Diagnosis and Staging


Diagnosis and treatment begin with a physical examination that uncovers a suspicious lump or lesion. Following that, the physician or dentist may decide to conduct some tests, including

  • Imaging, which refers to x rays or scan studies that reveal what is inside the head and neck. In the mouth, small lesions might be easily visible and imaging diagnostics might not be necessary. However, if the tumour is deep inside the tissue, additional diagnostic techniques can be used to determine the limits of the tumour and if invasion of the surrounding tissues has occurred.
  • Biopsy, which is a small incision or a needle aspirate (an small injection needle used to aspirate  tissue cells) on the lesion or lump taken to examine the tissues under a microscope and determine if there is cancer and if so, what type it is, and whether the lesion should be followed up with surgery. Biopsies can also be performed with the aid of imaging techniques to pin point the exact location of the tumour and to determine if the lymph nodes are compromised. (Head and Neck Cancer Guide)


Staging refers to a cancer classification system that tells the physician how far along the disease is. The TNM system of the American Joint Committee on Cancer is widely accepted and used across the world. T stands for size of the tumour; N refers to the spread to the lymph nodes; and M means metastasis or spread to distant organs.

T  :  Size of the tumour
T0: No evidence of primary tumour.
Tis: Carcinoma in situ: the cancer has affected the epithelial cells (specialized cells that produce saliva) lining the oral cavity, but the tumour is not deep.     
T1: Tumour is 2 cm (1 cm equals 0.39 inches) or smaller.
T2: Tumour is larger than 2 cm but smaller than 4 cm.
T3: Tumour is larger than 4 cm.
T4: The tumour is any size and has invaded adjacent structures, such as the larynx, bone, connective tissues, or muscles.

N: Lymph node involvement
N0: No metastasis in the regional lymph nodes.
N1: Metastasis in one lymph node on the same side of the primary tumour and smaller than 3 cm.
N2: Divided into 3 subgroups. N2a is metastasis in one lymph node larger than 3 cm and smaller than 6 cm. N2b is metastasis in multiple lymph nodes on the same side of the tumour, none larger than     6cm. N2c denotes one or more lymph nodes, which may or may not be on the side of the primary tumour, none larger than 6 cm.
N3: Metastasis in lymph node larger than 6 cm

M  : Distant metastasis
M0: No distant metastasis.
M1: Distant metastasis present.

Santhanam, Kausalya, and Rebecca J. Frey. “Oral Cancers.” The Gale Encyclopedia of Cancer: A Guide to Cancer and Its Treatments, edited by Kristin Fust, 4th ed., vol. 2, Gale, 2015, pp. 1295-1303. Gale Virtual Reference Library.