Cervical cancer staging
Cervical cancer staging is the assessment of cervical cancer to determine the extent of the spread of cancer beyond the cervix.[12] This is important for determining how serious the cancer is and to create the best treatment plan.[13]
Cervical cancer
Early: none[2]
Later: vaginal bleeding, pelvic pain, pain during sexual intercourse[2]
Over 10 to 20 years[3]
Squamous cell carcinoma, adenocarcinoma, others[4]
Smoking, weak immune system, birth control pills, starting sex at a young age, many sexual partners or a partner with many sexual partners[2][4][7]
Cervical screening followed by a biopsy[2]
Regular cervical screening, HPV vaccines, sexual intercourse with condoms,[8][9] sexual abstinence
Five-year survival rate:
68% (US)
46% (India)[10]
604,127 new cases (2020)[11]
341,831 (2020)[11]
Cervical cancer is a type of gynecological cancer that begins from cells lining the cervix, the lower part of the uterus.[14] Cervical cancer begins when the cells that line the cervix become abnormal and grow in a pattern that is atypical for non-cancerous cells.[14] Cervical cancer is typically first identified with an abnormal pap smear.[14] The final diagnosis of cervical cancer, including the stage of the cancer, is confirmed with additional testing.[12]
Cancer staging is determined by where the tumor is located, the size of the tumor, and how much the tumor has spread beyond where it originally began, such as to nearby lymph nodes or different parts of the body.[13]
Cancer staging is described on a spectrum from stage 0 to stage IV. Stage 0 describes pre-cancerous or non-invasive types of tumors. Stage IV is used to describe cancers that have spread throughout a significant part of the body. In general, the greater the stage of cancer, the more aggressive the disease and the worse the prognosis.[13]
Cervical cancer staging is described by the International Federation of Gynecology and Obstetrics (FIGO).[12][15] In 2018, FIGO released the most recent guidelines for cervical cancer staging.[16] These guidelines recommend the use of various physical examinations, types of imaging, and biopsies to determine the stage of cervical cancer.[16]
Cervical cancer[edit]
Cervical cancer is the abnormal growth of the cells that line the cervix, resulting in the cells growing out of control and potentially spreading to areas outside of the cervix.[14]
The cervix is the lower part of the uterus. It connects the upper part of the uterus with the vagina. The cervix is divided into two parts based on the types of cells. The outer portion of the cervix is called the ectocervix, while the inner portion of the cervix is the endocervix. These two portions of the cervix have different types of cells. The area where the endocervix and ectocervix meet is known as the transformation zone. Most cervical cancers arise from the cells in the transformation zone.[14]
Cervical cancer screening occurs with pap smears performed by an obstetrician-gynecologist. During a pap smear, doctors collect a sample of the cells from the cervix to look at under a microscope to examine for any abnormalities or signs of pre-cancerous changes.[17] While many abnormalities on pap smears are not indicative of cervical cancer,[14] the doctor may recommend additional testing to gain a better understanding of the cervical cells.[18] Additional testing that may be performed includes an endocervical curettage, colposcopy, or cervical conization.[18] Each of these procedures allows for the collection of a biopsy of the cells of the cervix.[18]
Abnormalities of cervical cells, or dysplasia, develop over time and along a continuum. There are several types of abnormalities of cervical cells known as pre-cancerous changes. These pre-cancerous changes are known as cervical intraepithelial neoplasm (CIN) and squamous intraepithelial lesion (SIL), based on whether the results are from a biopsy or a pap smear. CIN and SIL are graded from 1 to 3 based on the degree of change observed. CIN 1, 2, and 3 all represent pre-cancerous findings.[14]
The main types of cervical cancer include squamous cell carcinomas and adenocarcinomas. Nearly 90% of cervical cancers are squamous cell carcinomas. Cervical cancers may also be a mix between squamous cell carcinomas and adenocarcinomas, known as adenosquamous carcinoma.[14]
Cervical cancer spreads directly from the cervix into surrounding organs and via the lymphatic system.[16] When spreading via the lymphatic system, cervical cancer will spread to nearby lymph nodes, including the obturator, external iliac, and internal iliac lymph nodes.[16] Nearby structures that cervical cancer may spread to directly include the peritoneum, vagina, uterus, bladder, and rectum.[16] If cervical cancer has spread to distant organs, such as the liver, lungs, or skeleton, this represents a late finding and significant disease.[16] The degree of spread of cancer to areas beyond the cervix is important in determining the stage of cervical cancer.[16]
Overview of staging[edit]
Staging is the process of determining the type of cervical cancer and the extent the cancer has spread beyond the cervix to local or distant parts of the body.[12] To determine the stage of the cancer, various modalities may be used including physical examination, biopsies, pathological examinations, and imaging, including MRI, ultrasound, CT, and PET scans.[16] The information gathered from all of these modalities is put together to determine the cancer stage.[16] FIGO guidelines recommend assigning a lower stage whenever possible.[16] The cervical cancer stage assigned at initial diagnosis cannot be altered later, regardless of recurrence or later disease spread.[19]
Staging modalities[edit]
Biopsy[edit]
A biopsy, or sample of the tissue, is the first step in determining the type and extent of cancer. This biopsy may be obtained through a punch biopsy, LEEP (loop electrosurgical excision procedure), or cone biopsy. These procedures allow the doctor to obtain a sample of the cancerous tissue to look at under a microscope. By examining the size of the cancer, the margins of the biopsy sample, and the type of abnormal cells, the type of cancer can be determined.[16]
Biopsy of nearby lymph nodes may also be necessary to determine if the cervical cancer has spread lymphatically. This may be done via fine-needle aspiration, minimally invasive surgery, or laparotomy (open incision of the abdomen).[16] Typically, these procedures are not done until after there is confirmation of cervical cancer and after imaging is performed, if possible.
Pathology[edit]
Following the collection of biopsies of the cervical cancer and areas where it may have spread, the cells of the cancer will be looked at under a microscope. This is vital in determining the stage of the cancer. There are several different ways that pathologists may classify the cancer. All cancers of the cervix must be confirmed under a microscope and are determined to be cervical in origin if the primary source of the cancer is the cervix.[16]