CPC - neoplasia - lecture notes - julia

Question 1

what does a diagnosis of ASCUS mean?

Answer 1

• in response to a pap smear
• someplace in between normal and abnormal cells
• atypical squamous cells of unknown significance
• 20-30% of people get this diagnosis
• would do a biopsy to figure otu what to do from there

Question 2

what is the prevalence of HPV in the US? what is the incidence rate of new infections?

Answer 2

• 20 million currently infected
• 5.5 million infected each year

Question 3

how long do HPV-associated cancers take to develop? how do rates of cervical cancer amoung young women compare to other cancers?

Answer 3

• can take 10 to 20 years to develop
• cervical cancer affects younger women more frequently than most other types of cancer

Question 4

how many people die of cervical cancer annally worldwide? how many new cases are diagnosed? what age group is most likely to be affected?

Answer 4

• second most common cause of female cancer mortality worldwide
• approximately 510,000 new cases annually
• 288,000 deaths
• most cases between ages 30 and 50
• 15% of cases in women between 20 and 34

Question 5

describe the progression of cervical cancer

Answer 5

• starts as a benign noninvasive or squamous intraepithelial lesion (SIL) or CIN
• most low-grade epithelial lesions regress
• some remain unchagnged
• 10-15% progress to moderate or severe dysplasia - carcinoma in situ
• high grade CIN may develop into invasive cancer after years or decades

Question 6

which strains of HPV are most likely to cause invasive or malignant cervical cancers?

Answer 6

16, 18, and 45 are the most prevalent detected

on different slide says: 16,18, 31, 39, 45, 59

Question 7

what are the cervical cancer screening guidelines according to the american cancer society? (when to start, in what interval, when to stop?)

Answer 7

• start 3 years after onset of vaginal intercourse but no later than age 21
• test annually for women under 30
• every 2-3 years for women over 30 with 3 negative cytology tests
• liquid based cytology every 2-3 years for women over 30 with 3 negative cytology tests
• hpv testing every 3 years if HPV and cytology negative
• stop for women over 70 who have over 3 recent, negative cytology tests and no abnormal tests in 10 years

Question 8

how is a conventional pap smear collected? what does it look like? what are the disadvantages?

Answer 8

• specimen collected with brush - make smear on slide - put on fixative and send to lab
• problems:
• majority of cells not captured
• non-representative transfer of cells
• clumping and overlapping of cells
• obscuring material

Question 9

how is a thinprep pap test performed? what does it look like? what are the advantages of this test over a conventional pap smear?

Answer 9

• specimen also collected with brush - brush put in vial of methanol fixative - cells fixed instantaneously - sent off to lab - liquid evaporated and sample put on slide
• advantages:
• virtually all of sample collected
• randomized, represenational transfer of cells
• even distribution of cells
• minimizes obscuring material

Question 10

what are the different possible results of a pap smear? what do they mean? what do you do in response? (4)

Answer 10

1. normal
2. ascus - atypical cells of unclear significance
   - repeat pap and test for HPV DNA
3. LSIL = low grade squamous intra-epithelial lesion
   - colposcopy with biopsy
4. HSIL = high grade squamous intra-epithelial lesion
   - colposcopy with biopsy and treat

Question 11

what are the possible results of a cervical biopsy? (5) what do you do for each?

Answer 11

1. CIN I = mild dysplasia
   - usually spontaneously regresses
2. CIN II = moderate dysplasia
   - treat
3. CIN III = severe dysplasia
   - treat
4. carcinoma = in situ
   - treat
5. invasive cervical cancer
   - treat

Question 12

how does HPV cause cancer? (what do the viral proteins do that is carcinogenic?)

Answer 12

• protein E6 interacts with the host cell p53 and promotes its degradation via ubiquitin dependent pathway
• protein E7 complexes with Rb protein => inactivation of Rb

Question 13

what are the possible treatments for “high risk” hpv? (6)

Answer 13

• colposcopic biopsy - diagnosis for the state/grade of the HPV infection (high or low grade)
• LEEP = loop electrocautery excision procedure - cuts out infected site = most common procedure
• laser - burns off infected site
• cryosurgery - freezes off infected site
• general surgery = hysterectomy, vulvectomy (in rare cases)
• natural products - eg stress reduction, immune system boosters