Expert oncologist Robert Ramirez, DO, FACP, reflects on the challenges of diagnosing neuroendocrine tumors, which often go overlooked, and discusses his initial thought process for when a patient presents to him with this disease.
PUBLISHED May 14, 2018
Robert Ramirez, DO, FACP: Welcome to the CURE® Expert Connections® on neuroendocrine tumors. I’m Dr. Robert Ramirez. I am a medical oncologist at Ochsner Medical Center in New Orleans, and I am a medical oncologist at the LSU [Louisiana State University] and Ochsner Neuroendocrine Tumor Program in Kenner, Louisiana. Today we’re going to discuss neuroendocrine tumors and will be joined by 2 of our patients who are going to share their stories.
Neuroendocrine tumors are somewhat uncommon. We’re seeing more and more of these tumors, and we’ll talk more about some of the reasons for that. They arise from the diffuse neuroendocrine system and can actually arise from any organ in the body. The majority of time, these things start out in the abdomen: most commonly in the small intestine, but we can see this in the colon and also pancreas. We also can see this above the diaphragm. We actually see this up to 30% of the time starting out in the lung.
They tend to be slow growing, but they can range in degrees of aggressiveness from very, very indolent all the way to very, very aggressive and anywhere between. So treatment for these sorts of tumors depends on where you fall on that spectrum. Now, patients can come in with a variety of symptoms depending on 1) where their tumor starts and 2) whether there are any associated hormonal syndromes. Depending on where things start, it can be a very slow process as far as the first onset of symptoms to an actual diagnosis. Some people will say it’s sometimes up to 10 years between the first recognition of symptoms until the time someone gets diagnosed.
The diagnosis of neuroendocrine tumors varies. It depends on where things are located, where the primary tumor starts, and the associated hormone production. For instance, many times these things will start in the small intestine and cause problems due to excess hormone secretion. Patients may complain of vague abdominal complaints: diarrhea, flushing, or sometimes abdominal pain. This can go on for a very, very long time. Sometimes they seek treatment with a GI [gastrointestinal] doctor, who does the standard treatment and the standard diagnostic tests, including a colonoscopy. Sometimes they get a scan; sometimes they don’t. What I commonly see is that patients get labeled as having irritable bowel syndrome. I saw a patient just earlier this week who was labeled as having Crohn disease and was treated as such for many years until somebody actually got a tissue diagnosis. Now, those are the tumors that start out in the abdomen with these complaints. Sometimes they’re asymptomatic.
Sometimes someone does a scan for another purpose and says, “Oh, there’s something in the liver or in the small intestine.” But I commonly see that for patients who have tumors start out in the lungs, it’s a little bit different. Sometimes they’re asymptomatic and get a scan for another reason, and a physician says, “Oh, you’ve got a nodule or a mass in the lung,” but things can vary. Patients who have tumors that start out in the lungs can have cough and can cough up blood sometimes. It’s a relatively common presentation with shortness of breath and wheezing. Many times, patients get misdiagnosed with asthma and are put on asthma medication for years and years, and then someone finally does a scan and says, “Oh, you’ve got something there.” The timing of a diagnosis can vary from the initial symptoms to an actual correct diagnosis.
When we look at tumors underneath the microscope, we categorize them in 3 different ways. First, we look at the differentiation status, and that tells us how closely this tumor resembles this site of origin. It goes from well differentiated, moderately differentiated, poorly differentiated, to sometimes even undifferentiated. Your well-differentiated cells tend to resemble your tumor of origin or your site of origin, while your poorly differentiated cells don’t. Based on that, we can say where you’re at on the spectrum of aggressiveness. The well-differentiated cells tend to be more indolent than your moderately differentiated cells and your poorly differentiated cells. The other thing that we use is mitotic index. That’s the number of mitoses. When the pathologist looks at this underneath the microscope, it tells us how these cells are dividing. Then there’s something called the Ki 67, which is essentially a percentage of those dividing cells. Being a percentage, it goes anywhere from less than 1% all the way to 100%, with 100% being very, very fast growing and 1% being more on the slow-growing side.