Some carcinoid tumors can be slow-growing, but those that grow quickly can spread to other parts of the body. They are often classified by the tumor grade. Grades 1 and 2 are slow growing but can spread. Grade 3 carcinoid tumors grow and multiply faster.
A lot of imaging modalities have been employed in carcinoid tumor detection, including CT and MRI imaging. The techniques work better in combination, especially when identifying the location and metastasis of the carcinoid tumors.
A study was conducted to determine how PET-CT would work in mediastinal lymph node staging of the pulmonary carcinoid tumors. Although it had low sensitivity, PET-CT showed better specificity in detecting mediastinal lymph node metastasis in the pulmonary carcinoid tumors and could be used to guide biopsy.
Computed tomography (CT) and magnetic resonance imaging play a significant role in carcinoid tumors’ workup.
The two imaging techniques help in;
- Diagnosing chest tumors. CT can be combined with scintigraphy with octreotide.
- Detecting liver metastasis and mesenteric invasions. MRI and CT can also help diagnose hepatic disease, especially in detecting extrahepatic lesions.
- Imaging small-bowel carcinoids.
A CT scan often looks to see if a carcinoid tumor has spread to the surrounding lymph nodes or the other organs like the liver. Doctors use it to guide the biopsy needle into areas of concern. In one study, CT scanning helped detect 82% of localized carcinoid tumors compared to the 78% from the other modality.
An MRI scan can demonstrate the findings in carcinoid tumors, including mesenteric metastases, primary tumor, and liver metastases. Most liver metastases are hypervascular and can only be demonstrated on immediate postgadolinium images. MRIs can see a tumor that has spread to the liver. Using MR angiography, doctors can effectively look at the blood vessels in the liver.