Video
For High-Definition, Click
The staging of a patient with medullary thyroid cancer (MTC) is generally performed during the initial diagnosis. The first step in this process is to check both calcitonin and CEA levels, explains Eric J. Sherman, MD. Following this procedure, imaging of the neck, chest, and liver should be performed to assess tumor size and for the presence of metastases. In general, the type of imaging utilized depends on the CEA and calcitonin levels but in many situations a PET-CT scan is not required, Eric Sherman believes.
In general, calcitonin and CEA are the primary biomarkers in MTC, notes Steven I. Sherman, MD. As patients are followed over time, these markers will change proportionately. As a result, it is important to follow both levels, as a way of verifying the accuracy of testing, believes R. Michael Tuttle, MD. This is further enhanced by inconsistencies in calcitonin assays.
Once calcitonin and CEA levels are assessed, they can be utilized to customize imaging. If both levels are high, Lori J. Wirth, MD believes that performing a PET-CT scan of the neck and chest and an MRI of the liver may help characterize the overall disease burden. Research has suggested, Tuttle adds, that patients with a calcitonin level in the multi-thousands may benefit from a conglomeration of tests, including CT scans of the liver and an MRI of the spine.
In general, bone scans are ineffective for detecting bone metastases in patients with MTC, Steven Sherman notes. Instead, contrast enhanced tomographic imaging is required, to detect the often hypervascular tiny lesions that represent early metastases. As a result, MRI of the spine and pelvis should both be standard procedures, Steven Sherman believes.