Vulvar cancer: Stages and grades explained

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Doctors often use the International Federation of Gynecology and Obstetrics (FIGO) system to stage vulvar cancer.

FIGO bases vulvar cancer staging on the cancer’s location, size, and spread. Generally, the higher the stage, the more advanced the disease and the less favorable the outlook.

Staging looks at the following:

• T (tumor): Doctors consider the size and reach of the tumor and whether it presses into or invades other local areas, such as the rectum.
• N (lymph nodes): Doctors consider whether the cancer affects the local lymph nodes and the number it affects.
• M (metastasis): Doctors consider whether the cancer has spread to other areas of the body or metastasized.

Numbers or letters following the T, N, and M help provide additional details about the severity of the vulvar cancer. Higher numbers indicate a greater severity.

The National Cancer Institute (NCI) states that authors adapted the FIGO staging to the TNM staging format, and the American Joint Committee on Cancer (AJCC) incorporated FIGO staging into its system. The American Cancer Society (ACS) notes that the two systems are basically the same.

Learn more about vulvar cancer.

Stage 1 vulvar cancer breaks down into two subgroups: 1A and 1B.

Stage 1A TNM classification is as follows:

• T1a: T1a indicates the vulvar tumor spread no more than 1 millimeter (mm) into the underlying tissue and is no more than 2 centimeters (cm) in size.
• N0: N0 shows no lymph node involvement.
• M0: M0 indicates the cancer did not spread to distant parts of the body.

Stage 1B TNM classification is as follows:

• T1b: T1b indicates the tumor is larger than 2 cm or has grown more than 1 mm into the underlying tissue.
• N0: N0 indicates no lymph node involvement.
• M0: M0 means the cancer did not spread to distant tissue or organs.

Current treatments for stage 1 vulvar cancer include:

• wide local excision of the tumor
• radical local excision, which involves removing the tumor and lymph nodes in the groin and upper thigh
• modified radical vulvectomy (radical vulvectomy), which involves removal of most of the vulva as well as lymph nodes in the groin and upper thigh, possibly coupled with radiation
• radical local excision and removal of sentinel lymph nodes, which may involve follow-up radiation therapy
• radiation therapy

Stage 2 vulvar cancer means the cancer grew in size or invaded more tissue.

Stage 2’s TNM classification breaks down into the following:

• T2: T2 indicates the vulvar tumor may be any size but has grown into the anus, the lower third of the vagina, urethra, or anus.
• N0: N0 means that no lymph node involvement occurred at the time of diagnosis.
• M0: M0 means the cancer did not spread to other areas of the body.

Treatment options for stage 2 vulvar cancer typically involve the same surgical and radiation options available for stage 1 vulvar cancer.

Stage 3 vulvar cancer includes three substages:

• 3A
• 3B
• 3C

Stage 3A TNM includes the following:

• T1 or T2: The tumor is located in the vulva (T1) and may be growing into the vagina, anus, or lower urethra (T2).
• N1: The cancer spread to one nearby lymph node with an area of spread of 5 mm or more. Alternatively, the tumor spread to one or two nearby lymph nodes with both areas of spread less than 5 mm.
• M0: Vulvar cancer did not spread to distant tissue.

Stage 3B TNM includes the following:

• T1 or T2: The tumor is located in the vulva (T1) and may be growing into the vagina, anus, or lower urethra (T2).
• N2a: The cancer spread to three or more nearby lymph nodes with all areas of cancer spread less than 5 mm.
• N2b: The cancer spread to two or more lymph nodes with each area of spread 5 mm or greater.
• M0: The cancer did not spread to distant areas of the body.

Stage 3C’s TNM includes the following:

• T1 or T2: The tumor is located in the vulva (T1) and may be growing into the vagina, anus, or lower urethra (T2).
• N2c: The cancer spread to nearby lymph nodes and began extracapsular spread. This means it started to grow through the outer covering of at least one lymph node.
• M0: The cancer did not spread to distant areas of the body.

For stage 3 vulvar cancer, a doctor may recommend a modified radical vulvectomy or radical vulvectomy with removal of lymph nodes in the groin and upper thigh. They may suggest the use of radiation therapy along with surgery.

In some cases, they may recommend either radiation therapy alone or chemotherapy and radiation therapy with surgery following. Radiation or chemotherapy may help shrink the tumor before removal in these cases.

Another option may be the use of radiation therapy with or without chemotherapy.

Stage 4 vulvar cancer includes two subtypes: 4A and 4B.

Stage 4A’s TNM classification breaks down into two different groups. The first includes:

• T1 or T2: The tumor is located in the vulva (T1) and may be growing into the vagina, anus, or lower urethra (T2).
• N3: The cancer spread to nearby lymph nodes and either became stuck (fixed) to the tissue beneath or caused the formation of an ulcer in the lymph node(s).
• M0: The vulvar cancer did not spread to distant areas of the body.

The second TMN group for stage 4A includes:

• T3: The cancer spread beyond nearby tissues to the pelvis, rectum, bladder, or upper part of the vagina or urethra.
• N any: The cancer may or may not have spread to nearby lymph nodes. It can include any level of lymph node involvement.
• M0: Vulvar cancer did not spread to distant areas of the body.

Stage 4B’s TNM breaks down into the following:

• Any T: Any T indicates that the tumor at this stage can be any size.
• Any N: Any N means that the cancer may or may not have spread to nearby lymph nodes.
• M1: The vulvar cancer spread to distant tissue or organs, such as bones or lungs.

The NCI notes that treatment for stage 4 vulvar cancer may involve:

• surgery, such as radical vulvectomy or pelvic exenteration
• radiation therapy and surgery
• radiation therapy OR chemotherapy and radiation therapy with surgical follow-up
• radiation therapy with or without chemotherapy.

Cancer grade refers to how the cancer cells look under a microscope.

A low grade means the cancer appears most like normal cells that the cancer grew from. Grade 3 cells appear abnormal.

Cancer grade can affect the outlook. The higher the grade, the more aggressive the cancer tends to be.

Grade 1

Grade 1 cells look a lot like the normal cells of the vulva. Doctors may refer to the cells as low grade or well-differentiated. Often, grade 1 cells tend to spread less and grow slower than higher-grade cells.

Grade 2

Grade 2 means the cells look less normal and have a higher chance of spreading compared with cells in grade 1. Doctors may refer to it as moderately differentiated or moderate-grade.

Grade 3

Vulvar cancer cells in grade 3 look very abnormal and not like normal vulva cells. They tend to be fast-growing and more likely to spread. Doctors may refer to this grade as poorly differentiated or high grade.

The following are answers to frequently asked questions about vulvar cancer.

What is the life expectancy of a person with vulvar cancer?

According to the NCI’s Surveillance, Epidemiology, and End Results (SEER) Program, the 5-year relative survival rate for vulvar cancer was 69.4% between the years 2013 and 2019.

Several factors can affect life expectancy. A small 2021 study found that the three most significant factors included the involvement of lymph nodes, the stage of the cancer, and the use of chemotherapy or radiation.

What are the symptoms of stage 1 vulvar cancer?

Not everyone will experience symptoms in the early stages of vulvar cancer. Those who do may notice one or more of the following:

• pain and tenderness
• itching in the area that does not stop
• changes in skin in the area
• ulcer, lump, or wart-like bumps
• unusual bleeding

Where does vulvar cancer usually spread to first?

As the vulvar tumor grows, it typically pushes into the vagina, anus, rectum, or bladder. It may also affect the local lymph nodes when the tumor is still small.

Vulvar cancer breaks down into four stages with various subtypes. The stages, TNM classification, and grade of the cancer can affect a person’s outlook and treatment options.

A person can discuss their cancer’s stage and grade with their healthcare professional, who can answer questions about treatments, outlook, and more.