Treatment Strategies in Neuroendocrine Tumors - Episode 2
Jonathan R. Strosberg, MD: The role of surgery in locally advanced disease really depends on which organ we’re talking about and what we mean by locally advanced. If we’re talking about pancreatic neuroendocrine tumors, there are some cases where you have invasion of SMA (superior mesenteric artery), SMV (superior mesenteric vein), or portal vein, where the tumor is initially unresectable but can potentially be shrunk with neoadjuvant treatment—either chemotherapy, by itself, a combination of chemotherapy radiation, or maybe even peptide receptor radiotherapy. So, there are effective ways of shrinking pancreatic neuroendocrine tumors that can eventually lead to surgery.
With small bowel neuroendocrine tumors, we often see presence of multiple lymph nodes—often lymph nodes extending to the root of the mesentery. That’s still technically locally advanced. It really depends on whether those mesenteric lymph nodes involve major vessels, when deciding whether the disease is surgically resectable or not. Even if not all the disease is resectable, sometimes you can remove most of the disease and maybe even try to dissect tumors off the major vessels. However, this can get quite complicated.
The problem is, there aren’t really effective neoadjuvant treatments for that scenario. Mesenteric masses are often highly chemo resistant. There’s a lot of fibrotic tissue in addition to the cancer cells. So, they don’t tend to shrink with somatostatin analogs, chemotherapy, radiation, etc. And so, there are cases where surgery is quite difficult.
Heloisa P. Soares, MD: The role of surgery in metastatic disease is actually very present, and I don’t think anyone should disregard having a cytoreductive surgery in metastatic disease. For instance, if someone has a lot of disease in the liver, there are data that show that debulking up to 80% or 90% of the tumors might be beneficial for patients. It may help with symptom control, if they have a lot of carcinoid syndrome symptoms. There is also the role of resecting mesenteric masses in the setting of metastatic disease. With time, the mesenteric masses can continue to grow and can cause a lot of local problems that may potentially lead to death. So, in situations like that, I think considering surgery is very important, even in the metastatic setting.
Timothy J. Hobday, MD: Surgery has always been a very important part of care for our patients with neuroendocrine tumors. If patients have a localized tumor, we hope that surgery will cure the problem. In that setting, the newer approval of gallium 68 DOTATATE receptor imaging may help us locate small-volume metastatic disease that we didn’t otherwise know about. That may certainly affect the curative potential of surgery, although it may or may not affect whether it’s still a good idea in an individual patient. The reason I say this is we often use surgery as a palliative modality for patients with neuroendocrine tumors. Many times, resection of their primary and regional disease, as well as the vast majority of their metastatic disease, may improve symptoms and quality of life. A lot of historical evidence suggests that it will prolong survival as well. In that situation, novel imaging that detects small-volume metastatic disease that we didn’t otherwise know about, from our traditional cross-sectional imaging, may or may not impact the appropriateness of surgical intervention in those patients, since we know that the goal is prolonging palliation and increasing quality and length of life.
Surgical techniques have been refined. Laparoscopic surgery is more of an option for many of our patients, even those with complex or large pancreatic operations or large liver resections. So, that certainly speeds recovery and, in expert hands, can be a very good option for some patients.
A very important small subset of our patients have significant carcinoid heart disease, which can be function-threatening and, ultimately, life-threatening. There are select centers that have developed surgical expertise in valve replacement and repair for patients with carcinoid heart disease. It greatly improves both their quality of life and survival, in the correct hands, in this very high-risk operation.
Transcript Edited for Clarity