Expert Oncologist Breaks Down the Current Treatment Landscape of GIST

Dr. Rosario Ligresti discussed common signs and symptoms of GIST, as well as highlighted how the treatment landscape has changed.

The treatment of gastrointestinal stromal tumors (GIST) is continuing to evolve with the help of precision-guided therapy and novel therapeutics, according to Dr. Rosario Ligresti, the chief of Gastroenterology and Interventional Endoscopy at Hackensack Meridian Health.

“Among all the gastrointestinal tumors out there, I think [GIST] is probably [most] emblematic of the way oncology is going,” he explained in an interview with CURE.

In the interview, Ligresti sat down to delve into the topic of GIST, and what a diagnosis of this rare cancer entails. He discussed how GIST differs from other types of cancer and common signs and symptoms of the disease, as well as highlighted how the treatment landscape has changed in recent years.

CURE: What exactly is GIST? How does it differ from other types of cancers patients might have heard of?

Ligresti: It's not a common tumor, but it's common enough that [we can find them, and] patients will find it if they get an endoscopy. Oftentimes, the first question patients ask is whether the tumor that the doctor found, which was considered a GIST, is malignant. That's really where things get [tricky] because GISTs fall into a kind of a weird place on the neoplastic or cancer spectrum.

They are not common tumors; they are tumors of the supporting structure of the gastrointestinal tract, kind of like the scaffolding. And again, they are, by and large, benign entities, but they certainly have significant malignant potential. So when we see them, and we see them often enough in patients because they are often found as lumps and bumps during an endoscopy, further characterization is definitely warranted.

As a whole, GISTs are a small percentage of all gastrointestinal neoplasms, probably only 1% to 2% percent of all GI tumors, and there are likely only about 6,000 cases reported in the United States every year. So, it's an uncommon tumor, but it's common enough, as I said, in the population that gets endoscopies.

What are the most common symptoms that may indicate GIST before a diagnosis is made?

The majority of GIST, or gastrointestinal stromal tumors, occur based on the tumor's location and size. The most common location for GIST is generally the stomach, where probably about 60% to 65% of the GISTs I see occur. This is likely because the stomach is a very muscular organ to begin with, and these tumors derive from the muscular supporting structure of the GI tract. While they can be located in the small bowel, esophagus or colon, this is far less common.

The location of the tumor drives the symptoms. If the tumors are small, patients often have no symptoms at all, and they are found incidentally. But as they get larger, they can ulcerate, leading to bleeding, or they could cause trouble swallowing if they obstruct things like the esophagus and stomach. They sometimes feel like a mass if someone is feeling their abdomen. So, depending on the location, they can cause anything from anemia to bleeding, to trouble swallowing, to mass-like effects where they can push on things.

Sometimes there are no symptoms whatsoever. In fact, the vast majority are found incidentally because someone is having an endoscopy for another reason, such as reflux. However, if they were to cause symptoms, probably the number one symptom might be anemia or bleeding.

How has the treatment landscape for GIST changed in recent years?

Among all the gastrointestinal tumors out there, I think this is probably emblematic of the way oncology is going. We talk about precision-guided therapy and precision medicine very often in oncology, but the pathological changes that occur in GISTs symbolize that entire field.

GISTs are very unique tumors in that they start and are driven by one of three specific genetic mutations in a patient's genes. When you have one of these mutations, it can cause these tumors to either grow more or less significantly. The way therapy has changed is that when you have these mutations, you can target them with specific medications.

Originally, when GISTs were first described, the only option for patients was surgery, which remains a very important option. You see the tumor, and you remove it. If patients are presenting with obstruction, bleeding, ulceration or trouble swallowing, removing the tumor is still critical.

However, if the tumor has been diagnosed when the patient already has advanced disease or if it has spread outside of the intestinal tract, that's when you start talking about giving patients medical therapy or chemotherapy. The chemotherapy used for these patients is very different from the standard chemotherapy for other intestinal tumors, such as adenocarcinomas, colon cancers or stomach cancers. These are medications used specifically to block a certain genetic product that these tumors make because of genetic mutations within the tumor.

Reference

1. “The Characterization of GIST: What Patients Should Know,” by Dr. Rosario Ligresti. CURE, Aug. 18, 2025; https://www.curetoday.com/view/the-characterization-of-gist-what-patients-should-know

Transcript has been edited for clarity and conciseness.

For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.