# Persistently high prevalence of HPV16 and rising prevalence of non-16/18 HR-HPV genotypes in cervical precancer and cancer in Latvia in 2016-2024 shape the severity of cervical disease

## TL;DR

This study found that HPV16 remains the most common high-risk HPV in cervical cancer in Latvia, while other HPV types are increasing, suggesting a need for broader HPV testing.

## Contribution

The study reveals a shift in HR-HPV genotype prevalence and links disease severity to specific HPV types and viral load in Latvia.

## Key findings

- HPV16 was the most prevalent HR-HPV in cervical cancer and dysplasia, followed by HPV33, HPV39, and HPV18.
- HPV18 prevalence significantly decreased from 2016-2018 to 2022-2024, while other HR-HPV genotypes increased.
- Higher disease severity correlated with increased HR-HPV load and number of infecting genotypes.

## Abstract

Cervical cancer incidence and mortality in Latvia is one of the highest in Europe, but data on HR-HPV prevalence in cervical disease are lacking. We aimed to investigate HR-HPV prevalence in cervical squamous cell carcinoma (CSCC) and cervical dysplasia (CD), association with disease severity, and prevalence changes over time.

Cervical tissue samples from 145 patients were retrieved and used for HR-HPV genotyping using two commercially available PCR kits.

Only six CD samples were HR-HPV negative (6/66, 9.1%), while all CSCC were positive. Over 50% samples (75/139) harbored one, 33.8% two, 10.1% three, and 2.2% four HR-HPV genotypes. CSCC was more likely to harbor multiple HR-HPVs (p=0.0280). HPV16 remained most prevalent in CSCC and CD and was followed by HPV33 (32/139, 23.0%), HPV39 (13/139, 9.4%), and HPV18 (11/139, 7.9%). CSCC samples were more likely to have high HR-HPV loads (p=0.025). Disease severity expressed as CINI to CSCC grade 3, correlated with HR-HPVs detected (p=0.015, r=0.202) and HPV16 and HPV39 loads (p<0.001, r=0.354; p<0.001, r=0.307). prevalence decreased, insignificantly across the analyzed period, while HPV18 decreased significantly (2016-18: 17.4% vs. 2022-24: 2.2%; p=0.032). HPV66, 45, 39, 31, and 33 (2016-18: 13%; 2022-24:31.1%; p=0.045) increased.

HPV16 remained the most prevalent HR-HPV, while HPV18 decreased. Other HR-HPV genotypes (HPV 66/45/39/31/33) demonstrated an increase in prevalence. Cervical disease severity was linked to specific HR-HPV loads and the number infecting HR-HPVs. These findings highlight the need for extended HR-HPV genotyping with determination of viral load, and request more epidemiological studies analyzing historical and current samples.