A prognosis is a prediction of the outcome of one’s disease. How likely is survival? Will the cancer come back? These are the big questions on most people’s minds after receiving a diagnosis of medullary thyroid cancer. In general, there are several characteristics of the tumor that can inform a patient about their chances of being cured.
Factor That Affect Prognosis
Age
A patient’s age at diagnosis is an important factor in prognosis for MTC. Patients younger than 40-45 have improved survival compared to those that are older.
Stage
This is the most important factor that affects a patient’s chance of being cured.
Site
The location and size of the tumor in the thyroid gland can affect the surgeon’s ability to resect the tumor with adequate margins of healthy tissue around it.
Calcitonin and CEA levels
Higher or rising blood levels of calcitonin or CEA following surgery have been associated with a poorer prognosis
Spread to Lymph Nodes
Spread to lymph nodes in the neck decreases the chance of cure, especially if there is evidence of cancer growth outside of the lymph node.
Vascular Invasion
The presence of vascular invasion in the primary tumor is a poor prognostic feature.
Genetic Mutations
Some specific RET gene mutations are associated with more aggressive medullary thyroid cancers (MEN 2B).
While each of these factors contributes to one’s outcome, patients should have a discussion with their doctor to determine their overall prognosis. Giving a percentage of survival is challenging because cancer research often looks at multiple types of cancer and may include a large range of patients who underwent a variety of treatments.
Prognosis of Medullary Thyroid Cancer
SEER stands for Surveillance, Epidemiology, and End Results Program. The SEER database is a large American cancer database that tracks 5-year relative survival rates for cancer in the United States, based on how far the cancer has spread. Instead of grouping cancers according to AJCC TNM stages (I,II,III,IV), SEER categorizes cancers into localized, regional, and distant stages. The data below is provided according to SEER data:
Survival Rates for Patients with Medullary Thyroid Cancer
| SEER Stage | Estimated Disease-Specific Survival at 5 Years |
| Localized | 99.9% |
| Regional | 91.0% |
| Distant | 37% |
- Localized: There is no sign that the cancer has spread outside of the thyroid.
- Regional: The cancer has spread outside of the thyroid to nearby structures.
- Distant: The cancer has spread to distant parts of the body such as the bones.
Disclaimer: Estimated Disease-Specific Survival is the percentage of people with a specific cancer who are alive at a given time point, such as five years after diagnosis. It excludes people who may have died from a disease other than their cancer. While these estimates from large national databases are helpful, it is important to remember that these broad statistics may not apply to one’s individual situation.
