Tutorial 16: Cervical Cancer Flashcards
What are some facts surrounding the history of cervical screening in New Zealand?
- National Cervical Screening Program was launched in New Zealand in 1990
- –> Since then the NCSP has resulted in a 40% reduction in the incidence of cervical cancer
- Breast Screen Aotearoa commenced their screening program in 1998
- In the first two years 1184 cancers have been detected through the program
- Testing for high risk HPV subtypes was introduced in New Zealand in October 2009
What are the WHO principles for developing a Screeing Prgram in terms of the condition?
- Should be an important health problem
- Should have a recognizable latent or early symptomatic stage
- The natural history of the disease, from latent phase to declared disease, should be adequately understood
What are the WHO principles for developing a Screening Program in terms of the test and treatment?
Test:
- There should be a suitable test or examination
- The test should be acceptable to the population
Treatment: There should be accepted treatment for patients with recognized disease
What are the WHO principles for developing a Screening Program in terms of the logistics of the program itself?
- Facilities for diagnosis and treatment should be available
- There should be an agreed policy on whom to treat as patients
- The cost of case finding (including diagnosis and treatment of patients diagnosed) should be economically balanced in relation to possible expenditure on medical care as a whole
- Case finding should be a continuing process and not a “once for all” activity
What is the epidemiology of cervical cancer worldwide?
- Worldwide, cervical cancer is the second-leading cause of cancer death in women
- Globally, each year around 500,000 women are diagnosed and nearly 300,000 die
What is the epidemiology of cervical cancer in New Zealand?
- In New Zealand, approximately 160 women develop cervical cancer each year and about 60 women die from it.
- Regular screening reduces the chances of getting cervical cancer. Without it, one in 40 women would develop cervical cancer.
- The death rate from cervical cancer for Maori women is four times as high as non-Maori women. The reason is not known however it is believed this is due to reduced compliance by Maori women with cervical screening.
- Cervical cancer has the youngest age of first diagnosis compared to other cancers. It often occurs in women in their 40s and 50s, when many are still raising children and contributing to their families’ livelihoods and security.
- Some groups of women have higher rates of cervical cancer. These include:
- Women over 40
- Māori and Pacific women
Which groups of woman in the NZ population have higher rates of cervical cancer?
- Woman >40yo
- Maori women
- Pacifica women
What facts surrounding the benefits and limitations of cervical and breast screening should you include when counselling woman on available screening?
Cervical screening is useful because cervical cancer is preceded by cellular changes which can be detected by taking a sample from the cervix.
- Treating the abnormalities leads to a reduction in cervical cancer.
With screening the chances of getting cervical cancer decreases from 1/90 women without screening –> to 1/570 women with screening.
Likewise the chances of dying from cervical cancer decreases to 1/1280 from 1/200 women without screening.
Who is included in the Cervical Screening Programme?
- Women 20-69y: Every 3 years
Which Woman are at increased risk for cervical cancer:
- 40+ women who’ve never had smear
- Those with no smear for 5 years
Women who don’t need smears are those who have:
- Had total hysterectomy with normal cervical cytology prev.
- Never had sexual intercourse
What is Cervical Intraepithelial Neoplasia?
- CIN = The presence of atypical cells in squamous epithelium of cervix.
- CIN is a Premalignant condition.
- Atypical cells show enlarged nuclei, increased nuclear/cytoplasmic ratio, increased mitoses.
- Severity of CIN graded according to depth of atypical cells
What are the three main features of atypical cells in CIN/the squamous epithelium of the cervix?
- Enlarged nuclei
- Increased nuclear:cytoplasmic ratio
- increased mitosis
What is the grading/severity used for CIN/cervical intrapeithelial neoplasia?
Severity of CIN graded by depth of atypical cells
CIN1 = atypical cells only in the lower 1/3 of epithelium
CIN2 = atypical cells in the lower 2/3 of epithelium
CIN3 = atypical cells throughout the full thickness of epithelium.
- CIN3 was previously know as CIS (carinoma in situ)
What are the two classification groups whicha re used when grading cervical intraepithelial neoplasia?
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Low Grade Squamous Intraepithelial lesions (LSIL)
- CIN1
- ASCUS (abnormal cells of undetermined significance)
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High Grade Squamous Intraepithelial Lesions (HSIL)
- CIN 2/3
What does ASCUS stand for?
ASCUS = Abnormal Squamous Cells of Undetermined Significance
What is the role of HPV (human papilloma virus) to cervical cancer?
HPV is sexually transmitted and cervical screening is only necessary for women who are sexually active.
- HPV is acquired soon after the initiation of sex
- But most HPV is cleared, especially in younger women – about 70% of young women clear HPV in 12 months.
- Types 6 and 11 cause genital warts
- Types 16 and 18 are responsible for around 70% of cervical cancers
Gardasil is a quadrivalent vaccine and is available on the NZ immunization schedule.
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Untreated, approximately 30% of women with HSIL (CIN2/3) would progress to invasive cervical cancer over 10 years.
- LSIL (CIN1) carries only a small risk of malignant progression. It may progress to CIN2/3 but it commonly resolves without treatment.
- LSIL in young women is usually watched initially – yearly smears for the first 3 years.
The presence and persistence of LSIL into the thirties suggests that the immune system has failed to clear the HPV and the follow up in this age group is different.
What particular subtypes of HPV are of importance regarding cervical cancer?
- 6 + 11 = genital warts
- 16 + 18 = 70% of cervical cancers
The high-risk types include:
- HPV 16, HPV 18,
- HPV 31, HPV 33, and HPV 45,
What is the Transformation Zone and what is its relevance to cervical cancer?
- Before puberty the:
- ectocervix is covered by stratified squamous epithelium
- endocervical canal and crypts are covered by columnar epithelium
- The original squamocolumnar junction is therefore near the external cervical os
- During puberty the tissues in the lower part of the cervical canal are everted and the glandular epithelium now comes to lie on the vaginal portion of the cervix
- This results in “Ectropion”: the protuberant endocervical mucosa surrounding the external os
- It has a granular, red and inflamed appearance on examination
What is the management of a patient with LSIL?
- 20-29yo: Repeat smear 1 year
- 20-69: 1 abnormal smear in last 5 years –> colposcopy
-
30+: HPV Test
- +ve HPV test = colposcopy
- -ve HPV test = Repeat in 1 year, then return to normal screening program
What type of language and specific points should be covered when explaining smears?
- Non discriminative, empathetic and Understanding
- Specific points to explain
- Abnormal cells do not mean cancer
- MUST ATTEND SPECIALIST APPOINTMENT DUE TO HIGH RISK