In-depth analysis of the controversy of HPV quantification

Research on HPV quantification can be traced back to 1991, but until now, it has not been included in any clinical guidelines. The main reason is that in the past 30 years, there have been many inconsistencies in the results of different studies.

In 2007, "Nature Reviews Cancer" 1 (impact factor 69.8) and "Lancet Oncology" 2 (impact factor 54.4), two major reviews of the world's top journals, clearly pointed out that HPV quantification has no clinical value. Although 15 years have passed, about HPV There are also many quantitative clinical studies, but the editor did not find a review on HPV quantification in the world's top journals. Questions about HPV quantification raised in two reviews in 2007 have not been well answered so far.

No matter what technology

HPV quantification has always failed to explain the two core mechanistic problems

With the higher the degree of lesions, the higher the proportion of virus integration, the virus replication decreased.

In terms of the biological mechanism of the virus, the 2017 National Institutes of Health (NIH) review on viral integration 3 (impact factor 7.464) pointed out three stages of the HPV virus life cycle:

During early infection of basal cells, the virus replicates with free circular DNA at low copy levels

As basal cells differentiate, the virus replicates in large numbers with free circular DNA

The virus integrates, the life cycle of the virus ends, it can no longer replicate, packaged into circular DNA, and infects a new host.

A review in Nature Reviews Cancer1 states that "the status of HPV integration increases with disease severity, but integration is followed by a reduction in viral load." A review in Lancet Oncology2 mentions that "some of the highest The viral load can be attributed to recently acquired mild lesions that produce large amounts of virus, similar to benign warts."

Heterogeneity of lesion tissue in the same patient--HPV quantification and tissue diagnosis are not equal

"The Lancet Oncology"1 review mentioned: "HPV quantification is a complex sum of lesions of different grades, different sizes, and different numbers of lesions in the same patient, and the meaning of viral load is not clear." "Nature Reviews Cancer"2 also mentioned that " In women with high-grade lesions, viral loads were higher when low-grade lesions were present; in the vast majority of studies, only the most severe tissue lesions were reported.”

Even with cell counting methods

Research results are still inconsistent

In addition to the widely accepted positive correlation between the quantification of HPV type 16 and lesions, the relationship between the quantification of other types and lesions is still controversial.

HPV quantification

Scientific value or clinical value?

A large number of medical researches are published every day all over the world, and some new laws are discovered, most of which are difficult to carry out in clinical practice, or have limited value compared with other programs in clinical practice, so these discovered laws are only It has scientific research value and cannot be included in clinical guidelines. Only those programs that bring greater clinical benefit compared to the current clinical pathway have real clinical value. Let the editor take a look at their real clinical value from a series of perspectives of HPV quantification:

1. "There is a positive regularity between quantitative results and lesion severity of HPV type 16 monoinfection". Clinical Value?

The above-mentioned study of 73,596 cases in the Obstetrics and Gynecology Hospital of Fudan University 6 (impact factor 3.464) showed that the median quantification of HPV16 did increase with the severity of the disease (box plot below), but the figure also The range of upper and lower limits of quantification showing different lesions is very wide, and the results fluctuate greatly. The US FDA emphasizes that all HRHPV tests used in clinical use need to have a clinical cut-off value for HSIL+ to reduce the detection of benign lesions. We use the lower limit of HSIL+ as the clinical cut-off value (red line). Above this, the quantification ranges of NILM/LSIL and HSIL+ mostly overlap, so the quantitative value (green line) of a specific sample cannot be identified. Is it HSIL+, or LSIL or NILM.

Similarly, another article 7 published in International Journal of Cancer in 2017 (impact factor: 7.316) studied the relationship between 5,319 non-16, 18 HPV viral loads and cervical lesions (only HSIL cases, no cancer cases). The study concluded that there was a statistical relationship between the quantitative mean (Mean) elevation of the 31, 35, 52, 58 subtypes in the HPVA 9 group and the risk of lesions, but at the same time, the data had a large dispersion (SD value). ), there was a high degree of overlap between the quantitative ranges of lesions and non-lesions.

Therefore, it is also clear at the end of the article that "Although an association between CIN2/3 and non-HPV16 viral load in the A9 group is recognized, our results do not justify changing the design of HPV testing currently in clinical use. ...because of the large overlap in the viral quantification range between women with and without CIN2/3."

The same phenomenon was also found in a quantitative study5 in the Fujian Maternal and Child Health Hospital affiliated to Fujian Medical University in 2018. All of these studies reflect the same picture: although there is a trend in the quantification of high-grade and low-grade lesions for HPV type 16 on average, the range of quantification for different lesions is highly overlapping, and for a specific sample Quantitative results of HSIL+ cannot be used to determine whether it is HSIL+, so it cannot really be used as a clinical diagnostic marker.

Based on the current clinical pathway, HPV 16 type is positive, direct referral to colposcopy, and HPV type 16 quantification cannot further risk stratification. Therefore, the correlation between HPV type 16 type and lesions has only scientific research value and does not have real clinical value. value.

2. "Preoperative HR-HPV viral load can be used as an indicator of residual lesions after HSIL+", clinical value?

In a follow-up study of 309 cases in Fujian Maternal and Child Health Hospital 8 (impact factor 3.738), the occurrence of CIN2+ within 6 months after operation was defined as surgical residual, and the occurrence of CIN2+ after ≥6 months was defined as recurrence. , preoperative HR-HPV quantification was closely related to surgical residual, but not to recurrence.

To confirm whether this research conclusion has real clinical value, it is necessary to compare it with the clinical pathway in the current guidelines.

According to the 2019 ASCCP guideline 9, for the management of HSIL after surgery, HPV primary screening or combined screening is uniformly adopted 6 months after surgery for follow-up. In a 2017 Lancet Oncology meta-analysis of 44,446 cases (97 studies) (impact factor 54.4)10, the sensitivity of postoperative HPV positive to CIN2+ reached 91.0%, much higher than 55.8% of positive surgical margins. Based on this, the guidelines believe that postoperative HPV detection is the most accurate indicator for predicting recurrence. Is preoperative HPV quantification or postoperative HPV qualitative detection more valuable?

We dig deeper into the content of this study and found that the study also compared the two indicators of postoperative HPV positive and positive surgical margins, both of which were significantly correlated with either residual or recurrence of HSIL after surgery. HPV quantification only has a certain predictive ability for residual lesions, so we can confirm that the efficacy of preoperative HPV quantification is not as good as the postoperative HPV detection recommended by current major guidelines, and it cannot bring greater clinical benefits. This predictive performance is also limited to scientific value.

In conclusion

Regarding HPV quantification in clinical practice, there are always a series of challenges:

From the biological mechanism, for high-grade lesions, the proportion of virus integration is high, and the virus replication is reduced; the high HPV load is mainly due to some low-grade lesions. In addition, the tissue heterogeneity of patients, and the multiple infections of different subtypes, also greatly increase the complexity of virus quantification.

From different clinical studies, the quantitative mean of HPV 16 type has a positive relationship with lesions of different grades, but the quantitative range (SD) is too wide and highly overlapped, making it difficult to truly guide clinical work. Quantification of non-A9 subtypes such as HPV 18, 45, 51, 56, 59 was not related to lesions. The quantification and lesions of other subtypes in the A9 group have inconsistent results from different studies, and the research evidence is not sufficient;

Some conclusions drawn from the current HPV quantitative research cannot prove that they have greater clinical benefits compared with the current clinical guidelines.

Reference

1.Woodman CB, Collins SI, Young LS. The natural history of cervical HPV infection: unresolved issues. Nat Rev Cancer. 2007 Jan;7(1):11-22. doi: 10.1038/nrc2050.

2.Schiffman M, Castle PE, Jeronimo J, Rodriguez AC, Wacholder S. Human papillomavirus and cervical cancer. Lancet. 2007 Sep 8;370(9590):890-907. doi: 10.1016/S0140-6736(07)61416-0.

3.McBride AA, Warburton A. The role of integration in oncogenic progression of HPV-associated cancers. PLoS Pathog. 2017 Apr 6;13(4):e1006211. doi: 10.1371/journal.ppat.1006211. eCollection 2017 Apr.

4.Zeni Wu, Wen Chen et al. Association between human papillomavirus (HPV) 16, HPV18, and other HR-HPV viral load and the histological classification of cervical lesions: Results from a large-scale cross-sectional study. J Med Virol. 2017 Mar;89(3):535-541. doi: 10.1002/jmv.24645. Epub 2016 Nov 10.

5.Dong B, Sun P, Ruan G, Huang W, Mao X, Kang Y, Pan D, Lin F. Type-specific high-risk human papillomavirus viral load as a viable triage indicator for high-grade squamous intraepithelial lesion: a nested case- control study. Cancer Manag Res. 2018 Oct 23;10:4839-4851. doi: 10.2147/CMAR.S179724. eCollection 2018.

6.Zhong F, Yu T, Ma X, Wang S, Cong Q, Tao X. Extensive HPV Genotyping Reveals High Association between Multiple Infections and Cervical Lesions in Chinese Women. Dis Markers. 2022 Jun 10;2022:8130373. doi: 10.1155/2022/8130373. eCollection 2022.

7.Fu Xi L, Schiffman M, et al. Type-dependent association between risk of cervical intraepithelial neoplasia and viral load of oncogenic human papillomavirus types other than types 16 and 18. Int J Cancer. 2017 Apr 15;140(8):1747-1756. doi: 10.1002/ijc.30594. Epub 2017 Jan 24.

8.Chen L, Dong B, Zhang Q, Mao X, Lin W, Ruan G, Kang Y, Sun P. HR?HPV viral load quality detection provide more accurate prediction for residual lesions after treatment: a prospective cohort study in patients with high?grade squamous lesions or worse. Med Oncol. 2020 Mar 30;37(5):37. doi: 10.1007/s12032-020-01363-z.

9.Perkins RB, et al. 2019 ASCCP Risk-Based Management Consensus Guidelines for Abnormal Cervical Cancer Screening Tests and Cancer Precursors. J Low Genit Tract Dis. 2020 Apr;24(2):102-131. doi: 10.1097/LGT.0000000000000525.

10.Arbyn M, Redman CWE, et al. Incomplete excision of cervical precancer as a predictor of treatment failure: a systematic review and meta-analysis. Lancet Oncol. 2017 Dec;18(12):1665-1679. doi: 10.1016/S1470-2045(17)30700-3. Epub 2017 Nov 7.

The Bioperfectus Technologies Human Papillomavirus (HPV) Genotyping Real Time PCR Kit is an in-vitro diagnostic (IVD) kit used for the detection of 21 different Human Papillomavirus (HPV) in patient specimens. The test specifically identifies 18 high-risk HPV types (16, 18, 31, 33, 35, 39, 45,51, 52, 53, 56, 58, 59, 66, 68, 26, 73, and 82) and three low-risk HPV types (6, 11, and 81).

The Bioperfectus Technologies Human Papillomavirus Real Time PCR Kit is intended for the in-vitro qualitative detection of nucleic acids of 18 HPV types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, 73, 53, 82, and 26) in cervical exfoliated cells, and genotyping for HPV16 and HPV18, but not for the other HPV types.