Initial infectionDelivery of infective virions to the host's
basal epithelial layer.
Viral persistenceMaintenance replication with concomitant
transformation of the infected cells.
Most cervical HPV infections are cleared or suppressed to undetectable levels
by cell-mediated immunity within 1-2 years of exposure.
Cervical intraepithelial neoplasia (CIN)MeSH
A malignancy arising in uterine cervical epithelium and confined
thereto, representing a continuum of histological changes
ranging from well-differentiated CIN 1 (formerly, mild dysplasia)
to severe dysplasia/carcinoma in situ, CIN 3. The lesion arises
at the squamocolumnar cell junction at the transformation zone
of the endocervical canal, with a variable tendency to develop
invasive epidermoid carcinoma, a tendency that is enhanced by
concomitant human papillomaviral infection.
(Segen, Dictionary of Modern Medicine, 1992)
Cervical intraepithelial neoplasia grade 1 (CIN1) MeSH
Also, uterine cervical dysplasia.
CIN1 is an insensitive hystopathological manifestation
of HPV infection. For any given type of carcinogenic HPV, diagnosing
CIN1 does not predict higher risk of progression to CIN3 than does
negative biopsy.
Patients confirmed with the
infection (by detection and genotyping of the virus DNA),
which had manifested in CIN1 (detected by Pap test and
other cytology-based methods) are usually
diagnosed only as having abnormalities and are
not targeted for treatment. Instead, they might be scheduled for a
follow-up examination without falsely informed
as being at risk of cancer.
Precancer
The time between infection and
appearance of the first microscopic evidence of precancer can be quite short, often
within 5 years. The average age of diagnosis of precancer varies from 25 to 35
years and depends on the average age at the first intercourse and on the
intensity of screening. In case of highly carcinogenic HPV16 precancer diagnosis
can reach as high as 40% of all detected infections.
Cervical intraepithelial neoplasia grade 2 (CIN2)
CIN2 is heterogeneous and sometimes is produced by
non-carcinogenic types of HPV. CIN2 should be treated, often
simple outpatient procedures (for example, cryotherapy) with subsequent follow-up
exams are sufficient.
Cervical intraepithelial neoplasia grade 3 (CIN3)MeSHCarcinoma in situ.
A lesion with cytological characteristics associated with invasive carcinoma
but the tumor cells are confined to the epithelium of origin, without invasion of the basement membrane.
In case of CIN3 undifferentiated cells with fixed genetic abnormalities
have replaced almost the full thickness of the cervical epithelium.
Without immediate treatment CIN3 progresses to invasive cancer.
Invasive cancer
Also called infiltrating cancer.
Cancer that has spread beyond the layer of tissue in which it developed and is growing
into surrounding, healthy tissues (Dictionary of cancer terms, NCI).
The peak risk of invasive cervical cancer occurs at 35-55 years of age.
The invasive cervical cancer is graded from grade I to IV.
Treatment of grade I requires surgery of different degrees of
invasiveness. In many cases patient's fertility can be
preserved. Higher grades might require the surgery to be
accompanied with radio- or chemotherapy.
