ハイリスクHPVとローリスクHPVの相互作用は子宮頸部扁平上皮癌のリスクを下げる

ハイリスクHPVとローリスクHPVの同時感染が、子宮頸部扁平上皮癌への進行速度を抑制する

浸潤性癌でのみ有意な結果が得られており、上皮内癌への影響はなし

 

<label class="screenreader-text" for="MicrositeSearchTerm">北欧の大学病院などの共同研究</label>

<label class="screenreader-text" for="MicrositeSearchTerm">NCI: Journal of the National Cancer Institute, Volume 107, Issue 10, 1 October 2015</label>

Interactions Between High- and Low-Risk HPV Types Reduce the Risk of Squamous Cervical Cancer

Abstract

 

Background:

The clinical significance of co-infections with high-risk (HR) and low-risk (LR) human papillomavirus (HPV) in the etiology of cervical cancer is debated, as prospective evidence on this issue is limited. However, the question is of increasing relevance in relation to HPV-based cancer prevention.

Methods:

In two population-based nested case-control studies among women participating in cervical screening with baseline normal smears, we collected 4659 smears from women who later developed cancer in situ (CIS; n = 524) or squamous cervical cancer (SCC; n = 378) and individually matched control subjects who remained free of disease during study follow-up. The median follow-up until diagnosis was 6.4 to 7.8 years. All smears were tested for HPV. We used conditional logistic regression models with two-way interaction terms to estimate relative risks (RRs) for CIS and SCC, respectively. All statistical tests were two-sided.

Results:

Compared with women who were infected with HRHPV only, women who were also infected with LRHPV had a lower risk for SCC (RR = 0.2, 95% confidence interval [CI] = 0.04 to 0.99, P = .049). This interaction was not shown for CIS (RR = 1.1, 95% CI = 0.4 to 3.6). Women who were positive for both HRHPV and LRHPV had, on average, a 4.8 year longer time to diagnosis of SCC than women who were positive for HRHPV only (P = .006). Results were highly robust in sensitivity analyses.

Conclusion:

Co-infection with LRHPV is associated with a lower risk of future invasive disease and longer time to diagnosis than infection with HRHPV alone. We propose that co-infection with LRHPV interferes with the rate of progression to invasive cervical cancer.