Jabbing back: HPV vaccination turns the tables on cervical threats

As of 2020, cervical cancer ranks fourth place in the topmost common cancers in people with a female reproductive system, with approximately 604,000 new cases and 342,000 deaths¹

In the UK, specifically, around 850 people die per year from cervical cancer, equating to more than two people a day.² While cervical cancer is seen as a silent threat to women’s health, it is preventable and, if caught early enough at diagnosis, treatable. 

In this article, we will take a journey through the world of vaccination against Human Papillomavirus (HPV) – our ally in the fight to eliminate cervical cancer. 

Understanding cervical cancer

In order to understand the importance of HPV vaccination, we need to understand what cervical cancer is and how HPV plays a role in its development.

The cervix is a narrow channel found between the lower part of the uterus (womb) and the vagina (birth canal) and is made up of two parts: the ectocervix (the outer part that can be seen in gynaecological exams) and the endocervix (the inner part of the cervix, forming the canal that connects the vagina to the uterus).³

Cervical cancer often develops in these two parts of the cervix. It is a slow-growing tumour, often developing over a period of years. During this development, the cervix will go through various changes, known as dysplasia – abnormal cells grow in the cervical tissue, and if not removed or destroyed, may develop into cancer cells which can start to grow and spread in the cervix and surrounding areas of the uterus.³

Squamous cell carcinoma and adenocarcinoma make up the main types of cervical cancer. Four out of five cervical cancers diagnosed are squamous cell carcinomas, developing in the ectocervix. However, some cervical cancers can be a mixture of both squamous cell carcinoma and adenocarcinoma, known as mixed carcinoma. It’s very rare for cancer to develop in other cell types present in the cervix.³

The role of HPV in cervical cancer

So, now that we understand what cervical cancer actually is, it’s time to look at the role of HPV.

You might be wondering how a virus plays into the development of cancer, but it’s important to note that persistent infection with high-risk types of HPV causes nearly every case of cervical cancer. Two of the highest risk HPV types (HPV-16 and HPV-18) are responsible for 70% of cervical cancers diagnosed globally.⁴

People who are sexually active may become infected with HPV at some point during their life. Normally, the immune system will manage the virus and will clear the infection in a short period of time; however, some HPV infections can last for years, increasing the likelihood of damage (and changes) to cells, precancerous lesions, and, if not treated promptly, development into cervical cancer.⁴

Why is HPV vaccination important?

The HPV vaccine has become a primary way to protect people against high-risk types of HPV that can cause cancer, including cervical cancer.

The vaccine contains a simulation of the HPV virus (not a real live virus)⁵ and triggers the body to think that it has encountered a real HPV virus, prompting an immune response and, subsequently, antibody production.⁶

The immune system acts like a memory card, remembering pathogens. If exposed again, it fights off the virus more efficiently, reducing symptoms and recovery time. The quicker response to the HPV pathogen (as a result of the vaccine) in turn lowers the risk of cervical cancer.⁶

It is important to note that the vaccine will not completely remove the risk of developing cervical cancer.⁶

In the UK, the vaccination is offered to children aged 11–13, adults up to the age of 25, men who have sex with other men, and some transgender adults.⁶

Since the UK’s introduction of the vaccine in September 2008, there have been impressive results.  A UK study conducted in 2021 found that cases of cervical cancer in women in their 20s had decreased by almost 90% in England, after receiving the vaccine at 12–13 years old.⁶

Future outlook

Cervical cancer could soon become a thing of the past. In November 2023, NHS England pledged to eliminate cervical cancer by 2040, potentially saving lives across the country.⁷  This goal of elimination has also been put into motion by the WHO, where they have suggested an even earlier target of 2030 for all countries to aim for the eradication of cervical cancer. To achieve this they have drawn up the 90–70–90 targets, which rely on three key aspects:⁸ 

•     Vaccinate 90% of girls with the HPV vaccine by 15 years of age
•     Screen 70% of women using a high-performance test by the age of 35, and again by the age of 45
•     Treat 90% of women with pre-cancer and manage 90% of women with invasive cancer

To achieve this, the NHS and health authorities around the globe will need to ensure that vaccination rates remain stable and encourage attendance to cervical screening appointments.⁷

Recently, there have been advances in healthcare professionals' approaches to screening cells for cervical cancer, with more high-performance screening tests being introduced to healthcare facilities around the world. 

In 2022, University Hospital Monklands in Airdrie, Scotland became a trailblazer in the UK and one of the global early adopters of a pioneering cervical screening technology incorporating AI.⁹

This innovative technology utilises the Genius™ Digital Diagnostics System, a digital cytology system owned by the women's health company Hologic. The system generates digital images of cervical smear slides obtained from patient samples that tested positive for HPV.⁹ 

Using a sophisticated algorithm, AI compares these samples against a library of the most diagnostically relevant cells. This process enables medical staff to identify abnormalities promptly and accurately, providing a higher level of precision compared with previous methods due to a reduction in the number of cells requiring analysis.⁹

The pilot at University Hospital Monklands has already demonstrated a 25% increase in slide assessment capacity and improved analysis turnaround times. Consequently, medical staff have gained additional time for training and are able to focus on more challenging cases of cervical cancer diagnosis.⁹

These outcomes highlight the significant impact of AI in improving outcomes for women with abnormal cells or those who have progressed to develop cervical cancer.

Summary

It is abundantly clear that we as a population harness the power to shape a future for ourselves where cervical cancer is no longer a silent threat. We should continue to commit to our understanding of cervical cancer and to our advocacy for HPV vaccination – a highly effective tool for reducing the incidence of this disease. It is one of many keys that unlocks a world free from the looming shadows of a cervical cancer diagnosis, but an important one.

References

1. World Health Organisation. Cervical cancer. 17 November 2023. Available at: https://www.who.int/news-room/fact-sheets/detail/cervical-cancer. Last accessed: January 2024
2. Cancer research UK. Cervical cancer statistics. Available at: https://www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/cervical-cancer#heading-Two. Last accessed: January 2024.
3. National Cancer Institute. What is cervical cancer. Available at: https://www.cancer.gov/types/cervical. Last accessed: January 2024.
4. National Cancer Institute. Cervical cancer causes, risk factors and prevention. Available at: https://www.cancer.gov/types/cervical/causes-risk-prevention. Last accessed: January 2024.
5. Cleveland Clinic. HPV vaccine. Available at: https://my.clevelandclinic.org/health/treatments/21613-hpv-vaccine. Last accessed: January 2024.
6. Cancer research UK. The HPV vaccine. Available at: https://www.cancerresearchuk.org/about-cancer/causes-of-cancer/infections-eg-hpv-and-cancer/the-hpv-vaccine. Last accessed: January 2024.
7. NHS England. NHS sets ambition to eliminate cervical cancer by 2040. 15 November 2023. Available at: https://www.england.nhs.uk/2023/11/nhs-sets-ambition-to-eliminate-cervical-cancer-by-2040/. Last accessed: January 2024.
8. WHO. Cervical cancer elimination initiative. Available at: https://www.who.int/initiatives/cervical-cancer-elimination-initiative. Last accessed: January 2024.
9. BBC News. New tech improves cervical cancer screening. Available at: https://www.bbc.co.uk/news/uk-scotland-glasgow-west-60648553. Last accessed: January 2024.