Diagnosis begins with a thorough office examination. Your doctor may choose to examine your sinonasal tract and nasopharynx using an endoscope — a long, thin tube with a light and camera that takes pictures of internal structures. These pictures are displayed on a computer monitor for analysis and diagnosis.

Other imaging tests your doctor may conduct include:

• CT scan and MRI. These tests are used to further characterize tumors of the sinus cavities or nasal passageway. Generally, the MRI is considered a little more accurate, as it provides better definition of the tumor in relation to the surrounding structures. 
• Chest X-ray. At minimum, a chest X-ray should be obtained to determine whether cancer has spread to your lungs. In some instances, a CT scan of the chest and/or PET scan may be useful.  

Ultimately, your doctor will need to take a tissue sample (biopsy) to confirm diagnosis. After numbing the area that will be biopsied, the surgeon will remove a small piece of tissue. He or she will send the sample to a pathologist for examination under a microscope for identification. This information is essential to determine the best treatment plan.

Tumor staging

Staging refers to the size and spread of your cancer: Mount Sinai conducts staging to determine the most appropriate treatment for your particular situation.

T categories for maxillary sinus cancer

T1: Tumor is only in the tissue lining the sinus and has not spread to the bone.

T2: Tumor has begun to grow into some of the bones of your sinus. If the cancer has grown into the bone at the back of your sinus, it is classified as T3.

T3: Tumor has begun to grow into the bone at the back of your sinus or into the ethmoid sinus, between the eye sockets and the nose.

T4a: Tumor has grown into other structures, such as the skin of the cheek, the front part of the eye socket, the bone at the top of the nose, or certain parts of the face. This is also known as moderately advanced local disease.

T4b: Tumor has grown into the area between the nasal cavity and the throat (the nasopharynx), the back of the eye socket, the brain, the tissue covering the brain, some parts of the skull, or certain nerves. This is known as very advanced local disease.

T categories for nasal cancer and ethmoid sinus cancer

T1: Tumor is only in the nasal cavity or one of the ethmoid sinuses, between the eye sockets and the nose, although it may have grown into the sinus bones.

T2: Tumor has grown into other nasal or paranasal cavities

T3: Tumor has grown into bone of the eye socket, the roof of your mouth, the bone that separates your nose from your brain, and/or the maxillary sinus

T4a: Tumor has grown into other structures, such as the front part of your eye socket, the skin of your nose or cheek, the frontal sinus, or certain bones in your face. This is known as moderately advanced local disease. Cancers that areT4a can be surgically removed.

T4b: Tumor has grown into the back of your eye socket, your brain, the tissue covering your brain, some parts of your skull, certain nerves, underneath your skin or eye socket, or between your nasal cavity and your throat. This is known as very advanced local disease. Tumors are called T4b when they cannot be surgically removed.

N categories

N0: No cancer spread (metastasis) to lymph nodes.

N1: Cancer has spread to a single lymph node that is on the same side as the tumor and is no more than 3 cm (slightly larger than one inch).

N2: Cancer has spread to a lymph node that is more than 3 cm (slightly larger than one inch) but is less than 6 centimeters (slightly larger than 2 inches); or cancer has spread to more than one lymph node smaller than 6 cm; or cancer is in a lymph node not on the same side as the tumor (and the lymph node is smaller than 6 cm).

N3: Cancer has spread to at least one nearby lymph node that is larger than 6 cm (slightly larger than 2 inches)

M categories

M0: No cancer spread (metastasis) to distant organs or tissues

M1: The cancer has spread to distant organs, such as your lung, brain, or liver.