Neuroendocrine Tumors: Targeted Therapies - Episode 3
Standard treatment pathways for patients with neuroendocrine tumors involving systemic therapy, surgery, and radiation.
Diane Reidy-Lagunes, MD: Thankfully in the last decade, the treatment landscape for neuroendocrine cancers has actually changed a lot. We offer many more opportunities for our patients who are fighting these diseases. The most important thing I always share with my patients and my fellows is that it’s always about quality and quantity. In many of our patients, for example, with low-grade, low-volume, asymptomatic tumors, we could actually watch them. I have patients for years who I just see once or twice a year, and their cancer is totally stable. They’re totally asymptomatic, and this is a cancer that allows us to watch those types of patients. You want to be very careful though that those are patients without symptoms, typically low-grade and very low-volume disease that can’t be easily resected by surgery.
We have 3 reasons for which we want to decide to start treatment. One is that the cancer is growing under observation. The second is the tumors themselves have high burden of disease, so there’s a lot of disease on imaging. The third is that they’re symptomatic. Whether the tumors themselves, because they’re high burden are causing symptoms, or whether they’re making hormones or are functional tumors, those are the 3 reasons why we decide we want to start treatment. Disease growth under observation, functional or symptomatic tumors, and high burden of disease. The first line of therapy, which I call my “first string” players, are generally somatostatin analogues. That’s either lanreotide or octreotide, and I call them my “first string” players because they’re really good at putting the brakes on the tumor and stopping it from growing and spreading with very mild adverse effects. It’s a shot in the bottom once a month. It’s a hormone as opposed to chemotherapy. The adverse event profile is very well tolerated compared to other cancers.
Once the tumor progresses on somatostatin analogue therapies though, it gets much trickier because unfortunately, we don’t have large, randomized trials to tell us what sequencing therapies are best, what to give in the second line, what to give in the third line. Given the heterogeneity of the disease and given the more uncommon nature of this cancer, we just don’t have those studies that help us guide therapies. This is where it becomes very important to know your patient, know their burden of disease, know the location of the disease, and where that cancer might be growing. Second-line therapies can often, for example if it’s growing in the liver, be liver-directed therapies. If it’s growing outside of the liver, it could be other systemic types of treatments and even if it’s in the liver. There are lots of different variables we use in the second-line setting to better understand what’s the right treatment option for that patient in front of us.
The role of surgery and other modalities such as radiation therapy are important. In any patient with localized disease, if it can surgically be removed in a safe way, we really encourage our patients to have that surgery. Primary tumors, for example, of the small bowel, which is very common, can and often will obstruct if we get into trouble leaving them there. In a localized setting, we always want to surgically remove it if deemed safe to do so. Traditional radiation, which is that beam where patients come in and they get their fraction of radiation every day for a certain period of time, is often used, for example, for palliation of symptoms. For anyone with bone metastasis, the role of radiation can be very important in preventing that tumor from spreading and causing trouble in the bone and preventing pain. We have other types of radiation, such as systemic radiation, which is 177Lu-DOTATATE, as another potential very important treatment option for our patients with neuroendocrine cancer.
Transcript Edited for Clarity