cervical caner lab

Question 1

What are the risk factors for HPV infection?

Answer 1

• Risky sexual behaviour, many sexual partners, being younger than 25, starting to have sex at a young age (

Question 2

Role of HPV in cervical cancer

Answer 2

• Persistent infections increase the risk
• HPV divided into low (6 and 11) and high (16 and 18) oncogenic risk categories
• The duration of the infection is related to HPV type
  o The longer the infection, the higher oncogenic risk it will be

Question 3

How does it cause cervical cancer?

Answer 3

Integration of HPV into host cell DNA allows for an overexpression of E6 and E7 viral genes which encode proteins

• Both E6 and E7 enhance degradation of p53, therefore interrupting cell death pathways
• E7 binds to p21 and prevents its function as a cell cycle inhibitor
• E7 inactivates the retinoblastoma gene (Rb) blocking its proliferation-inhibitory function

Question 4

Screening programs and vaccination to prevent cervical cancer

Answer 4

• National cervical cancer screening program: to reduce morbidity and deaths from cervical cancer, in a cost-effective manner through an organised approach to cervical screening
  o Encourages women in the target population to have regular pap smear

Question 5

What is the pap smear test?

Answer 5

• ells from the transformation zone of the cervix are obtained via a spatula or brush
• Smeared onto slide, fixed and stained using Papanicolaou method

Question 6

HPV vaccine

Answer 6

• Available in Australia in 2006
• Designed to reduce incidence of cervical cancer caused by HPV types 16 and 18 and condylomas caused by HPV 6 and 11.
• Gardasil—quadrivalent vaccine currently used for the Australian national HPV vaccination program

Question 7

Clinical features of cervical cancer

Answer 7

• Mostly asymptomatic, abnormal pap smear, abnormal bleeding (post-coital or intermenstrual), pain, haematuria and weight loss

Question 8

Macroscopic appearance

Answer 8

• Early lesions visible only on colposcopy
• Focal induration, ulceration, elevated granular areas that bleeds when touched
• Advanced lesions
  o Endophytic – ulcertated
  o Exophytic – polypoid or papillary tumour mass
• Squamous cell carcinoma 80% of all cases
  o Precursor CIN 3, characterised by nests and infiltrative tongues of malignant squamous cells with large, irregular and hyperchromatic nuclei invading beyond the epithelium into the cervical stroma

Question 9

treatment of cervical cancer

Answer 9

• Depends on the clinical stage (see below)
• Early invasive carcinoma cone biopsy only
• Invasive lesions hysterectomy and lymph node dissection

Advanced lesions surgery and/or adjunct radiotherapy and chemotherapy

Question 10

What is the significance of an aceto-white area in cervical cancer testing?

Answer 10

It is a hall mark of colposcopic diagnosis of CIN

Question 11

What is an LLETZ?

Answer 11

Large loop excision of the transformation zone

Question 12

What are histological changes of SCC?

Answer 12

Nests of tumour cells, keratinous pearls and reduced stroma, with lymphocytes.
There can also be a poor differentiation with a high degree of pleomorphism and mitotic activity
Keratinizing squamous cell carcinomas have polygonal cells with bizarre shapes

Question 13

What type of cell lines the ectocervical mucosa?

Answer 13

Stratified squamous epithelium

Question 14

What type of cell lines the endocervical mucosa?

Answer 14

Simple columnar epithelium. This is mucous secreting

Question 15

Is the endocervix or the ectocervix closer to the vaginal opening?

Answer 15

Ectocervix