Are carcinoid tumors benign?

No: Carcinoid tumors are not benign. They are typically (but not always) slower growing than other tumors. They can spread if not found and therefore should be removed.

No: Carcinoid tumors can spread like any other cancer. Symptoms are usually related to the substances produced by the tumor making it into the circulation.

Confusing: Carcinoid tumors are classified as typical or atypical depending on what they look like under the microscope and how this relates to how they behave clinically. Typical carcinoids are most often very slow growing and patients can live to die of other things. Atypical carcinoids will have a less predictable biology and are more likely to require treatment.