Cervical cancer is the second most common cancer in women after Breast Cancer
It has been estimated that 500,000 cases are diagnosed annually in the world and 80% of these are in the developing countries.
Cause of Cervical Cancer
- The relationship between cervical cancer and sexual activity was first noted more that 150 years ago.
- Since then it has been assumed that sexually transmitted infection may be the underlying mechanism.
- Many sexually transmitted infections have been suggested and linked to the disease. Perhaps the greatest difficulty has been that those who have acquired one sexually transmitted disease have been at risk of acquiring others.
- A variety of possible organisms have been implicated including Chlamydia trachomatis and herpes simplex.
- Only in the last twenty years have studies of cervical cancer demonstrated that at least 99.8% are associated with the human papillomavirus (HPV). There are many ‘types’ of HPV with HPV type 16 accounting for 50%, HPV 18 for 12%, HPV 45 for 8% and HPV 31 for 5%.
- Human papillomavirus (HPV) infection is a
necessary factor in the development of nearly
all cases of cervical cancer.9601,
9901 The virus cancer link works by
triggering alterations in the cells of the
cervix, leading to the development of cervical
intraepithelial neoplasia which may in turn lead
to cancer. Women who have many sexual partners
(or who have sex with men or women who had many
partners) have a greater risk.
An effective HPV vaccine against
the two most common cancer-causing strains of
HPV has recently been licensed in the U.S. .
These two HPV strains together are responsible
for approximately 70%0601
of all cervical cancers. Experts recommend that
women combine the benefits of both programs by
seeking regular Pap smear screening, even after
vaccination.
Acquisition of HPV does not necessarily mean that pre-malignancy or malignancy of the cervix will occur. Experts believe that 20% of women will acquire HPV at some time in their lives but the virus is removed from the body in the majority. A number of factors determine whether the HPV will not be eliminated and whether pre-malignancy and then malignancy will occur. Some people have a genetic predisposition to malignancy. Smoking reduces the efficiency of the immune system increasing the risks. The socially disadvantaged are most at risk of cervical cancer. The condom method of contraception provides protection against cervical cancer. Women who have used oral contraception are twice as likely to have high grade pre-malignant conditions of the cervix compared to those who never used it probably because they have been less likely to have used a barrier method of contraception.
More than 250 types of HPV are acknowledged
to exist (some sources indicate more than 200
subtypes). Of these, 15 are classified as
high-risk types (16, 18, 31, 33, 35, 39, 45, 51,
52, 56, 58, 59, 68, 73, and 82), 3 as probable
high-risk (26, 53, and 66), and 12 as low-risk
(6, 11, 40, 42, 43, 44, 54, 61, 70, 72, 81, and
CP6108),0301
but even those may cause cancer. Types 16 and 18
are generally acknowledged to cause about 70% of
cervical cancer cases. Together with type 31,
they are the prime risk factors for cervical
cancer.9902
The medically accepted paradigm, officially
endorsed by the American Cancer Society and
other organizations, is that a patient must have
been infected with HPV to develop cervical
cancer, and is hence viewed as a
sexually transmitted disease, but not all
women infected with HPV develop cervical cancer.0602
Despite the development of an HPV vaccine,
some researchers argue that routine neonatal
male
circumcision is an acceptable way to lower
the risk of cervical cancer in their future
female sexual partners. Others maintain that the
benefits do not outweigh the risks and/or
consider the removal of healthy genital tissue
from infants to be unethical as it cannot be
reasonably assumed that a male would choose to
be circumcised. There has not been any
definitive evidence to support the claim that
male circumcision prevents cervical cancer,
although some researchers say there is
compelling epidemiological evidence that men who
have been circumcised are less likely to be
infected with HPV.
However, in men with low-risk sexual behaviour
and monogamous female partners, circumcision
makes no difference to the risk of cervical
cancer.
Related Medical Abstracts - Click on the paper title:-
Signs and
symptoms of Cervical Cancer
The early stages of cervical cancer may
be completely asymptomatic.Vaginal
intermenstrual bleeding, contact post coital
bleeding or, on ocasion, a vaginal mass may
indicate the presence of malignancy. Also,
moderate pain during sexual intercourse and
vaginal discharge are symptoms of cervical
cancer. In advanced disease, there may be
signs or symptoms associated with metastases
(secondaries).
Symptoms of advanced cervical cancer may
include: loss of appetite, weight loss,
fatigue, pelvic pain, back pain, leg pain,
single swollen leg, heavy bleeding from the
vagina, leaking of urine or feces from the
vagina, and bone fractures.

Picture of a
cervical cancer

Cervical
cancer photograph

Picture of
cervical cancer - hysterectomy specimen.
Diagnosis of Cervical Cancer - Biopsy
procedures
Whereas the pap smear is an effective
screening test for pre-malignancy,
confirmation of the diagnosis of cervical
cancer or pre-cancer requires a biopsy of
the cervix. This is often done at
colposcopy, a magnified visual inspection of
the cervix aided by using an acetic acid
solution to highlight abnormal cells on the
surface of the cervix.
Further diagnostic procedures are loop
electrical excision procedure (LEEP) and
conization, in which the inner lining of the
cervix is removed to be examined
pathologically. These are carried out if the
biopsy confirms severe cervical
intraepithelial neoplasia.
Pathological
types of Cervical Cancer
Cervical intraepithelial neoplasia (CIN),
the precursor to cervical cancer, is often
diagnosed on examination of cervical
biopsies by a pathologist. Histologic
subtypes of invasive cervical carcinoma
include the following:
- squamous cell carcinoma (about
80-85%)
- adenocarcinoma
Staging
The stage of a
cancer describes its
size and whether it
has spread beyond
its original site.
Knowing the extent
of the cancer and
the grade helps the
doctors to decide on
the most appropriate
treatment.
The
stages of cervical
cancer are described
below:
Stage 1
The cancer cells are
only within the
cervix.
Stage 2
The tumour has
spread into
surrounding
structures such as
the upper part of
the vagina or
tissues next to the
cervix.
Stage 3
The tumour has
spread to
surrounding
structures such as
the lower part of
the vagina, nearby
lymph nodes, or
tissues at the sides
of the pelvic area.
Sometimes a tumour
that has spread to
the pelvis may press
on one of the
ureters (the tubes
through which urine
passes from the
kidneys to the
bladder). If the
tumour is causing
pressure on a ureter
there may be a build
up of urine in the
kidney.
Stage 2 or 3
tumours are called
locally
advanced
cervical cancer.
Stage 4
The tumour has
spread to the
bladder or bowel or
beyond the pelvic
area. This stage
includes tumours
that have spread
into the lungs,
liver or bone,
although this is not
common.
If the cancer
comes back after
initial treatment
this is known as
recurrent
cancer.
Grading
The grade of a
cancer gives an idea
of how quickly it
may develop. To find
the grade of your
cancer, your doctors
will look at a
sample of the cancer
(a biopsy) under the
microscope. It may
be graded as:
-
Grade 1
(low grade) –
the cancer cells
tend to be slow
growing, look
quite similar to
normal cells
(are 'well
differentiated')
and are less
likely to spread
than higher
grades.
-
Grade 2
(moderate grade)
– the cells look
more abnormal
and are slightly
faster-growing.
-
Grade 3
(high grade) –
the cancer cells
tend to be more
quickly growing,
look very
abnormal (are
'poorly
differentiated')
and are more
likely to spread
than low-grade
cancers.
Treatment of
Cervical Cancer
Microinvasive cancer (stage IA) is usually
treated by hysterectomy (removal of the whole
uterus including part of the vagina). For stage
IA2, the lymph nodes are removed as well. An
alternative for patients who desire to remain
fertile is a local surgical procedure such as a
loop electrical excision procedure (LEEP) or
cone biopsy.
If a cone biopsy does not produce clear
margins, one more possible treatment option for
patients who want to preserve their fertility is
a trachelectomy.0603
This attempts to surgically remove the
cancer while preserving the ovaries and uterus,
providing for a more conservative operation than
a hysterectomy. It is a viable option for those
in stage I cervical cancer which has not spread;
however, it is not yet considered a standard of
care,as few doctors are skilled in this
procedure. Even the most experienced surgeon
cannot promise that a trachelectomy can be
performed until after surgical microscopic
examination, as the extent of the spread of
cancer is unknown. If the surgeon is not able to
microscopically confirm clear margins of
cervical tissue once the patient is under
general anesthesia in the operating room, a
hysterectomy may still be needed. This can only
be done during the same operation if the patient
has given prior consent. Due to the possible
risk of cancer spread to the lymph nodes in
stage 1b cancers and some stage 1a cancers, the
surgeon may also need to remove some lymph nodes
from around the uterus for pathologic
evaluation.
It is recommended for patients to practice
vigilant prevention and follow up care including
pap screenings/colposcopy, with biopsies of the
remaining lower uterine segment as needed (every
3-4 months for at least 5 years) to monitor for
any recurrence in addition to minimizing any new
exposures to HPV through
safe sex practices until one is actively
trying to conceive.
Early stages (IB1 and IIA less than 4 cm) can
be treated with radical hysterectomy with
removal of the lymph nodes or radiation therapy.
Radiation therapy is given as external beam
radiotherapy to the pelvis and brachytherapy
(internal radiation). Patients treated with
surgery who have high risk features found on
pathologic examination are given radiation
therapy with or without chemotherapy in order to
reduce the risk of relapse.
Larger early stage tumors (IB2 and IIA more
than 4 cm) may be treated with radiation therapy
and cisplatin-based chemotherapy, hysterectomy
(which then usually requires adjuvant radiation
therapy), or cisplatin chemotherapy followed by
hysterectomy.
Advanced stage tumors (IIB-IVA) are treated
with radiation therapy and cisplatin-based
chemotherapy.
Prognosis of Cervicaql Cancer
Prognosis depends on the stage of the cancer.
With treatment, 80 to 90% of women with stage I
cancer and 50 to 65% of those with stage II
cancer are alive 5 years after diagnosis. Only
25 to 35% of women with stage III cancer and 15%
or fewer of those with stage IV cancer are alive
after 5 years. As the cancer metastasizes to
other parts of the body, prognosis drops
dramatically because treatment of local lesions
is generally more effective than whole body
treatments such as chemotherapy.
Cervical Screening - Interval
Current evidence would suggest that, if an initial screen is negative, the next screen should be three years later. If repeat smears are negative a five year screening programme would seem reasonable. The World Health Organization has recommended that in countries where resources are limited, every woman should have screening at least once in her life. The
Institute
of
Cytology
and Preventative Oncology in
India
suggest that the optimum time for once in a life-time screening would be at age 45 years.
Related Medical Abstracts - Click on the paper title:-
Cervical Screening and Prevention of Cervical Cancer
Epidemiologists in Sweden have recently reviewed the literature on screening results. They found seventeen cancer registries large enough and existing long enough to evaluate the effects of screening. Incidence rates of cervical cancer fell by more than 25% in eleven of the registries ranging from 27% in Norway to 77% in Finland. Following the initial fall in incidence with the introduction of screening, the incidence of cervical cancer has remained stable over the last 20 years in developed countries.
Figure 21.6
shows the falling rates in the incidence of cervical cancer and deaths from the disease in the UK from 1955 1985. This fall has been associated with an increase in diagnosis and treatment of pre-malignancy. The GB age-standardised (European) incidence rate for cervical cancer has decreased by 45% since 1975.
DISCLAIMERR
The aim of this web site is to provide a general guide and it is not intended as a substitute for a consultation with an appropriate specialist in respect of individual care and treatment...
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