Common References to Understand Different Bone Cancer Stages

The process of analyzing the severity of cancer is called staging. Various tests are conducted to reach to a conclusion to know the extent of cancer in the body. There are few popular methods to confirm cancer stages but the most common staging system for bone cancer is the TNM system. This is most widely used cancer staging system. Most hospitals and medical centers use the TNM system as their main method for cancer reporting normally mentioned in the pathology statement.

However no single system method can be used for all different types of cancer diseases. This is mainly due to uniqueness of each cancer type and varied health condition of the patients. Some of the cancers with different staging systems include brain and spinal cord tumors and blood cancers.

The International Union Against Cancer (UICC) uses the TNM system to describe the extent of many solid tumour cancers. These staging guidelines were developed by the American Joint Committee on Cancer (AJCC). TNM stands for tumour, nodes and metastasis.

Bone cancer stages are based on the following categories:

(T)		Describes the size of the primary bone tumor
	TX	Primary (main) tumor cannot be assessed due to lack of information
	T0	No evidence of primary tumour
	T1	Tumour is 8 cm or less in size
	T2	Tumour is larger than 8 cm in size
	T3	Tumour is in more than one place on the same bone (called skip metastases)

 

(N)		Describes that cancer has spread to nearby lymph nodes. It specifies that bone cancer cells have spread to regional lymph nodes.
	NX	Regional lymph nodes cannot be assessed due to lack of information
	N0	No regional lymph node metastasis
	N1	Regional lymph node metastasis

 

(M)		Distant metastasis. This means that cancer has spread to distant  areas of the body
	M0	No distant metastasis
	M1	Distant metastasis
	M1a	Spread to the lung only
	M1b	Spread to other distant sites