TNM Classification of Oesophageal Cancer

Obviously this rests on the histopathological report obtained. Guidelines exist as to the contents of oesophageal cancer histology reporting.

T descriptor

• Tis. Carcinoma in situ.

• TI. Tumour invades lamina propria, muscularis mucosa or submucosa, but does not extend into the muscularis propria.

• T2. Tumour invades muscularis propria.

• T3. Tumour extends beyond the muscularis propria into the periesophageal tissues.

• T4. Tumour invades adjacent structures.

N descriptor

• NO. No regional lymph-node metastasis.

• NI. Regional lymph-node metastasis.

Regional lymph nodes are difficult to define and depend on the anatomic level of the tumour. Furthermore, attempts at lymph-node mapping (similar to lung cancer) have not been widely adopted for oesophageal cancer. In general, lower thoracic lymph node metastases from a cervical oesophageal tumour are considered distant (M) disease, as are coeliac lymph node metastases from a lower-third oesophageal carcinoma.

M descriptor

• No distant metastases.

• Distant metastases.

For tumours of lower thoracic oesophagus:

• Mla. Metastasis in coeliac lymph nodes.

• M lb. Other distant metastasis.

For tumours of mid-thoracic oesophagus:

• Mia. Not applicable.

• Mib. Nonregional lymph node or other distant metastasis.

For tumours of upper thoracic oesophagus:

• Mia. Metastasis in cervical lymph nodes.

• Ml b. Other distant metastasis.

TNM subsets for the stages of oesophageal cancer