Cervical Squamous Cell Carcinoma
~Introduction
Cervical squamous cell carcinoma (SCC) is the most common malignant tumor of the cervix, accounting for approximately 70–80% of all cervical cancers worldwide. It arises from the squamous epithelium of the ectocervix, usually at the transformation zone, where squamous epithelium meets glandular epithelium. Cervical cancer remains a major public health problem, especially in developing countries, despite being largely preventable through screening and vaccination.
Persistent infection with high-risk human papillomavirus (HPV) is the single most important etiological factor. Cervical SCC has a long precancerous phase, which allows early detection and treatment, significantly reducing mortality.
~Epidemiology
Cervical cancer is the fourth most common cancer in women worldwide
Higher incidence in low- and middle-income countries
Peak incidence: 45–55 years
Squamous cell carcinoma is more common than adenocarcinoma
Major cause of cancer-related death among women in developing nations
~Etiology and Risk Factors
Human Papillomavirus (HPV)
High-risk HPV types:
HPV 16 (most common)
HPV 18, 31, 33, 45
Persistent infection leads to malignant transformation
Other Risk Factors
Early age at first sexual intercourse
Multiple sexual partners
High parity
Poor genital hygiene
Smoking (carcinogenic effect on cervical epithelium)
Immunosuppression (e.g., HIV infection)
Long-term use of oral contraceptives
Low socioeconomic status
~Pathogenesis
Cervical squamous carcinoma develops through a well-defined sequence of precancerous lesions:
HPV infection
Cervical Intraepithelial Neoplasia (CIN)
Invasive carcinoma
Molecular Mechanism
HPV infects basal epithelial cells
Viral oncogenes E6 and E7:
E6 inactivates p53
E7 inactivates RB protein
Leads to:
Loss of cell cycle control
Genomic instability
Malignant transformation
~Precancerous Lesions: Cervical Intraepithelial Neoplasia (CIN)
| Grade | Description |
|---|---|
| CIN I | Mild dysplasia (lower 1/3 epithelium) |
| CIN II | Moderate dysplasia (lower 2/3 epithelium) |
| CIN III | Severe dysplasia to carcinoma in situ |
Untreated CIN III can progress to invasive carcinoma over several years.
~Gross Pathology
The tumor commonly arises in the transformation zone.
Gross Appearances
Exophytic (fungating) growth
Ulcerative lesion
Infiltrative mass
Advanced tumors may involve:
Vagina
Parametrium
Bladder
Rectum
~Histopathology
Microscopic Features
Invasive nests and cords of malignant squamous cells
Features include:
Pleomorphic cells
Hyperchromatic nuclei
Increased mitotic figures
Loss of normal stratification
Keratinization
Based on keratin formation, SCC is divided into:
1. Keratinizing Squamous Cell Carcinoma
Keratin pearls present
Intercellular bridges
Better differentiated
2. Non-keratinizing Squamous Cell Carcinoma
No keratin pearls
Sheets of malignant cells
Poorly differentiated
~Clinical Features
Early Stage
Often asymptomatic
Detected through screening (Pap smear)
Symptoms in Advanced Disease
Abnormal vaginal bleeding:
Postcoital
Intermenstrual
Postmenopausal
Foul-smelling vaginal discharge
Pelvic pain
Dyspareunia
Weight loss and anemia in late stages
~Spread of Disease
Local Spread
To vagina
Parametrium
Uterus
Lymphatic Spread
Pelvic lymph nodes:
Iliac
Obturator
Sacral nodes
Hematogenous Spread
Late occurrence
Lungs
Liver
Bone
~Staging (FIGO Staging – Simplified)
| Stage | Description |
|---|---|
| I | Confined to cervix |
| II | Beyond cervix but not pelvic wall |
| III | Pelvic wall or lower vagina involved |
| IV | Adjacent organs or distant metastasis |
Staging is clinical, not surgical.
~Diagnosis
Screening Methods
Pap smear (Papanicolaou test)
Liquid-based cytology
HPV DNA testing
Diagnostic Tests
Colposcopy
Cervical biopsy
Cone biopsy for early lesions
~Management
Early-Stage Disease
Conization
Radical hysterectomy
Fertility-sparing surgery in selected cases
Advanced Disease
Radiotherapy
Concurrent chemoradiation (cisplatin-based)
Metastatic Disease
Palliative chemotherapy
Supportive care
~Prognosis
Prognosis depends on:
Stage at diagnosis
Tumor size
Lymph node involvement
Depth of stromal invasion
Five-Year Survival Rate
Stage I: ~80–90%
Stage II: ~60%
Stage III: ~30%
Stage IV: <15%
~Prevention
Primary Prevention
HPV vaccination:
Bivalent
Quadrivalent
Nonavalent vaccines
Safe sexual practices
Secondary Prevention
Regular cervical screening
Early treatment of CIN
~Complications
Obstructive uropathy
Fistula formation (vesicovaginal, rectovaginal)
Severe anemia
Cachexia
Psychological distress
~Conclusion
Cervical squamous cell carcinoma is a preventable and treatable malignancy when detected early. Persistent infection with high-risk HPV plays a central role in its development. Effective screening programs, HPV vaccination, and timely treatment have significantly reduced disease burden in developed countries. Strengthening awareness, vaccination coverage, and screening services remains crucial to reducing morbidity and mortality, especially in developing regions.
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