Cervical Cancer Flashcards
When is cervical cancer incidence at a peak?
younger women - peak in reproductive years
What type are 80% of cervical cancers?
Squamous cell carcinoma
What is the next most common type of cervical cancer?
Adenocarcinoma
What is the most common cause of cervical cancer?
Infection with human papilloma virus (HPV)
What cancers is HPV a/w/?
- cervical cancer
- anal
- vulval
- vaginal
- penis
- mouth & throat
Which of the over 100 strains of HPV are a/w/ cervical cancer?
16 & 18 (70% of cervical cancer)
How does HPV cause cancer?
P53 and pRb are tumour suppressor genes. They have a role in suppressing cancers from developing. HPV produces two proteins (E6 and E7) that inhibit these tumour suppressor genes. The E6 protein inhibits p53, and the E7 protein inhibits pRb. Therefore, HPV promotes the development of cancer by inhibiting tumour suppressor genes.
What are the signs factors for cervical cancer?
Increased risk of catching HPV:
* early sexual activity
* increased number of sexual partners
* not using condoms
Non-engagement with cervical screening
Other risk factors:
* smoking
* HIV (get yearly smears)
*. Combined contraceptive pill for more than 5 years
* increased number of full-term pregnancies
* family history
* exposure to diethylstilbestrol during fetal development (used to prevent miscarriages)
What are some of the presenting symptoms of cervical cancer?
- abnormal vaginal bleeding (IMB, PCB, PMB)
- vaginal discharge
- pelvic pain
- dyspareunia
What appearances may suggest cervical cancer?
- ulceration
- inflammation
- bleeding
- visible tumour
- refer for urgent colposcopy
What grading system is used for the level of dysplasia (premalignant change) in the cells of the cervix?
cervical intraepithelial neoplasia (CIN)
When is CIN diagnosed?
At colposcopy NOT with cervical screening
What abnormality is found during smear results?
Dyskaryosis
What are the different grades of CIN?
- CIN I = mild dysplasia, affecting 1/3 the thickness of epithelial layer, likely to return to normal w/o treatment
- CIN II = moderate dysplasia, affecting 2/3 the thickness of the epithelial layer, likely to progress to cancer if untreated
- CIN III = severe dysplasia, very likely to progress to cancer if untreated
What is CIN III aka?
Cervical carcinoma in situ
What way of transporting the cells of a smear test is used?
Liquid based cytology
How is a smear test examined?
Sample initially tested for HPV
If negative cells not examined
What is the routine timing of smear tests?
- every 3 years aged 25-29
- every 5 years aged 30-65
What are the exceptions to the routine screening program?
- Women with HIV are screened annually
- Women over 65 may request a smear if they have not had one since aged 50
- Women with previous CIN may require additional tests (e.g. test of cure after treatment)
- Certain groups of immunocompromised women may have additional screening (e.g. women on dialysis, cytotoxic drugs or undergoing an organ transplant)
- Pregnant women due a routine smear should wait until 12 weeks post-partum
What are the potential cytology results of a smear test?
- inadequate
- normal
- borderline changes
- low-grade dyskaryosis
- high-grade dyskaryosis (moderate)
- high-grade dyskaryosis (severe
- possible invasive squamous cell carcinoma
- possible glandular neoplasia
What infections may be identified on a smear test?
- bacterial vaginosis
- candidiasis
- trichomoniasis
How are cervical smear test results managed?
Inadequate sample – repeat the smear after at least three months
HPV negative – continue routine screening
HPV positive with normal cytology – repeat the HPV test after 12 months
HPV positive with abnormal cytology – refer for colposcopy
What stains can help differentiate areas during colposcopy?
- acetic acid
- iodine solution
What does acetic acid do during a colposcopy?
- causes abnormal cells to appear white = acetowhite
- cells with increased nuclear to cytoplasmic ratio such as CIN and cervical cancer cells
