Neuroendocrine Tumors

Gregory J. Nadolski, MD, MSc

Michael C. Soulen, MD, FSIR, FCIRSE

The first patient I chemoembolized when I started my career at Penn in 1991 had a neuroendocrine tumor (NET). I went on to embolize him another 14 times over the next two decades, and he lived for 25 years with his disease.

NETs are the second most prevalent gastrointestinal malignancy after colon cancer, outnumbering all other gastrointestinal primaries combined, and the incidence is steadily increasing worldwide. The vast majority of NET patients develop liver metastases, which are the foremost cause of death in this population. Interventional oncologists have played a role in managing this most lethal manifestation of NETs for the past 50 years, primarily through various forms of embolotherapy.

Until recently there were a few other options for treatment of metastatic NETs. The past few years have seen an explosion of positive trials of new systemic agents, which has radically reshaped the landscape of NET therapy. Given the rare incidence of the disease, it is poorly understood in the broader oncologic community. Patients tend to cluster at high-volume centers of excellence. NETs are usually slow-growing tumors; we often remind patients that the trajectory of their disease is a marathon, not a race. There are only so many bullets in our armamentarium. Parsing out therapies in the optimal sequence is critical for maintaining these patients over what may be decades of treatment. It is essential for interventional oncologists to be educated about the range of treatment options, and to participate actively in multidisciplinary care teams to optimally integrate image-guided therapies with surgical and systemic treatments to achieve the best long-term outcomes.

In this issue of Digestive Disease Interventions, experts in surgical, medical, and nuclear oncology summarize the current state of the art in NET therapies, complementing articles on imaging and image-guided interventions. We hope you find this both useful and stimulating to involve yourself in the care of this complex yet rewarding disease.