Biomedical Engineering Reference
In-Depth Information
Table 19.1
TNM Classification of Cancer Staging
T—Size of the Primary Tumor
T1
2 cm diameter
T2
2-4 cm diameter
T3
4 cm diameter
T4
Massive, invading other tissues
N—Cervical Nodes
N0
Tumor cells absent from regional lymph nodes
N1
Single node with size
3 cm
N2
Single node with size 3-6 cm (N2a), multiple nodes (N2b), or contralateral
nodes (N2c)
N3
Multiple nodes with size
6 cm
M—Distant Metastasis
M0
Present
M1
Absent
l
maxillectomy (removal of the part of affected bone tissue in maxilla or upper jaw);
l
mandibulectomy (removal of the part of affected bone tissue in mandible or lower jaw);
l
glossectomy (tongue removal, can be total, hemi or partial);
l
radical neck dissection, in which there is removal of lymph nodes and other structures in the head
and neck that are likely or proven to be malignant;
l
laryngectomy, where the part or whole of the larynx is removed if it is affected with cancer;
l
combinational, e.g., glossectomy and laryngectomy done together;
l
photodynamic therapy.
Owing to the vital nature of the structures in the head and neck area, surgery for larger cancers is
technically demanding. Reconstructive surgery may be required to give an acceptable cosmetic and
functional result. Bone grafts and surgical flaps are used to help rebuild the structures removed during
excision of the cancer. An oral prosthesis may also be required. Most oral cancer patients depend on
a feeding tube for their hydration and nutrition. Some will also get a port for the chemotherapy to be
delivered. Many oral cancer patients are disfigured and suffer from many long-term side effects. The
aftereffects often include fatigue, speech problems, trouble maintaining weight, thyroid problems,
difficulty in swallowing, memory loss, weakness, dizziness, high-frequency hearing loss, and sinus
damage.
Survival rates for oral cancer depend on the precise site and the stage of the cancer at diagnosis.
Overall, survival is around 50% at 5 years when all stages of initial diagnosis are considered. Survival
rates for T1-N0 cancers are 90%, hence the emphasis on early detection to increase survival outcome
for patients. For T2/3-N1, it is 30% and worse for T4. Following treatment, rehabilitation may be
necessary to improve movement, chewing, swallowing, and speech. Speech and language pathologists
may be involved at this stage.
