The doctor will ask about your medical history and will do a careful physical exam. You most likely will be asked to give blood for hormone measurements, and you may also be asked to have an ultrasound, CT scan or MRI to enable the doctor to determine where the growth is located and whether it has spread.
The only sure way to tell whether cancer is present is with a biopsy. The doctor removes a small sample of tumor tissue, which is examined under a microscope by a pathologist. If cancer cells are found, the pathologist will usually determine the stage or grade of the tumor, which tells whether the cancer is spreading. Based on the biopsy results, your doctor may refer you to a specialist in endocrine cancer.
For some tumors, it is not possible to tell if a tumor is benign or malignant (cancerous) before an operation. In these cases, the only way to know if a tumor is cancer is to examine the entire tumor after surgery, and to see if there is evidence of residual tumors after the main tumor is removed.