Cancer Screening Flashcards
What is the typical regimen for cervical cancer screening?
A Pap smear is offered to all women between the ages of 25 and 64 yo. Smear frequency depends on age:
- 25-49: 3-yearly screening
- 50-64: 5-yearly screening
- cervical screening cannot be offered to women over 64 yo (unlike breast screening, where patients can self-refer once past screening age)
https: //www.passmedicine.com/review/textbook.php?s=Papanicolaou
What special situations should be considered for cervical screening? (3)
- Cervical screening in pregnancy is typically delayed until 3 months post-partum UNLESS missed screening or previous abnormal smears
- Women who have never been sexually active have very low risk of developing cervical cancer and therefore may wish to opt-out of screening
- Women who have had a total hysterectomy including removal of the cervix no longer need cervical screening
https://www.passmedicine.com/review/textbook.php?s=Papanicolaou
What is the main aim of cervical screening?
To detect pre-malignant cells rather than to detect cancer (primary prevention)
What is the difference between a traditional Pap test and liquid-based cytology (LBC)?
Pap smears involve smearing sample cells onto a slide for microscopy, while LBC involves rinsing the sample into a preservative fluid or simply removing the brush head into the sample bottle with preservative fluid
What are the advantages of LBC over Pap? (2)
- Reduced rate of inadequate smears
- Increased sensitivity and specificity
**there is currently a move away from Pap toward LBC
When is the recommended time to take a cervical smear?
Despite limited evidence to support this, the NHS recommends taking a smear around mid-cycle
How is HPV testing incorporated into cervical screening?
The NHS has moved to an “HPV first” system ie a sample is tested for high-risk HPV first and then IF POSITIVE, cytological examination is performed
Furthermore, the introduction of HPV testing allows patients with mild dyskaryosis to be further risk-stratified, i.e. as HPV is such a strong risk factor patients who were HPV negative could be treated as having normal results.
https: //www.nhs.uk/conditions/cervical-screening/
https: //www.passmedicine.com/review/textbook.php?s=Papanicolaou#
What is the protocol for a smear that tests negative for hrHPV?
Return to normal recall (3 or 5 years depending on age) UNLESS:
- test of cure (TOC) pathway ie individuals who have been treated for CIN1, CIN2, or CIN3 (should be invited for follow-up in 6 mo)
- untreated CIN1 pathway
- follow-up for incompletely excised cervical glandular intraepithelial neoplasia, stratified mucin producing intraepithelial lesion, or cervical cancer
- follow-up for borderline changes in endocervical cells
https://www.passmedicine.com/review/textbook.php?s=Papanicolaou#
What is the protocol for a smear that tests positive for hrHPV?
Samples are examined cytologically and management is based on whether or not cytology is normal
What is the protocol for a hrHPV (+) smear with abnormal cytology?
Colposcopy
What cytological changes are considered abnormal on colposcopy? (6)
- Borderline changes in the squamous or endocervical cells
- Low-grade dyskaryosis
- High-grade dyskaryosis (moderate)
- High-grade dyskaryosis (severe)
- Invasive squamous cell carcinoma
- Glandular neoplasia
What is the protocol for hrHPV (+) smear with NORMAL cytology?
Repeat test in 12 months
- if repeat test is hrHPV (-), return to normal recall
- if repeat test is still positive, repeat cytology; if cytology normal, repeat in 12 months
> if hrHPV (-) at 24 mo, return to normal recall
> if hrHPV (+) at 24 mo, colposcopy
What is the protocol for a smear sample that is “inadequate?”
Repeat sample within 3 months; if two consecutive inadequate samples, colposcopy
What is the first step in the follow-up of patients who have previously had CIN?
Invitation for test of cure (TOC) repeat cervical sample 6 months after treatment
What are the high risk strains of HPV (hrHPV) associated with cervical cancer? (2)
Strains 16 and 18 (and 33)
**strains 6 and 11 are associated with genital warts
Aside from hrHPV infection, what other risk factors are associated with cervical cancer? (6)
- Smoking
- COCP
- High parity
- Early intercourse, multiple sexual partners
- HIV
- Low socioeconomic status
Under what circumstances would a woman over the age of 64 be invited for a cervical smear?
If one of her last 3 tests was abnormal
https://www.nhs.uk/conditions/cervical-screening/when-youll-be-invited/
What test is used first line for bowel cancer screening?
FIT kit (fecal immunochemical test)
https://www.nhs.uk/conditions/bowel-cancer-screening/
When is bowel cancer screening offered?
Offered to patients aged 56-74 every 2 years
Patients 75 yo and older may request a home test kit every 2 years
*one-off bowel-scope screening is no longer offered at age 55 yo (colonoscopy)
Why is FIT preferred to FOBT for bowel screening?
FIT (fecal immunochemical test) screening is more specific to human blood and DOES NOT require restricted diet before taking the stool sample; FIT is also more specific to blood from the lower GIT
VS
FOBT may register animal blood (eg from red meat) as a positive test result; also false positives from vitamin C, aspirin, ibuprofen, broccoli, and turnips consumed up to 3 days before the test; FOBT is sensitive to blood from the upper GIT and is therefore less specific for bowel cancer
