Cervical Screening Symposium Flashcards
How common is HPV infection?
Human Papilloma Virus
- peak prevalence 15-25yrs
- prevalence declines with age
- 10% overall
- ~30% prevalence in young women
- lifetime risk of exposure up to 75% from serological studies
What is the basis of the HPV immunisation program?
After Sept 2014,
- 2 dose regime
- Helps protect them against cervical cancer, which is the most common cancer in women under 35 in the UK
What is cervical screening and what is the role?
- Method of detecting abnormal cells on the cervix
- [aka the smear test]
- Detect cervical dyskaryosis
- Reduce the risk of cervical cancer
- Detect CIN
- Prevent Cervical Cancer
- Smear is taken
- Smear taker enters request details onto SCCRS database (Scottish Cervical Call Recall System)
- Vials sent to lab receipt logged on SCCRS
- Patient details received from SCCRS, vials processed, slides stained and screened
- Cytology lab results put on SCCRS database
- SCCRS creates colposcopy referral
- Woman and GP receive results
When do women get the smear test?
- Women aged 25-64 years
- 3 yearly smears up to age 50
- 5 yearly from 50
- Liquid Based Cytology (LBC)
What is found via cervical cytology?
- Microscopic detection of abnormal squamous cells that are suggest underlying cervical intraepithelial neoplasia
- Identify women that have no abnormality and those requiring further investigation
What is normal cytology of the cervix?
- Squamous epithelial cells
- Other cells present (glandular etc)
- Benign nuclear features: small, uniform size and shape, fine regular chromatin
What is abnormal cytology of the cervix?
Abnormal = DYSKARYOSIS
- Abnormal cells may be few
- Nuclear features:
- increased size and nuclear/cytoplasmic ratio
- variation in size shape and outline
- coarse irregular chromatin
- nucleoli
- Graded low or high grade dyskaryosis - reflects degree of underlying CIN (Cervical Intraepithelial Neoplasia)
- Low grade (+ borderline nuclear abnormality) = 8%
- High grade = 1.4%
What does low grade dyskaryosis reflect?
- usually indicates HPV infection/CIN 1
What does the presence of Koilocytes reflect?
- Productive HPV infection
What does high grade dyskaryosis represent?
Underlying CIN3
What is cytology management when:
Normal?
Low grade dyskaryosis?
High grade dyskaryosis?
Normal: routine, 3 yearly
Low grade: repeat in 6 months
High grade: refer to colposcopy
What is colposcopy and what occurs at the first visit?
- Counselling
What is it?
- Magnification and light to see cervix
- Exclude obvious malignancy
- Use of acetic acid =/- Iodene:
- Identify limits of lesion
- Select biopsy site
- Define area to treat
What are the options for management post colposcopy?
- Punch biopsy to make a diagnosis
- Return for Treatment if CIN2/3
What occurs histologically in the transformation zone?
- Glandular lining cells of exposed endocervical epithelium transformed into squamous cells! (squamous metaplasia)
- Site of HPV infection
- Also the site of precancerous changes
What are the effects of HPV infection?
- Infects basal layer cells
- Utilises host for replication
- As host cell matures, different viral genes expressed
What is CIN??
Cervical intraepithelial neoplasia
- Abnormal proliferation of cells in squamous epithelium = cervical intraepithelial neoplasia (CIN)
- Precursor of invasive cancer
What dictates if CIN is 1, 2 or 3?
CIN1: Undiff cells only occupy lowest 1/3 of epith and surface cells can mature to big flat cells
CIN2: Undiff cells occupy 2/3 of thickness and only top layers show maturation to medium size cells
CIN3: Neoplastic cells or undifferentiated cells fill full thickness of epith here , no normal differentiated cells seen
Aetiology/RF for CIN?
- Almost all are associated with HPV particularly types 16 and 18
- Early age at first intercourse, multiple sexual partners, prolonged oral contraceptive use
- Cigarette smoking, STD’s, immunodeficiency
- Persistant infection
- Viral DNA > integration in host cell genome> overexpression of viral E6 and E7 proteins> deregulation of host cell cycle
What can happen to CIN?
- May regress or persist
- A minority (20-30%) of CIN 3 progress to invasive cancer over 10 - 20 years if untreated
What is squamous carcinoma in the cervix?
- Malignant change in squamous cells of transformation zone of cervix
- Abnormal cells invade the underlying tissues
What is the management of CIN?
- LLETZ
- Cold Coagulation
- Laser ablation
What is the follow up management after CIN treatment?
- Confirm treatment is effective
- Prevent invasive cancer: recurrent disease after 3-5 years, detect occasional cancer
- To reassure the woman
- Follow-up LBC at 6 months for cytology and high risk HPV: if both negative then return to recall, if either positive then return to colposcopy
What are the RF for cervical cancer?
- Peak age 45-55 years
- HPV related (16 & 18)
- Multiple partners
- Early age at first intercourse
- Older age of partner
- Cigarette smoking
Symptoms of cervical cancer?
- Abnormal vaginal bleeding
- Post coital bleeding
- Intermenstrual bleeding/PMB
- Discharge
- (Pain)
How is the diagnosis made for cervical cancer?
- Clinically
- Screen detected
- Biopsy
How is the staging of cervical cancer carried out?
- EUA (especially rectal) [examination under anaesthetic)
- PETR -CT
- MRI
What is involved in a radical histerectomy?
Removal of:
- Uterus, cervix, upper vagina
- Parametria
- Pelvic nodes
- Ovaries conserved
What are the management options for cervical cancer?
- Radiotherapy- External Beam x 20 fractions
- Chemotherapy- 5 cycles of cisplatin
- Caesium Insertion (24 hours)
- Stage 1a1:
- Excision biopsy (Cone/SWETZ)
- Stage 1b - 11a:
- Radical hysterectomy or
- chemo-radiotherapy
- Stage 11b - 1V:
- Chemo-Radiotherapy
What are the cure rates of cervical cancer?
1a: 99%
1b: 85%
11a: 75%
11b: 60%
111b: 33%
1V: 15%
