Sinus cancer stages

Staging sinus cancer may involve a multi-step process that includes several tests, measurements and additional factors so the care team can pinpoint the cancer’s size, extent and aggressiveness.

How is sinus cancer staged?

The American Joint Committee on Cancer (AJCC) developed the TNM cancer staging system to evaluate three primary factors when it comes to treating cancer, including sinus and other. Below are explanations of what T, N and M mean:

T (tumor): This refers to the size of the primary tumor. It also evaluates to what extent, if any, the cancer has spread to tissues in the nasal cavity and paranasal sinuses and neighboring skull bones. Sometimes, sinus cancers are categorized as T1, T2, etc., instead of by stages.

N (node): This describes the involvement of lymph nodes near the primary tumor. Lymph nodes are small, bean-shaped clusters of immune system cells that are crucial to fighting infections. They are usually one of the first sites in the body where cancer spreads.

M (metastasis): This indicates whether the cancer has spread (metastasized) to other areas of the body. With sinus cancer, the most common site of metastases is the lungs. Bones are the second most common site.

During the sinus cancer staging process, the doctor will assign T, N and M values to the disease based on its microscopic appearance. The care team will thoroughly review the patient's medical history, family history and other factors to develop an individualized treatment plan.

Stages of sinus cancer

Stage 0 sinus cancer

A stage 0 sinus cancer is also known as carcinoma in situ. It means that abnormal cells have been detected in the innermost lining of the maxillary sinus, the nasal cavity or the ethmoid sinus. The abnormal cells could become cancerous and spread to normal tissue.

Stage 1 sinus cancer

A stage 1 sinus cancer means the primary tumor is in one sinus, one section of the maxillary sinus mucous membranes, or in the ethmoid sinus or nasal cavity. It also means the cancer could spread to bone.

Stage 2 sinus cancer

A stage 2 sinus cancer involves more than one sinus, either in the nasal cavity or the ethmoid sinus. It also means the tumor has spread to bone near to the maxillary sinus. This stage includes the mouth and the nose, but not the bone at the back of the maxillary sinus or the base of the skull.

Stage 3 sinus cancer

A stage 3 sinus cancer means the tumor has spread into muscle and tissues under the skin, at the eye socket, the ethmoid sinuses or bone at the back of the maxillary sinus or at the base of the skull. In this stage, cancer cells have spread to one lymph node (3 cm or smaller) on the neck near the cancer and to areas that could include the bone between the eyes, the roof of the mouth, the eye socket, nasal cavity, ethmoid sinus or the maxillary sinus. When a single lymph node is involved, the cancer is automatically identified as stage 3 sinus cancer.

Stage 4 sinus cancer

Stage 4 sinus cancer is determined by various factors, including a tumor that has spread to the brain, skin or frontal sinus/sphenoid (center of the forehead). When more than one lymph node is involved, the cancer is automatically defined as stage 4 sinus cancer. The sub-stages of stage 4 sinus cancer are:

• Stage 4A: At this stage, one of the following applies:
  • The tumor has spread to one lymph node (larger than 3 cm, but not exceeding 6 cm) on the neck near the cancer.
  • Cancer cells have spread to more than one lymph node (not exceeding 6 cm) on the same side of the neck as the original tumor.
  • Cancer cells have spread to lymph nodes (not exceeding 6 cm) on both sides of the neck, or to the opposite side of the location of the original neck tumor.
  • Cancer cells have spread to either the maxillary sinus lining and/or bones near the maxillary sinus, including the nose and the roof of the mouth.
  • Cancer cells have spread to tissues under the skin, the base of the skull, the ethmoid sinuses or the eye socket or the front of the eye, behind the jaw, the skin of the cheek or the sphenoid or frontal sinuses.

• Stage 4B: At this stage, one of the following applies:
  
  • Cancer cells have spread through head nerves to the brain, mid-skull, at the rear of the eye or the throat at the back of the nose and at the base of the skull.
  • Cancer cells have been discovered in the neck in one or multiple lymph nodes (no size restrictions) or in a lymph node larger than 6 cm.
  • Cancer cells have been detected either in or near the maxillary sinus.

• Stage 4C: Cancer cells have been detected in or around the maxillary sinus or nasal cavity, and ethmoid sinus and lymph nodes, and may have spread to organs, including the lungs.

Sinus cancer survival rate

One way people battling cancer can estimate life expectancy is to review the five-year relative survival rate for that type of cancer. A five-year relative survival rate shows the likelihood that a person with a specific type and stage of cancer may live for at least five years after the diagnosis, compared with people who don't have cancer. The rate includes the life expectancy of patients who are still in treatment and those who have finished treatment and have no further evidence of disease.

The National Cancer Institute SEER Program bases the survival rate for nasal cavity and paranasal sinus cancers on how far the cancer has spread:

• Localized—The cancer has not spread outside of the nasal cavity or sinus. The five-year survival rate for localized nasal cavity and paranasal sinus cancer is about 86 percent.
• Regional—The cancer has spread from the sinus area to nearby lymph nodes or structures. The five-year survival rate for regional nasal cavity and paranasal sinus cancer is about 52 percent.
• Distant—The sinus cancer has spread to structures that are further away from the sinuses, such as the liver. The five-year survival rate for distant nasal cavity and paranasal sinus cancer is lower—about 43 percent.
  

Next topic: How is sinus cancer diagnosed?