Cervical Cancer

Cervical cancer is a malignant tumor that develops from cells in the cervix, which is the lower part of the uterus connecting to the vagina. This type of cancer is largely preventable through vaccination and regular screening. When detected early, it is often highly treatable. Almost all cases (over 99%) are caused by persistent infection with high-risk strains of the Human Papillomavirus (HPV). HPV is a very common sexually transmitted infection; most people clear it naturally, but persistent infection with high-risk types (especially HPV 16 and 18) can lead to precancerous changes and eventually cancer.

1. Types:
   • Squamous Cell Carcinoma: Most common type (about 80-90%), arising from squamous cells lining the outer cervix (ectocervix).
   • Adenocarcinoma: Develops from glandular cells lining the cervical canal (endocervix). Becoming more common.
   • Adenosquamous Carcinoma / Mixed Carcinoma: Less common, features of both squamous and adenocarcinoma.
   • Other Rare Types: Small cell carcinoma, neuroendocrine tumors, sarcoma, lymphoma.
2. Symptoms (Often absent in early stages; appear as cancer advances):
   • Abnormal vaginal bleeding (after sex, between periods, after menopause)
   • Unusual vaginal discharge (may be watery, bloody, foul-smelling)
   • Pelvic pain or pain during sex (dyspareunia)
   • Bleeding or pain after a pelvic exam
   • Advanced disease: Leg swelling, back/pelvic pain, urinary/bowel problems, weight loss, fatigue.
3. Risk Factors:
   • Persistent high-risk HPV infection
   • Lack of HPV vaccination
   • Lack of regular cervical screening (Pap smear/HPV test)
   • Smoking (weakens cervical cells’ ability to fight HPV)
   • Long-term use of oral contraceptives (slight increased risk)
   • Having multiple sexual partners (increases HPV exposure risk)
   • Early age of first sexual intercourse
   • Weakened immune system (e.g., HIV/AIDS, immunosuppressive drugs)
   • Having other STIs (e.g., chlamydia, gonorrhea)
   • Socioeconomic factors limiting access to screening/healthcare
   • Family history (modest increased risk)
   • Diethylstilbestrol (DES) exposure in utero (rare)
4. Diagnosis (If screening abnormal or symptoms present):
   • Colposcopy: Magnified examination of the cervix using a special scope; often involves taking biopsies of abnormal areas.
   • Biopsy: Removal of tissue samples for microscopic examination (e.g., punch biopsy, endocervical curettage, cone biopsy/LEEP).
   • Cone Biopsy (Conization): Removes a cone-shaped piece of cervical tissue for diagnosis and sometimes treatment of precancer/early cancer (LEEP or cold knife cone).
   • Imaging (for staging): Pelvic exam under anesthesia, cystoscopy, proctoscopy, CT, MRI, PET-CT, Chest X-ray.
5. Precancerous Changes (Dysplasia/CIN/SIL):
   • HPV infection can cause abnormal cell growth on the cervix, known as cervical intraepithelial neoplasia (CIN) or squamous intraepithelial lesions (SIL).
   • These are graded as low-grade (mild changes, often clear on their own) or high-grade (moderate/severe changes, more likely to progress to cancer if untreated).
   • Regular screening detects these precancers so they can be treated before cancer develops.
6. Treatment (Depends heavily on stage, type, desire for fertility, overall health):
   • Precancer (CIN 2/3, HSIL): Outpatient procedures like LEEP, cryotherapy, laser ablation, or cold knife cone biopsy. Hysterectomy is rarely needed.
   • Early Stage (I, small IIA):
     • Fertility-Sparing: Cone biopsy (if very small IA1), Radical Trachelectomy (removes cervix/upper vagina, preserves uterus).
     • Surgery: Radical Hysterectomy (removes uterus, cervix, upper vagina, parametria, lymph nodes) +/- radiation/chemo based on pathology.
   • Locally Advanced (IB3, IIB-IVA):
     • Primary Chemoradiation: Combination of external beam radiation + brachytherapy (internal radiation) + concurrent chemotherapy (usually cisplatin). Standard treatment.
   • Metastatic/Recurrent (IVB):
     • Chemotherapy (often with platinum/paclitaxel +/- bevacizumab)
     • Immunotherapy (Pembrolizumab – for PD-L1 positive tumors, recurrent/metastatic disease)
     • Targeted Therapy (e.g., Tisotumab vedotin – for recurrent/metastatic disease)
     • Palliative Radiation
   • Palliative Care: Essential at all stages to manage symptoms and improve quality of life.
7. Screening & Early Detection (Crucial for Prevention):
   • Pap Smear (Pap Test): Collects cells from the cervix to look for precancerous changes or cancer cells.
   • HPV Test: Detects DNA/RNA of high-risk HPV types in cervical cells.
   • Co-testing: Pap smear and HPV test done together.
   • Screening Guidelines (vary slightly by country/org):
     • ACS/USPSTF: Start screening at age 25.
       • Ages 25-65: Primary HPV test every 5 years (preferred). OR Co-test every 5 years. OR Pap test every 3 years.
     • Stop screening after age 65 with adequate prior negative screening history and no high-grade precancer in the last 25 years.
     • After hysterectomy (with cervix removed) for non-cancer reasons, screening is usually not needed.
8. Prevention:
   • HPV Vaccination: The most effective prevention! Protects against HPV types 16 & 18 (causing ~70% of cervical cancers) and other high-risk/low-risk types, depending on the vaccine (Gardasil 9 protects against 9 types). Recommended for both girls and boys, ideally before sexual debut (ages 9-12), but catch-up available through age 26 (and sometimes older after discussion with a doctor).
   • Regular Cervical Screening (Pap/HPV tests): Detects precancer early for treatment.
   • Safe Sex Practices: Condoms reduce (but don’t eliminate) HPV transmission; limiting partners.
   • Smoking Cessation.
9. Prognosis:
   • Highly dependent on stage at diagnosis.
   • Early-stage (I): 5-year survival rates often exceed 90%.
   • Locally Advanced (II-III): 5-year survival rates range from approximately 40% to 65%.
   • Metastatic (IV): The 5-year survival rate is around 15-20%, though newer treatments (immunotherapy, targeted therapy) are improving outcomes for advanced disease.
   • Screening dramatically improves survival by enabling the detection and treatment of precancer and very early cancer.