Stages and Grades of esophageal Cancer

Executive Summary

The stages of esophageal cancer helps determine the tumor’s location and metastasis. The staging system of esophageal cancer uses diagnostic tests. A TNM staging system is used to identify the different stages of esophageal cancer. There are other staging systems for the two most common types of esophageal cancer – squamous cell carcinoma and adenocarcinoma. Staging of squamous cell carcinoma includes total of five stages involving stage 0, stage I (IA, IB), stage II (IIA, IIB), stage III (IIIA, IIIB), and stage IV (IVA, IVB). Staging of adenocarcinoma of esophagus includes total of five stages involving stage 0, stage I (IA, IB, IC), stage II (IIA, IIB), stage III (IIIA, IIIB), and stage IV (IVA, IVB). Recurrent is another stage of cancer that comes back after treatment.

Stages of Esophageal Cancer

Staging is the procedure of determining where the tumor is located, whether it has spread or not, and how it grows. While assessing the cancer stage, many factors are taken into account.

Doctors use diagnostic tests to discover cancer’s stage, so staging may not be complete until all tests are finished. 

TNM staging system

The TNM system is the tool doctors use to describe the stage of oesophageal cancer. 

• T is for tumor – How large the tumor is and where is its location
• N is for nodes – Has cancer spread to lymph nodes, and if so, where and how many?
• M is for metastasis – Whether cancer has metastasized to other parts of the body.

Cancer stage grouping

Doctors assign the cancer stage by combining the T, N, and M classifications. There are different staging systems for the two most common types of esophageal cancer- squamous cell carcinoma and adenocarcinoma ^​1​. 

Staging of Squamous Cell Carcinoma of the Oesophagus

For squamous cell carcinoma, the stages can be divided based on whether the tumor is in the upper, middle, or lower part of the esophagus and the grade (G) of the tumor cells ^​2​.

Stage 0 – The cancer is found in only the top lining of the esophagus.

Stage IA – The cancer is in only the top layers of the oesophagus.

Stage IB – Cancer meets either of these conditions –

• Cancer is present in the top layers of the esophagus, and the tumor cells are less differentiated.
• The tumor is present in the third layer of the esophagus, but it has not spread to the lymph nodes or other body parts.

Stage IIA – Meets any of these conditions –

• The tumor is present in the third layer of the esophagus. Cancer cells have spread into but not through the muscle wall of the esophagus.
• The tumor is present in the outer layer of the upper or middle part of the esophagus.
• The tumor is in the outer layer of the lower part of the esophagus.

Stage IIB – Meets of these conditions –

• The tumor is present in the outer layer of the upper or middle part of the esophagus. The tumor cells are less differentiated.
• The tumor is present in the outer layer of any part of the esophagus.
• The tumor is present in any part of the esophagus, and cancer cells have spread into the esophagus lining and underneath layers. Cancer may have spread to 1 or 2 lymph nodes near the tumor.

Stage IIIA – Meets any of these conditions –

• The tumour is present in any part of the oesophagus, and cancer cells have spread into the oesophagus lining and underneath layers. Cancer cells have spread to 3 to 6 lymph nodes near the tumour.
• The tumour is present in any part of the oesophagus and has grown into the third layer of the oesophagus. Cancer cells have spread to 1 or 2 lymph nodes.
• Cancer has spread beyond the oesophagus to nearby tissue but not lymph nodes or other body areas.

Stage IIIB – Meets any of these conditions –

• The tumor is present in any part of the esophagus and has grown into the third layer of the esophagus. It has also spread to 3 to 6 lymph nodes.
• The tumor is present in any part of the esophagus that has grown into the outer layer of the esophagus and to either 1 to 2 or 3 to 6 lymph nodes.
• The tumor is present in any part of the esophagus and has spread to structures surrounding the esophagus. It has either spread to no lymph nodes or only 1 or 2 lymph nodes.

Stage IVA – Meets either of these conditions –

• The tumour is present in any part of the oesophagus and has spread to nearby structures. It may have spread to up to 3 to 6 lymph nodes.
• Cancer has spread to 7 or more regional lymph nodes.

Stage IVB – cancer has spread to other parts of the body.

Staging of adenocarcinoma of the esophagus

Doctors use the T, N, and M classifications and the grade (G) for adenocarcinoma ^​3​.

Stage 0 – The cancer is found in only the top lining of the oesophagus.

Stage IA –  Cancer cells have spread into the lining of the esophagus and the layers underneath.

Stage IB – Cancer meets either of these conditions.

• Cancer has grown into layers underneath the lining of the esophagus. The tumor cells are moderately differentiated.
• Cancer has spread to a layer of the esophagus called the submucosa.

Stage IC – Cancer meets either of these conditions.

• Cancer has grown into layers underneath the esophagus or the submucosa lining. The cancer cells are poorly differentiated.
• Cancer has grown into the third layer of the esophagus. The cancer cells are moderately or well-differentiated.

Stage IIA –  cancer is in the third layer of the esophagus. The grade can’t be evaluated, or the cells are poorly differentiated.

Stage IIB –  Either of these conditions:

• Cancer in the outer layer of the esophagus.
• Cancer in the inner layer of the esophagus has spread to 1 or 2 lymph nodes.

Stage IIIA – Either of these conditions:

• Cancer in the inner layers of the esophagus has spread to 3 to 6 lymph nodes near the tumor.
• Cancer is the third layer of the esophagus and has spread to 1 or 2 lymph nodes.

Stage IIIB –  Any of these conditions –

• Cancer is the third layer of the esophagus and 3 to 6 lymph nodes.
• Cancer in the outer layer of the esophagus has spread to 1 to 2 or 3 to 6 lymph nodes.
• The tumor has spread to structures near the esophagus and either no lymph nodes or 1 or 2 lymph nodes.

Stage IVA – Any of these conditions:

• The tumor has spread to structures near the esophagus and either no lymph nodes or up to 3 to 6 lymph nodes.
• The tumor has spread to 7 or more lymph nodes.

Stage IVB –  cancer has spread to another part of the body.

Recurrent –  Recurrent cancer is cancer that has come back after treatment. The disease can be found in the colon, rectum, or another body part. If cancer returns, there will be another round of tests to know the extent of the recurrence. These tests and scans are usually similar to those at the original diagnosis.

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