Cervical cancer

What it is

Cervical cancer is cancer that starts in the cervix, and about 95% of cases are linked to persistent high-risk HPV infection. The cervix is the lower part of the uterus that opens into the vagina. Worldwide, WHO estimated about 604,000 new cases and about 280,000 deaths in 2024, making it one of the most important preventable cancers in women.

Most cervical cancers develop slowly. Infection with high-risk human papillomavirus, especially when it persists for years, can cause precancerous changes in cervical cells that may later become invasive cancer if not found and treated. WHO notes that this process often takes 15 to 20 years in people with normal immune function, but it can progress faster, in about 5 to 10 years, in people with weakened immunity such as untreated HIV.

The two main histologic types are:

Type	Approximate share	Where it starts
Squamous cell carcinoma	About 70% to 80%	Flat cells on the outer cervix
Adenocarcinoma	About 20% to 25%	Glandular cells lining the cervical canal

Cervical cancer is largely preventable through HPV vaccination, screening, and treatment of precancer. This matters in India because access to screening and timely follow-up still varies by region, and many cases are diagnosed only after symptoms begin.

How it works

Cervical cancer usually begins with persistent infection by an oncogenic HPV type. HPV is a very common sexually transmitted infection, and most sexually active people are exposed at some point. In most people, the immune system clears the virus. Cancer risk rises when high-risk HPV infection does not clear and instead causes ongoing changes in cervical cells.

Over time, viral effects on cell-cycle control can lead to dysplasia, also called cervical intraepithelial neoplasia or squamous intraepithelial lesions. These precancerous changes are not the same as cancer, but some can progress if untreated. The sequence is often:

1. HPV infection
2. Persistent high-risk HPV infection
3. Precancerous cervical changes
4. Invasive cervical cancer

Risk is higher in people with HIV or other causes of immune suppression, smokers, and those with limited access to screening and treatment. WHO also lists other factors associated with progression, including coinfection with other sexually transmitted infections, higher parity, younger age at first pregnancy, and long-term hormonal contraceptive use. These factors do not cause cervical cancer by themselves, but they can affect risk.

Diagnosis / how it's measured

Early cervical cancer often causes no symptoms, which is why screening is important. Symptoms, when they occur, can include bleeding after sex, bleeding between periods, bleeding after menopause, unusual vaginal discharge, pelvic pain, or pain during intercourse. These symptoms are not specific to cancer, but they should be assessed.

Diagnosis and staging usually involve a stepwise approach:

Step	What it looks for
Cervical screening test	Detects HPV and or abnormal cervical cells before cancer develops
Colposcopy	Magnified examination of the cervix after an abnormal screening result
Biopsy	Confirms whether cancer or precancer is present
Imaging, if cancer is confirmed	Assesses local spread and distant disease

Screening methods vary by setting and guideline, but commonly include HPV testing, cytology (Pap test), or both. A positive screening test does not mean a person has cancer. It means further evaluation is needed.

Once cancer is diagnosed, staging describes how far it has spread. Treatment decisions depend on stage, tumour size, lymph node involvement, fertility goals, and overall health. In practice, clinicians may use pelvic examination, colposcopy findings, biopsy, and imaging such as MRI, CT, or PET-CT where available.

Evidence and uses

The strongest evidence in cervical cancer is for prevention and early detection. HPV vaccination reduces infection with cancer-causing HPV types and lowers the risk of cervical precancer. Screening detects precancer or early cancer before symptoms appear. WHO's elimination strategy uses the 90-70-90 targets: 90% of girls fully vaccinated by age 15, 70% of women screened by ages 35 and 45, and 90% of women with precancer or cancer treated appropriately.

Treatment depends on stage:

Situation	Common treatment approaches
Precancer	Ablation or excision, depending on lesion type and setting
Very early cancer	Surgery may be used, sometimes fertility-sparing in selected cases
Locally advanced cancer	Chemoradiation is often standard
Recurrent or metastatic cancer	Systemic therapy such as chemotherapy, targeted therapy, and in some cases immunotherapy

For invasive disease, outcomes are generally better when cancer is found early. Surgery may be enough for some early-stage cancers. More advanced disease often needs combined treatment, especially radiation with chemotherapy. Newer targeted and immune-based treatments help some patients, but they are not suitable for everyone and access can differ across centres.

In India, cervical cancer remains a major public health issue despite being preventable. National and state programmes increasingly support screening and HPV vaccination, but uptake, awareness, and follow-up remain uneven. For patients and families, the practical point is that abnormal bleeding or discharge should not be ignored, and screening is useful even when there are no symptoms.

When to see a clinician

See a clinician promptly if there is bleeding after sex, bleeding between periods, bleeding after menopause, persistent foul-smelling or watery discharge, or ongoing pelvic pain. These symptoms often have non-cancer causes, but they need evaluation.

Also seek care if a screening test is abnormal, even if you feel well. Many people delay colposcopy or biopsy because they have no symptoms, but this is exactly when precancer can often be treated most effectively.

People living with HIV, those with a weakened immune system, and those who have not had regular screening may need especially careful follow-up. If you are in India and unsure where to go, a gynecologist, gynecologic oncologist, or a hospital with colposcopy and pathology services is usually the right starting point.

Limitations and open questions

Although the main cause of cervical cancer is well established, not everyone with HPV develops cancer, and researchers are still studying why some infections persist while others clear. Immune factors, smoking, coinfections, and social determinants all appear to matter.

There are also real health-system limitations. Screening only works well when abnormal results are followed by colposcopy, biopsy, and treatment. In many low- and middle-income settings, including parts of India, loss to follow-up remains a major barrier.

Evidence for HPV vaccination and screening is strong, but the best way to deliver these services at scale can differ by region. Questions remain about how to expand coverage, reduce stigma, improve access for rural populations, and ensure timely treatment after an abnormal test. For individual patients, the key uncertainty is not whether prevention works, but whether care can be reached early enough.