The Catch Guide to Cervical Cancer

Description

The cervix connects the uterine cavity, where a fetus develops, to the vagina, and plays a vital role in menstruation, pregnancy, and childbirth. 

About 0.6% of women will receive a cervical cancer diagnosis at some point in their life. The average age at diagnosis is 50, though most cervical cancers are found in women between the ages of 35 and 44. It’s rare in women younger than 20. In the past several decades, increased emphasis on screening has led to an increase in diagnoses, but the mortality rate has decreased by more than half. Currently, cervical pre-cancers are far more likely to be diagnosed than invasive cervical cancer.^[1] 

Early cervical cancers and pre-cancers are unlikely to cause symptoms. As the cancer grows larger and invades surrounding tissues it commonly causes: 

• Pain or bleeding during sex
• Abnormal bleeding (such as between periods or post-menopause)
• Periods which are heavier or longer than normal
• Pelvic pain
• Unusual vaginal discharge
• Swelling of the legs
• Pain or difficulty urinating or defecating
• Blood in the urine

These symptoms may be caused by any number of health conditions, but when they are a change from your normal experience, increase in severity, or are persistent, they may indicate cervical cancer. Unexplained symptoms should always be evaluated as soon as possible by a medical professional. 

The cervix is made up of two parts, the endocervix, which is the opening that leads into the uterus, and is lined in glandular cells; and the exocervix, the portion that is visible during a pelvic exam, and which is lined in squamous cells. Different forms of cervical cancer form in each of these cells, and are characterized by distinct features and biological behaviors: 

• Squamous cell carcinoma: These cancers begin in the squamous cells of the exocervix. They usually form specifically in the “transformation zone,” where the endo- and exocervix meet. Up to 90% of cervical cancers are squamous cell carcinomas.
• Adenocarcinomas: Adenocarcinomas develop in the mucus-producing glandular cells lining the endocervix. 
• Mixed carcinomas: Rarely, cervical cancers have features of both squamous cell carcinomas and adenocarcinomas.  

Abnormal cells that are not yet cancerous may also be found in the cervix during routine screening, and in some women these abnormal cells will eventually develop into cancer (other women will clear the abnormal cells on their own). Depending on the appearance of the abnormal cells, doctors may opt to monitor them closely or remove them. Treating abnormal cells in the cervix before they become cancerous can prevent almost all cervical cancers. 

Survival rates and Incidence

Cervical cancer survival rates are based on how far the cancer has spread: 

• Localized: There is no sign the cancer has spread outside the cervix. 
• Regional: The cancer has spread to nearby structures or lymph nodes
• Distant: The cancer has spread to distant parts of the body, such as the liver or lungs. 

The 5-year survival rate for each stage is shown below:^[2]

Below is the overall incidence of cervical cancer by age group:

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Risk Factors

There are several confirmed risk factors that contribute to an individual’s risk for cervical cancer:  

• HPV Infection: Human papillomavirus (HPV) is not actually a single virus, but rather a group of more than 150 related viruses, which can be transmitted sexually or even through simple skin-to-skin contact. Some low-risk forms of the virus can cause warts on the hands, feet, mouth, or genital area. Other high-risk varieties are directly linked to cancers of the cervix, penis, mouth, throat, and anus. While many people clear the HPV virus with no side effects, infection with these high-risk forms is a major cause of cancer, and there is no treatment for the virus once contracted.
• Smoking & secondhand smoke exposure: Smoking and secondhand smoke increase your risk of many cancers, including cervical. Tobacco smoke contains numerous carcinogens that can lead to genetic mutations and uncontrolled cell growth, ultimately resulting in cancer. Quitting smoking at any age can significantly reduce the risk of cancer and other smoking-related diseases. The body begins to repair itself almost immediately after quitting, with the risk of cancer decreasing over time. Even individuals who have smoked for many years can benefit from quitting, as the risk decreases with each year of abstinence.
• Giving birth: Carrying a pregnancy to term–and especially carrying multiple pregnancies to term–correlates with an increased risk of cervical cancer. It’s thought this might be due to the change in hormones and immunosuppression that occurs during pregnancy, which may make pregnant women more susceptible to HPV infection and/or may create more favorable conditions for cancers to grow. The process of giving birth can also cause physical trauma to the cervix, which may make the cervix more susceptible to infection. 
• Family history of cervical cancer: A family history of cervical cancer, even without a known hereditary cancer syndrome, increases one’s risk of developing cervical cancer. 

Protective Measures

Several factors have been shown to have protective effects against ovarian cancer:

• HPV vaccination: The first HPV vaccination was approved by the Food and Drug Administration in 2006, and adoption has steadily increased over time. HPV vaccination, particularly at a younger age, has been shown to massively reduce the risk of developing cervical cancer. 
• Maintaining a healthy weight: Numerous studies have linked higher BMI to increased risk of various types of cancer, including cervical. Excess body fat can lead to higher levels of estrogen and insulin, as well as increased production of insulin-like growth factors. Higher BMI is also associated with chronic low-level inflammation, which can cause DNA damage over time and contribute to the development of cancer. Maintaining a healthy weight may also improve your prognosis if you are diagnosed with ovarian cancer.
• Physical activity: Regular exercise can reduce your risk of several types of cancer through a combination of physiological, hormonal, and immunological changes. It can reduce inflammation, improve immune function, improve hormonal regulation, and lower insulin levels. The American Cancer Society recommends engaging in at least 150 minutes of moderate activity or 75 minutes of vigorous activity each week. Furthermore, data indicates that individuals can see significant incremental benefit with additional exercise.
• Fruit and vegetables: Fruit and vegetables are rich in various nutrients which have been shown to have protective effects against multiple cancers, including cervical. These foods contain a variety of antioxidants, which help neutralize free radicals in the body and reduce inflammation.
• Oily fish: Oily fish (such as salmon, mackerel, trout, sardines, and herring) are known to have various health benefits. Rich in omega-3 fatty acids, protein, vitamins, and minerals, studies have shown that eating oily fish has protective effects against several types of cancer, including cervical, and that increased consumption increases these benefits.
• IUD: Use of an IUD seems to have a significant protective effect against cervical cancer. A meta-analysis of recent studies found that women who used an IUD reduced their risk by over 40%.^[3]

Screening

Early detection of cervical cancer has a dramatic impact on prognosis. The 5-year survival rate for localized cancer is around 91.1%, but drops to just 19.4% once the cancer has spread to distant parts of the body.

Depending on your age and risk factors, the optimal cervical cancer screening will vary:

• Regular pelvic exams / Pap smears: Starting at 25, annual Pap smears and pelvic exams are recommended for all women as the most effective screening for cervical cancer. Pap smears often find abnormal cells in the cervix before they have developed into cancer. Removing abnormal cells that are likely to develop into cancer effectively eliminates the cancer before it forms. 
• Colposcopy: If any abnormal cells are discovered on a pap smear, you may undergo a colposcopy, a pelvic exam aided with a magnifying instrument–the colposcope–and a weak acetic acid solution which, when applied to the cervix, highlights any abnormalities. If abnormal areas are discovered, your doctor will take a small sample of the affected tissue for biopsy during the procedure. 

Other forms of cervical biopsy: If colposcopy does not show areas of abnormal cell growth, your doctor may use an endocervical curettage (or scraping) or a cone biopsy to locate–and possibly completely remove–any abnormal cells.