Oral Cancer Stages / Staging

Staging is a system that describes the extent of cancer in the body. Our oral cancer doctors use a variety of diagnostic tests to develop an individualized treatment plan for you.

TNM Staging

Cancer staging is the process used to determine how much a cancer has spread.

Oral cancer stages are based on the results of physical exams, endoscopies, biopsies, and any imaging tests (CT scan, MRI, chest X-ray, and/or PET scans).

The American Joint Committee on Cancer (AJCC) developed the TNM cancer staging system to evaluate three primary factors when it comes to treating cancer: T, N and M:

• T refers to the size of the primary tumor and to which, if any, tissues in the oral cavity and oropharynx the cancer has spread.
• N describes the involvement of lymph nodes near the primary tumor. Lymph nodes are small, bean-shaped clusters of immune system cells that are key to fighting infections and are usually one of the first sites in the body to which cancer spreads.
• M indicates whether the cancer has spread (metastasized) to other areas of the body. With oral cancer, the most common site of metastases is the lungs, followed by the liver and bones.

Your doctor will assign T, N, and M values to the disease based up its microscopic appearance. Your care team at CTCA will thoroughly review your medical history, family history, and other factors to develop an individualized treatment plan for you.

T Categories for Oral Cavity and Oropharyngeal Cancers

These measurements refer to the primary oral cancer tumor.

TX: primary tumor cannot be assessed; information not known.

TO: no evidence of primary tumor Tis: carcinoma in situ. This means that the disease is still localized, or contained within the top layers of cells lining the oral cavity and oropharynx. Cancer cells have not invaded the deeper layers of oral or oropharyngeal tissue.

T1: tumor is 2 cm across or smaller.

T2: tumor is larger than 2 cm across, but smaller than 4 cm.

T3: tumor is larger than 4 cm across.

T4 is divided into two subgroups:

• T4a: the tumor is growing into nearby structures. At this stage, the oral cancer is called a moderately advanced local disease. The areas to which cells have spread vary according to the type of oral cancer:
  • For oral cavity cancers: the tumor is growing into nearby structures such as the bones of the jaw or face, deep muscle of the tongue, skin of the face, or maxillary sinus.
  • For lip cancers: the tumor is growing into nearby bone, the inferior alveolar nerve (the nerve to the jawbone), the floor of the mouth, or the skin of the chin or nose.
  • For oropharyngeal cancers: the tumor is growing into the larynx (voicebox), the tongue muscle, or bones such as the hard palate or jaw.
• T4b: the tumor has grown through nearby structures and into deeper areas or tissues. At this stage, the cancer is called very advanced local disease, and may include any of the following conditions:
  • The tumor is growing into other bones, such as the pterygoid plates (in the skull) and/or the skull base. This type of spreading can occur with any oropharyngeal or oral cancer.
  • The tumor surrounds the internal carotid artery. This type of spreading can occur with any oropharyngeal or oral cancer.
  • For lip and oral cavity cancers: the tumor is growing into an area called the masticator space
  • For oropharyngeal cancers: the tumor is growing into a muscle called the lateral pterygoid muscle, which is used for chewing.
  • For oropharyngeal cancers: the tumor is growing into the nasopharynx (the area of the throat that is behind the nose).

N Categories for Oral Cavity and Oropharyngeal Cancers

NX: nearby lymph nodes cannot be assessed; information not known.

N0: the oral cancer has not spread to any nearby lymph nodes.

N1: the cancer has spread to one lymph node on the same side of the head or neck as the primary tumor. This lymph node is smaller than 3 cm across.

N2 is divided into three subgroups:

• N2a: the oral cancer has spread to one lymph node on the same side as the primary tumor, and the lymph node measures 3–6 cm across.
• N2b: the cancer has spread to 2 or more lymph nodes on the same side as the primary tumor. No lymph nodes are larger than 6 cm across.
• N2c: the oral cancer has spread to one or more lymph nodes on both sides of the neck or on the side opposite the primary tumor. No lymph nodes are larger than 6 cm across.
• N3: the cancer has spread to a lymph node that measures more than 6 cm across.

M Categories for Oral Cavity and Oropharyngeal Cancers

M0: no distant spread.

M1: the oral cancer has spread to distant sites outside the head and neck region (for example, the lungs, liver or bones).

Cancer Stage Groupings

Oral cancer is classified as stage 0, 1, 2, 3 or 4 according to the TNM measurements. Your doctor will assign a stage to the disease based upon this information, and will work with you to create a treatment plan.

Characteristics of each of the cancer stages include:

Stage 0: Tis, N0, M0 Carcinoma in situ. The cancer is only growing in the epithelium, the outermost layer of tissue in the oral cavity or oropharynx. No cancer cells are present in deeper layers of tissue, nearby structures, lymph nodes, or distant sites.

Stage I: T1, N0, M0 The primary oral cancer tumor is 2 cm across or smaller, and no cancer cells are present in nearby structures, lymph nodes, or distant sites.

Stage II: T2, N0, M0 The tumor measures 2–4 cm across, and no cancer cells are present in nearby structures, lymph nodes, or distant sites.

Stage III: One of the following applies –

• T3, N0, M0: the tumor is larger than 4 cm across, and no cancer cells are present in nearby structures, lymph nodes, or distant sites.

or

• T1–3, N1, M0: the tumor is any size but has not grown into nearby structures or distant sites. However, cancer cells are present in one lymph node, which is located on the same side of the head or neck as the primary tumor and is smaller than 3 cm across.

Stage IVA: One of the following applies –

• T4a, N0 or N1, M0: the oral cancer tumor is any size and is growing into nearby structures. Cancer cells may not be present in the lymph nodes, or they may have spread to one lymph node, which is located on the same size of the head or neck as the primary tumor and is smaller than 3 cm across. Cancer has not spread to distant sites.

or

• T1–4a, N2, M0: the tumor is any size and may or may not have invaded nearby structures, it has not spread to distant sites, and one of the following is true:
  • cancer cells are present in one lymph node, located on the same side of the head or neck as the primary tumor and measuring 3–6 cm across (N2a)
  • cancer cells are present in one lymph node on the opposite side of the head or neck and measuring less than 6 cm across (N2b)
  • cancer cells are present in 2 or more lymph nodes, all smaller than 6 cm across and located on either side of the head or neck (N2c)

Stage IVB: One of the following applies –

• T4b, any N, M0: the tumor has invaded deeper areas and/or tissues. It may or may not have spread to lymph nodes and has not spread to distant sites.

or

• Any T, N3, M0: the tumor is any size and may or may not have grown into other structures. It has spread to one or more lymph nodes larger than 6 cm across, but has not spread to distant sites.

Stage IVC: Any T, Any N, M1

The oral cancer tumor is any size and may or may not have spread to lymph nodes. Cancer cells have spread to distant sites, most commonly the lungs.

Recurrent Oral Cancer

Recurrent or relapsed disease means that the cancer has returned after treatment. Recurrent disease does not have a TNM classification or a staging system number. When oral cancer recurs in the mouth or throat, it is called a local recurrence. When it recurs in the lymph nodes, it is called a regional relapse. When other parts of the body, such as the lungs, are involved, it is called a distant recurrence.

Although early-stage oral cancer may be easier to treat than more advanced disease, treatment options are available for all patients. Your doctor will explain the options that may work for you, so that your treatment can be as effective as possible.

Next Topic: Oral Cancer Treatment