People with esophageal cancer may have questions about their prognosis and survival. Prognosis and survival depend on many factors. Only a doctor familiar with a person's medical history, type of cancer, stage, characteristics of the cancer, treatments chosen and response to treatment can put all of this information together with survival statistics to arrive at a prognosis.
A prognosis is the doctor's best estimate of how cancer will affect a person, and how it will respond to treatment. A prognostic factor is an aspect of the cancer or a characteristic of the person that the doctor will consider when making a prognosis. A predictive factor influences how a cancer will respond to a certain treatment. Prognostic and predictive factors are often discussed together and they both play a part in deciding on a treatment plan and a prognosis.
The following are prognostic factors for esophageal cancer.
The most reliable prognostic factor for esophageal cancer is the stage of the tumour at the time of diagnosis. As with most cancers, the lower the stage of esophageal cancer, the better the outcome. Tumours that are only in the lining of the esophagus have a more favourable prognosis than those that have grown through the muscle wall or that have spread to other organs.
Lymph node involvement
Lymph node involvement is related to the stage of the tumour and is an important prognostic factor. The fewer lymph nodes that the cancer has spread to, the better the prognosis.
Smaller tumour size is a more favourable prognostic factor than large tumour size.
The amount of residual tumour that remains after surgery (R classification) is a prognostic factor for esophageal cancer. The prognosis is more favourable if there is no remaining disease after surgery (R0) than if there is microscopic residual disease (R1) or macroscopic residual disease (R2).
Lymphatic vessel involvement
Cancer that has spread to the lymphatic vessels has a less favourable prognosis than cancer that has not spread to the lymphatic vessels.
Cancer that responds to neoadjuvant therapy
Esophageal cancer that responds to neoadjuvant therapy has a better prognosis than cancer that does not respond to neoadjuvant therapy. Cancer that responds to neoadjuvant therapy is more likely to be completely removed by surgery.
Some surgical complications can cause a person with esophageal cancer to have a less favourable prognosis. Surgical complications include:
- anastomotic leak
- leakage at the site where structures are joined together
- vocal cord paralysis
- leakage of chyle (a fat-containing fluid that is taken up from the small intestine into the lymph vessels during digestion) into the space between the pleural membranes that cover the lungs and line the chest cavity
- caused by injury to the thoracic duct (a major lymph vessel)
When an esophageal tumour is removed, the surgeon will take a margin of healthy tissue around the tumour. Margins that are clear of cancer cells suggest a better prognosis than margins that have cancer cells in them.
A low-grade or well-differentiated tumour (G1) often grows slower and is less likely to spread than a high-grade tumour (G3 or G4).
People with a high performance status (Karnofsky score of 70 or greater) have a more favourable prognosis than those with a lower performance status.