The cervix is the lower part of the uterus, and connects the uterus to the vagina. Although it is technically part of the uterus, cervical cancer is classified differently from uterine cancer as the causes, diagnosis and treatment is different.
Cervical cancer is caused predominantly by persistent infection with the human papilloma virus (HPV). The incidence of cervical cancer has reduced dramatically over the past few decades as a result of the screening, and the incidence is expected to continue to decline as vaccination against some types of HPV further reduces the likelihood of developing this disease.
Diagnosis is often made following an abnormal screening test, which is now being done via the new Cervical Screening Test, which has replaced the pap test in Australia. This is followed by further assessment and examination, such as a colposcopy examination of the cervix, and biopsy. In some women, diagnosis may occur after symptoms of vaginal bleeding or pain.
Other tests may be required which include:
PET (positron emission tomography)
PET is a special scan that uses very small amounts of a radioactive chemical called FDG (which is like a sugar), to produce images of areas in the body where there is more activity. These ‘hot spots’ can help indicate whether a cancer may have spread outside the cervix or pelvis, and can sometimes be used to monitor response to treatment.
MRI (magnetic resonance imaging)
MRI is a scan that uses a strong magnetic field and radio waves to give detailed pictures of soft tissues, muscles and fat and internal organs of the body. It can give different information than a CT (computed tomography – ‘CAT’ scan) that makes it useful to evaluate the extent of the cervical cancer.
Types and staging of cervical cancer
Like most cancers, cervical cancers have different types, depending on how the cells look like under the microscopic (histologic types). The most common subtype is called squamous cell carcinoma, while most of the remaining are adenocarcinomas. Rarely both types can be present and these are called adenosquamous carcinoma.
The stage of any cancer describes how far the cancer has spread from the organ where it started. The stage determines how serious the cancer is, and what the most appropriate treatment is. The stage can be 1, 2, 3 or 4. Stage I is present only in the cervix, whereas stage 4 cancer has spread outside the cervix either to invade the bladder or rectum, or to other parts of the body, such as the lung. If cervical cancer spreads to lung, it is still called cervical cancer and not lung cancer, as any cancer that spreads to other organs still looks like the original tissue where it had started.
Cervical cancer is also described by another measure, called ‘grade’, which describes the degree to which the cancer cells are similar or different to non-cancerous cells. Grades 1 and 2 cancers are less aggressive, and spread to other organs or tissue less often than higher grade cancers (grade 3).
Treatment for cervical cancer will depend on a number of factors, including the type, grade and stage of the cancer, as well as age, other health problems, and patient preferences for treatment and expected side effects.
Once sufficient information to make a diagnosis and information on stage is available, the treating team typically meets to discuss these findings at a multi-disciplinary ‘Tumour Board’ which includes surgeons (gynaecologic oncologist), radiation and medical oncologists, pathologists, radiologists and others. A recommendation is then made as to the proposed treatment approach, and this is discussed with the patient by the relevant cancer doctor. Treatments recommended may include surgery, radiation, chemotherapy, or a combination of these approaches.
Early stages of cervical cancer are treated with surgery. This is typically an operation called radical hysterectomy to remove the uterus, cervix and surrounding tissues, as well as removal of the pelvic lymph nodes (pelvic lymph node dissection). In some cases, for example when there is a desire to preserve fertility and the cancer is very early, a cone biopsy or less radical surgery may be considered. Once surgery is performed, all the tissues removed are carefully examined by a specialist pathologist to determine the extent of disease and any findings that may not have been known by scans alone.
Radiotherapy uses high-energy ionising radiation (like x-rays or gamma rays) to kill cancer cells. There are two types of radiotherapy used for cervical cancer. Brachytherapy, is internal radiotherapy that is given by inserting radioactive seeds in a device into the vagina near the cervix (and sometimes in the cervix). External radiation is given by using external beams, much like a normal x-ray. It is typically given 5 days a week for 4 to 6 weeks, although each treatment is very quick. The radiation plan is developed by a radiation oncologist, who is a cancer doctor that specialises in radiation treatment.
In cervical cancer, radiation therapy may either be given following surgery to reduce the risks of recurrence, or as a combination treatment with chemotherapy (concurrent chemoradiotherapy), given instead of surgery, but still with the aim of curing the cancer. This is because in some cases of cervical cancer, surgery alone will not be sufficient to eliminate all microscopic cancer cells, and concurrent chemoradiotherapy provides the same chances of cure but less side effects than expected when all three treatments are provided.
Side effects of radiotherapy will depend on which type of radiation will be given, but can include skin changes, bowel disturbances such as diarrhea, nausea and vomiting; and fatigue. Most of the side effects improve once treatment is completed, but some effects can persist for longer.
Chemotherapy are drugs used to fight cancer. In cervical cancer, they are usually given through a needle in the vein. Chemotherapy is used as a component of concurrent chemoradiotherapy, where typically a single chemotherapy drug is given once a week for 5-6 weeks, starting at the same time as external radiotherapy. In this setting, chemotherapy is considered a ‘radio-sensitiser’, enhancing the ability of radiotherapy to kill cancer cells.
In more advanced cervical cancer which has spread outside the pelvis or to distant organs, sometimes chemotherapy is given alone, and in this case more than one drug is used. Chemotherapy is also used in cervical cancer that recurs after prior therapy, or which persists after completion of chemoradiotherapy.
Side effects of chemotherapy include fatigue and gut symptoms such as nausea and vomiting; and the diarrhoea caused by radiotherapy can be worse when chemotherapy is also given. Drugs that are often used in metastatic or recurrent disease, such as paclitaxel, can cause hair loss and can cause damage to nerves resulting in numbness, tingling or burning sensations, and sometimes pain, especially of the hands and feet. Most side effects related to chemotherapy can be managed with other supportive treatments or drugs and tend to improve once treatment is finished.
Recurrent cervical cancer
Although most cervical cancers are cured after initial treatment, some cancers can recur months or years after initial treatment. Treatments for recurrent cervical cancer depend on the location of recurrence, and what prior treatments have been given. There can be a role for surgery, radiotherapy, or chemotherapy, as well as consideration of suitable clinical trials of new treatments.
Clinical trials are a type of research studies that may be testing a new treatment approach or new drugs. They are the best way to develop new treatments to treat cancer, and often are comparing a new approach to current standard treatments or testing a new treatment when there is no current beneficial treatment. They also are one way of getting the newest treatment for cancer, especially when treatment options are not effective or stop working.
Other treatments may also be recommended to help prevent and/or control some of the symptoms of endometrial cancer and symptoms related to the treatments. These are referred to as Supportive Care.