Cervical cancer - what is, symptoms, causes and treatment
What is Cervical Cancer
A malignant (cancerous) tumor that originates in a woman’s CERVIX. The cervix is a thick neck of tissue that joins the VAGINA and the UTERUS. INFECTION with the HUMAN PAPILLOMAVIRUS (HPV) accounts for nearly all cervical cancer, though only about 15 of the 100 or so strains of HPV are connected with cervical cancer and only a small percentage of women who have HPV infection with one of those strains actually develops cervical cancer.
Cervical cancer tends to follow a predictable path of development that takes many years to evolve, typically 10 years or longer. Because of this, with early detection cervical cancer is one of the most curable forms of cancer. The path of development for cervical cancer begins with slight changes in the cells of cervical tissue, called cervical DYSPLASIA. Though not cancer, dysplasia is a circumstance of irregular cell growth. All cervical cancer begins as cervical dysplasia. Because of this, even though only a small percentage of cervical dysplasia become cancer doctors consider cervical dysplasia a broad classification of cell abnormalities that range from precancerous to cancerous.
Doctors call moderate to severe cervical dysplasia, which is precancerous, CERVICAL INTRAEPITHELIAL NEOPLASIA (CIN). Doctors believe about two thirds of untreated cervical dysplasia progresses to cancer. The PAP TEST, a laboratory examination of cells swabbed from the cervix, can detect cervical dysplasia, CIN, and other changes in cervical tissue. A Pap test is part of a routine PELVIC EXAMINATION.
Symptoms of Cervical Cancer and Diagnostic Path
Cervical cancer often shows no symptoms until it spreads outside the cervix, which is why routine Pap tests are so crucial in its detection. When symptoms are present they may include
- watery, sometimes blood-tinged discharge
- vaginal bleeding between menstrual periods or after MENOPAUSE
- vaginal bleeding during or after SEXUAL INTERCOURSE
- unusually heavy or prolonged menstrual periods
- low back discomfort
- unexplained tiredness, lack of energy, or fatigue
- URINARY URGENCY or URINARY FREQUENCY
The diagnostic path begins with pelvic examination, Pap test, and HPV testing, including HPV DNA. COLPOSCOPY (examination of the cervix with a special lighted microscope) provides additional information about the location and extensiveness of the cancer. Cervical biopsy (laboratory examination of tissue samples taken from the cervix) provides definitive diagnosis. Diagnostic imaging procedures such as COMPUTED TOMOGRAPHY (CT) SCAN or MAGNETIC RESONANCE IMAGING (MRI) may show the extent to which the cancer has metastasized to locations within or distant from the pelvis. The pathologist determines the grade (degree of abnormality of the cells) and stage (extent of the tumor) from the biopsy tissue samples. STAGING AND GRADING OF CANCER is important for determining appropriate CANCER TREATMENT OPTIONS AND DECISIONS.
| BASIC STAGING OF CERVICAL CANCER | ||
|---|---|---|
| Stage | Meaning | Treatment Options |
| cervical intraepithelial neoplasia (CIN2/CIN3) | cells are abnormal but precancerous and confined to a localized area of the CERVIX | cryosurgery, laser surgery, loop electrosurgical procedure (LEEP), or excisional conization to remove abnormal cells frequent and regular PAP TEST and COLPOSCOPY |
| CIN4/stage 0/carcinoma in situ | cancer remains confined to the cells of its origin | cryosurgery, laser surgery, LEEP, or excisional conization to remove abnormal tissue frequent and regular Pap test and colposcopy |
| stage 1 | cancer remains confined to a small, clearly defined area of the cervix stage 1A is microscopic; stage 1B is barely visible to the unaided eye |
stage 1A: total HYSTERECTOMY frequent and regular Pap test and colposcopy stage 1B: modified radical HYSTERECTOMY with SENTINEL LYMPH NODE DISSECTION and adjuvant RADIATION THERAPY and/or CHEMOTHERAPY or high-dose external beam radiation combined with internal seeding |
| stage 2 | cancer has spread to other structures within the pelvis but not to distant organs stage 2A involves the upper VAGINA; stage 2B involves parametrial tissue |
high-dose external and internal radiation therapy in combination with platinum-agent chemotherapy |
| stage 3 | cancer has spread widely within the pelvis and may involve the lower vagina and ureters stage 3A involves the lower vagina but not the pelvic wall; stage 3B involves the pelvic wall or the pelvic LYMPH nodes |
combination chemotherapy palliative radiation therapy clinical trials |
| stage 4 | cancer has spread to distant organs or recurred (come back) after treatment stage 4A involves lower abdominal organs; stage 4B involves distant organs |
combination chemotherapy palliative radiation therapy clinical trials |
Cervical Cancer Treatment Options and Outlook
Cervical cancer is almost always curable with minimally invasive treatment when doctors detect it as CIN or stage 1. Stage 2 and stage 3 cervical cancers require more invasive treatments and have lower potential for cure. The primary treatment of choice for most stage 1 cervical cancers is surgery to remove the tumor, the entire cervix, or, in more advanced stages, the cervix and adjacent tissues such as the upper vagina and often the uterus (total or modified radical HYSTERECTOMY). Adjuvant (follow-up) treatment may include CHEMOTHERAPY or RADIATION THERAPY. High-dose radiation therapy (external beam and internal seeding) in combination with chemotherapy, is the primary treatment of choice for most stage 2 and stage 3 cervical cancers as these have usually spread beyond the scope of surgery, though surgery may be an option for stage 2 cervical cancer that remains confined to the upper vagina. The treatment of choice for stage 4 cervical cancer is combination chemotherapy with palliative radiation therapy to relieve symptoms of obstructive tumors.
| CHEMOTHERAPY AGENTS TO TREAT CERVICAL CANCER | |
|---|---|
| carboplatin | cisplatin |
| gemcitabine | paclitaxel |
| topotecan | vinorelbine |
Risk Factors and Preventive Measures
The key risk factors for cervical cancer are HPV infection with one of the few strains of HPV linked to cervical cancer, multiple sexual partners, and cigarette smoking. The HPV vaccine prevents infection with HPV types 6, 11, 16, and 18, the strains of HPV associated with genital warts and cervical cancer. Health experts recommend HPV vaccination for girls beginning at age 12, though women to age 26 can receive the vaccine. Because HPV accounts for nearly all cervical cancer, measures to reduce exposure to HPV infection (such as condom use and mutual monogamy) are also crucial. Routine pelvic examination with Pap test can detect cervical cancer in its earliest, curable stages.
See also BREAST CANCER; CONTRACEPTION; ENDOMETRIAL CANCER; HIV/AIDS; SEXUAL HEALTH; SEXUALLY TRANSMITTED DISEASE (STD) PREVENTION; SURGERY BENEFIT AND RISK ASSESSMENT.
