Cancer is most simply described as the uncontrolled division of cells which are not normal in a certain part of the body which later on increases in size and then spreads to various other parts of the body by a process called as Metastasis. A localized tumor or lesion is easy to treat compared to one which has undergone metastasis and involved other parts of the body.
In a localized tumor where there is well differentiated extension of tumor the complete excision along with the affected cells can be used as a treatment plan but in case of an invasive lesion where differentiation from the normal cells is poor treatment can be difficult as we cannot remove complete lesion as some cells might be left out and start a new tumor again. In this case Chemotherapy and other treatment procedures are used to aid in the treatment procedure.
In Oral Cavity Squamous Cell carcinoma of the Buccal cheek is the most common and the most pathological is Carcinoma of Tongue as it has very high amount of Blood Supply.
Most commonly Metastasis is the main cause of Death as it is the reason for spreading Cancer or affected neoplastic cells to other parts of the body. Metastasis is of 2 types
- Hematogenous Spread – Through Blood
- Lymphatic Spread – Through Lymph Nodes
Staging of Cancer:
TMN system is the most widely used Universal way of differentiating Cancer Stages. TNM system is based on the
T: Extent of the tumor
M: The presence of distant metastasis of Cancer cells to different parts of the body from the primary site
N: The extent of spread of Cancer cells to the lymph node
- TX: Primary tumor cannot be evaluated
- T0: No evidence of primary tumor
- Tis: Carcinoma in situ (CIS; abnormal cells are present but have not spread to neighboring tissue; although not cancer, CIS may become cancer and is sometimes called preinvasive cancer)
- T1, T2, T3, T4: Size and/or extent of the primary tumor
Regional Lymph Nodes (N)
- NX: Regional lymph nodes cannot be evaluated
- N0: No regional lymph node involvement
- N1, N2, N3: Involvement of regional lymph nodes (number of lymph nodes and/or extent of spread)
Distant Metastasis (M)
- MX: Distant metastasis cannot be evaluated
- M0: No distant metastasis
- M1: Distant metastasis is present
Stages of Cancer based on TNM classification of Cancer:
All the types of Cancers are classified based on types of TNM.
- Stage I: T1, N0, M0
- Stage II: T2, N0, M0
- Stage IIIA: T3a, N0, M0
- Stage IIIB: T3b, N0, M0
- Stage IIIC: T4, N0, M0
- Stage IVA: Any T, N1, M0
- Stage IVB: Any T, Any N, M1