were found to be significantly related to HSIL, cervical cancer, or HSIL and cervical cancer. HPV 58 was found to be significantly related to HSIL, or HSIL and cervical cancer. Conclusion : In our study, HPV type 16, 18, 35, 52, and 58 were confirmed to be major prevailing subtypes in CIN and cervical cancer. Our results suggest that HPV 16, 35, and 58 positive patients have a tendency to develop HSIL and cervical cancer than other HPV positive patients.