13.3 Cervix Flashcards
HPV vaccine
- what does it cover/not cover
- how long does vaccine last?
quadrivalent vaccine (6,11,16,18)
- 6,11 (condylomas–genital warts)
- 16,18 (most high risk for cervical cancer)
- note: does not cover other HPVs (eg 31,33)
- must get vaccine every 5 years.
Cervical carcinoma
- classic population
- key risk factor
- secondary risk factors (2)
- middle aged women (40-50), infected by HPV in 20s. (takes 25-30 years to develop carcinoma)
- high risk HPV infection
1. smoking
2. immunodeficiency (remember, immune system removes acute HPV 90% of time)
Cervical carcinoma
-progression of disease and late complications, classic
- More local than distant effects. HPV tumors typically grow locally and don’t metastasize until very late.
- invasion through anterior uterine wall into the bladder, blocking ureters. Hydronephrosis with postrenal failure–common cause of death in advanced cervical carcinoma.
Cervical intraepithelial neoplasia (CIN)
- how is severity classified?
- what are the grades, and what the % of reversability?
Divided into grades based on extent of epithelial involvement by immature dysplastic cells.
CIN I:
CIN II:
CIN III:
CIS: entire thickness–cannot reverse.
CIS becomes SCC
What’s general difference between dysplasia and CIS?
dysplasia progresses into CIS.
dysplasia is typically reversible, while CIS is not.
(eg cervical carcinoma)
Cervical intraepithelial neoplasia (CIN)
-histology characterized by what (4)
persisitent HPV infection. In cervical epithelium:
- ‘raisin’ koilocytic change
- disordered cellular maturation
- nuclear atypia
- increased mitotic activity
Cervical carcinoma
-clinical presentation (2)
- vaginal bleeding (esp postcoital)
- cevical discharge
Pap smear:
-on histology, how to tell if cells are dysplastic?
-immature dysplastic cells are dark blue with high cytoplasmic ratios.
high risk HPV
-mech of genesis of cancer
-HPV virus produces E6 and E7
E6: increased destruction of p53 (traffic cop: stops at G1 and checks DNA damage. If damage, releases BAX, which destroys Bcl2, which results in Cyt C leakage and apoptosis)
E7: increased destruction of Rb (holds key of E2F–must be phosphorylated to release key of E2F (TF) for G1–>S)
Female pt is infected sexually by HPV
-what typically happens next w/o tx?
- 90% of time, infection is eradicated by acute inflammation
- persistent infection leads to increased risk for cervical dysplasia (CIN)
- HPV usu infects transformation zone of cervix
Pap smear:
-important limitations to this test (2)
- inadequate sampling of transformation zone (false negatives)
- limited efficacy in screening for adenocarcinoma
Why do women who took the HPV vaccine still need to get regular Pap smears?
HPV vaccine only covers common HPVs 6,11,16,18
Pap smears:
- how does it take for CIN to become carcinoma?
- start what age, how often to perform?
- what happens in pap smear
- goal: catch CIN before it develops into CIS and carcinoma.
- takes 10-20 years for CIN to become carcinoma
Pap smears:start age 21, perform every 3 years.
-scrape cells from transformation zone with brush. look for dysplasia and grade it.
Cervix
-divided into what anatomical parts?
- exocervix–squamous, nonkeratinizing
- endocervix–columnar
junction is Transformation zone
You do Pap smear and see lots of dark blue cells in the squamous epithelium.
-Do what next
after you suspect dysplasia:
- Confirmatory colposcopy
- visualization of cervix with magnifying glass - biopsy
