In this study, we analyzed the distribution of the incidence and genotypes of HPV among women with cervical lesions in Yueyang City, China, with an aim to develop prevention and control strategies for CC in the region. We found that the incidence of HPV infection among women with cervical lesions in Yueyang City was very high, and HPV 16, 52, 58, 53, and 51 were the five most common HPV genotypes among these patients.
The most common HPV genotypes in Asia are HPV 16, HPV 52, HPV 58, HPV 18, and HPV 56[15]. In China, there are differences in HPV infection types among different cities, with the most common genotypes being 52, 58, 16, and 51 in Zhejiang; 16, 52, 58, 53, and 31 in Xinjiang; and 16, 58, 52, 51, and 54 in Shanghai [12, 16, 17]. In the present study, we investigated the prevalence of HPV in 3674 patients with cervical lesions in Yueyang City, and the most common HPV genotypes were HPV 16, 52, 58, 53, and 51.
Persistent HPV infection leads to the development and progression of cervical lesions and CC. In the present study, the incidence of HPV infection in patients with CIN I, CIN II, CIN III, and ICC was 66.65%, 80.78%, 83.88%, and 86.81%, respectively. Li et al. [18] reported that the prevalence of HPV infection in CIN I, CIN II+, and CC samples was 59.6%, 84.8%, and 89.9%, respectively. In another study, Lei et al. [19] investigated 1664 female patients and found that HPV positivity in these patients increased directly with the severity of cervical lesions (72.4% for CIN I, 81.4% for CIN II, 88.1% for CIN III, and 90.4% for ICC), There are many similar studies [20, 21]. The consistency of these data suggests that HPV positivity increases with the severity of cervical lesions. The overall incidence of HPV in patients with ICC in this study was 86.81%, which is consistent with the global incidence of HPV in CC patients (86–94%) [22].
In the present study, HPV 52, 16, and 58 were found to be the major contributors to CIN I and II, and HPV 16, 58, and 52 were the major contributors to CIN III and ICC, Similar to Shanxi Province [20], Distinguish from Jiangsu and Sichuan [14, 23]. On the whole, these findings are similar to those of previous domestic and international studies. HPV 16 was the predominant subtype, with an incidence of 12.57%, 20.89%, 36.98%, and 50.85% in the CIN I, CIN II, CIN III, and ICC groups, respectively. The incidence increased with the severity of cervical lesions, with HPV 16 being predominant.
HPV 52 is the most prevalent genotype [16, 24–26] in many regions of China and is a major contributor to CC. However, among the 3674 patients in our study, HPV 52 was most common in low-grade squamous intraepithelial lesions of the cervix, specifically ranking first in prevalence in the CIN I and CIN II groups (incidence of 19.84% and 26.74%, respectively) and ranking third in prevalence in the CIN III and ICC group (incidence of 17.19% and 14.68%, respectively). In contrast, HPV 58 ranked third in the CIN I and CIN II groups (incidence of 10.37% and 18.94%, respectively) and second only to HPV 16 in the CIN III and ICC groups (incidence of 22.57% and 15.32%, respectively). These findings are consistent with those of a study of HPV genotype distribution among 7747 women in South Sichuan [27] and 40311 women in southwest China [28]. Therefore, our findings suggest that HPV 58 is the most oncogenic subtype other than HPV 16 in the Yueyang region. However, among the three vaccines, only the 9-valent vaccine covers HPV 58 and few women received the 9-valent vaccine, emphasizing the importance of vaccinating women in the Yueyang region with the 9-valent vaccine.
HPV 18 has been shown to be the second most common genotype worldwide [29, 30]; however, it had a lower incidence in this study (5.65%, 5.71%, and 2.95% in the CIN I, CIN II, and CIN III groups, respectively; all ranking above fifth, and 5.74% in ICC patients, ranking fourth). Previous studies have suggested that the incidence of HPV 18 infection may be associated with higher rates of adenocarcinoma [31]; however, very few cases in the present study were classified as cervical adenocarcinoma, and further validation of the results in a large-sample study is still required.
Age is one of the most important factors influencing HPV infection, and in the present study, HPV infection in high-grade squamous intraepithelial lesions (CIN II and III) was noted in patients aged 40–49 years. This finding was similar to that in studies from Taizhou and Jiangsu provinces [14, 32]. The age group with the highest prevalence of HPV in the ICC group was the ≥ 60 years group(incidence: 46.17%); this incidence was higher than that in the 50–59 years age group in a study from Taizhou [14], higher than that in the 40–44 years age group in a study from Shanghai and Zhejiang [33], and higher than that in the 41–50 years age group in a study from Jiangsu [32]. This may be related to the increasing attention to CC prevention and treatment in Yueyang; however, the small sample size in the present study cannot be neglected. HPV 16 was the most common genotype across all age groups in the CIN III and ICC groups, except for that in the ≥ 60 years age group in the CIN III group (ranking the second highest in this study). However, in the CIN I and II groups, the most common genotype was HPV 52 across almost all age groups. This result again suggests that the incidence of HPV 16 increases with the increasing severity of cervical lesions.
In conclusion, HPV subtypes are distributed differently in different regions, and the data from the present study support the use of preventive HPV vaccines in Yueyang. In addition, this study provides important basic data for the prevention and surveillance of HPV infection in the region, which is important for clinical prevention and treatment of CC, prediction of lesion progression, and assessment of outcomes.