What are the prevention, diagnosis, and treatment options for cervical cancer?

Cervical Cancer: Prevention, Diagnosis, and Treatment

HPV vaccination and regular screening are the cornerstones of cervical cancer prevention, with HPV DNA testing providing superior protection compared to traditional cytology-based screening. 1

Epidemiology and Risk Factors

• Cervical cancer is the fourth most common female cancer worldwide, causing approximately 265,700 deaths annually, with nearly 90% occurring in developing countries 1, 2
• HPV is detected in 99% of cervical tumors, with HPV 16 and 18 accounting for approximately 70% of cases 1, 3
• HPV-16 is the most carcinogenic type (55-60% of cases), followed by HPV-18 (10-15% of cases), with HPV-18 more common in adenocarcinomas than squamous cell carcinomas 3
• Risk factors for progression from HPV infection to cancer include persistent HPV infection, older age, long-term oral contraceptive use, high parity, smoking, HIV infection, and early age at first sexual intercourse 3

Prevention

Primary Prevention: HPV Vaccination

• Three HPV vaccines are available: bivalent (2vHPV), quadrivalent (4vHPV), and nine-valent (9vHPV) 1
• All vaccines protect against HPV 16 and 18; 4vHPV adds protection against HPV 6 and 11 (causing genital warts); 9vHPV covers five additional oncogenic types (31,33,45,52, and 58) 1
• Vaccination is most effective when administered before exposure to HPV (before sexual activity begins) 4, 5
• Population-level benefits appear as early as 3 years after introduction of vaccination programs, including decreased incidence of high-grade cervical abnormalities 1
• Vaccination is expected to prevent more than 70% of cervical cancers 1

Secondary Prevention: Screening

• Cervical cancer screening should begin at age 21 regardless of sexual history or other risk factors 1
• For women 21-29 years, screening with cytology (Pap test) alone every 3 years is recommended 1
• HPV testing should not be used for screening women under 30 years 1
• HPV-based screening provides 60-70% greater protection against invasive cervical cancer compared to cytology-based screening 1
• HPV-based screening with triage at prolonged intervals is recommended starting at age 30 1
• Annual screening is not recommended for women at any age by any screening method 1

Diagnosis and Staging

• Diagnosis requires examination under anesthesia and imaging studies 1
• Computed tomography (CT) can detect pathological lymph nodes 1
• Magnetic resonance imaging (MRI) can determine tumor size, stromal penetration, parametrial involvement, vaginal extension, and corpus extension with high accuracy 1
• Positron emission tomography (PET) can accurately delineate disease extent, particularly in lymph nodes and distant sites 1
• In early-stage disease, PET/CT has 53-73% sensitivity and 90-97% specificity for lymph node involvement 1
• In advanced stages, sensitivity for para-aortic node involvement increases to 75% with 95% specificity 1

Management of Precancerous Lesions

• CIN-1 (low-grade lesions) can be managed with follow-up without treatment, including repeat Pap tests at 6 and 12 months or HPV DNA testing at 12 months 6
• For CIN-1 requiring treatment, options include cryotherapy, laser ablation, loop electrosurgical excision procedure (LEEP), electrofulguration, and cold coagulation 6
• For CIN-2,3 (high-grade lesions) with satisfactory colposcopy, both excision and ablation are acceptable, with excisional methods preferred for recurrent cases 6
• Diagnostic excisional procedures are recommended for CIN-2,3 with unsatisfactory colposcopy 6
• Women of reproductive age should be counseled about increased risks of preterm birth before undergoing LEEP 6

Treatment of Invasive Cervical Cancer

Early Stage Disease (IA1-IIA1)

• Stage IA1 without lymphovascular space invasion (LVSI) can be managed with conization without lymphadenectomy to preserve fertility 1
• Stage IA2 without LVSI can be treated with conization or extrafascial hysterectomy; with LVSI, pelvic lymphadenectomy is indicated 1
• Stages IB1-IIA1 can be treated with either radical surgery including pelvic lymphadenectomy or radiotherapy, with similar 5-year survival rates 1

Locally Advanced Disease

• Treatment consists of radiotherapy or a combination of radiotherapy and chemotherapy 1
• Definitive radiation therapy should include pelvic external beam radiation with high-energy photons and intracavitary brachytherapy 1
• Radiation must be administered at high doses (>80-90 Gy) in a short time (<55 days) 1

Special Considerations

• Fertility preservation options exist for early-stage disease 1
• Excisional treatments have been associated with a 70% increase in risk for subsequent preterm delivery 6
• CIN-2 may be followed without treatment in young women who desire fertility and are reliable about follow-up 6
• Hysterectomy should be avoided as primary treatment for CIN-1 or CIN-2,3 6

Future Perspectives

• New treatment approaches include immunotherapies, targeted therapies, combination therapies, and genetic treatment approaches 2
• Artificial intelligence shows promise in cervical cancer screening by integrating image recognition with big data technology 7
• Cervical cancer could potentially be the first cancer eliminated through comprehensive prevention and control strategies 7