T1A – One vocal cord
T1B – Both vocal cordsT2: Tumour meets at least one of the following criteria:

extends to supra- or sub-glottis
impairs vocal cord mobilityT3: Tumour meets at least one of the following criteria:

causes fixation of the vocal cords
invades the paraglottic space
involves the thyroid cartilage’s inner cortexT4: Same as “Supraglottis”

Subglottis
T1: Tumour is only in the subglottis
T2: Tumour involves both subglottis and vocal cords (regardless of cord mobility)
T3: Same as “Glottis”
T4: Same as “Supraglottis”

N
If Using Clinical (Non-Pathological) Diagnosis
NX: Unable to assess
N0: No involvement of neighbouring lymph nodes
N1: Tumour meets ALL of the following criteria:

involves single lymph node
involved lymph node on the same side of the body as tumour
involved lymph node less than 3 cm in “greatest dimension”
lacks extension beyond the lymph nodeN2: Tumour meets ANY of the following criteria

N2A – Same as N1, except size can be between 3–6 cm
N2B – Same as N2A, except lymph nodes can be  multiple, and there is no minimum size
N2C – Same as N2B, except lymph nodes can be on any side of the bodyN3: Tumour meets ANY of the following criteria:

N3A – Same as N1, except size is greater than 6 cm
N3B – Tumour obviously extends beyond the lymph node border (regardless of number, size, or location of lymph nodes)If Using Pathological Diagnosis
NX: Same as “Clinical Diagnosis – NX”
N0:  Same as “Clinical Diagnosis – N0”
N1:  Same as “Clinical Diagnosis – N1”
N2: Tumour meets ANY of the following criteria

N2A – Same as “Clinical Diagnosis – N2A”, except tumour can extend beyond the involved lymph node
N2B – Same as “Clinical Diagnosis – N2B”
N2C – Same as “Clinical Diagnosis – N2C”N3: Tumour meets ANY of the following criteria:

N3A – Same as “Clinical Diagnosis – N3A”
N3B – Any provable presence of tumour extension beyond the lymph node

M
M0: No evidence of distant metastasis
M1: Evidence of distant metastasis

Treatment
Specific treatment depends on the location, type, and stage of the tumour.
Death from laryngeal cancer is 20 times more likely for the heaviest smokers than for their non-smoking peers. Heavy chronic consumption of alcohol, particularly alcoholic spirits, is also a significant risk factor. When present in combination, the usages of alcohol and tobacco appear to have a synergistic effect. Other reported risk factors include being of low socioeconomic status, male sex, or age greater than 55 years.Occupational exposure to environmental factors such as wood dust, paint fumes, and certain chemicals used in the metalworking, petroleum, plastics, and textile industries is also believed to be a risk factor for laryngeal cancers. Infections by some strains of Papillomaviridae carry some risk of laryngeal carcinoma.People with a history of head and neck cancer are known to be at higher risk (about 25%) of developing a second, separate cancer of the head, neck, or lung. This is likely due to chronic exposure to the carcinogenic effects of alcohol and tobacco. In this situation, a field change effect may occur, where the epithelial tissues start to become diffusely dysplastic with a reduced threshold for malignant change. This risk may be reduced by quitting alcohol and tobacco. Diagnosis
Diagnosis is made by the doctor on the basis of a medical history, physical examination, and special investigations which may include a chest x-ray, CT or MRI scans, and tissue biopsy.