GIST Specialist for La Canada Flintridge, CA
Patients with a gastrointestinal stromal tumor accumulate scans quickly and are rarely told what each one is for. Every study answers a different question, and the surgical plan depends on the right ones having been done. Joshua Ellenhorn, MD, FACS reviews them himself.
- Imaging reviewed directly rather than from a report
- Clinical Professor of Surgery, Cedars-Sinai Medical Center
- Clear about which studies are needed and which are not
- Thirty to thirty five minutes via the 210 and 134
Why More Scans Is Not the Same as Better Information
A patient being worked up for a gastrointestinal stromal tumor can easily end up with an endoscopy, an endoscopic ultrasound, a CT, sometimes an MRI, and occasionally a PET, without ever being told what each was for or which one the operation actually depends on.
The distinctions are simple enough. An endoscopy sees the inner surface, and because GIST grows within the wall it will show only a smooth bulge under normal looking lining. Endoscopic ultrasound looks into the wall itself, establishing which layers are involved and allowing controlled tissue sampling. A contrast CT is what defines the tumor in relation to everything around it and looks at the liver, which is where GIST spreads. MRI earns its place in the pelvis, where the distance between a rectal tumor and the sphincter decides the operation, and for characterising ambiguous liver lesions. PET measures activity rather than structure, which makes it valuable for detecting early response to a drug and largely unnecessary for initial staging.
What matters practically is that the study driving the surgical decision is usually the CT, and it is the one most often reviewed as a report rather than as images. Whether a duodenal tumor abuts the pancreas or merely lies near it, whether a rectal tumor sits one centimetre or three from the sphincter: those measurements exist in the images and not in the text.
The Imaging Used in GIST, and What It Answers
Use this to understand what you have already had and what may still be missing.
| Study | What it shows | When it is needed |
|---|---|---|
| Upper endoscopy | The inner surface. A GIST appears as a smooth bulge beneath intact lining | Usually the first test. Confirms something is there but says little about what can be done |
| Endoscopic ultrasound | Depth within the wall, which layers are involved, and allows controlled sampling | When the diagnosis needs confirming or tissue is required before medication |
| Contrast CT of abdomen and pelvis | Size, exact location, relationship to adjacent organs, and liver or peritoneal disease | The core study. Drives the surgical plan and is used for most response assessment |
| MRI | Superior soft tissue detail in the pelvis, and characterisation of ambiguous liver lesions | Rectal tumors, where distance to the sphincter decides the operation, and unclear liver findings |
| PET or PET/CT | Metabolic activity rather than structure | Early assessment of drug response, and clarifying whether an ambiguous lesion is active |
| Capsule endoscopy or enteroscopy | The small bowel lining, beyond the reach of standard scopes | Unexplained bleeding where upper endoscopy and colonoscopy were both normal |
| Diagnostic laparoscopy | Direct inspection of the peritoneal surfaces | When small volume peritoneal disease is suspected and imaging cannot exclude it |
Repeated CT over years of surveillance carries a cumulative radiation consideration, which is one reason schedules should have defined intervals and a stated endpoint rather than continuing indefinitely.
A Scan Read Alone Tells You Less Than You Think
Two things make GIST imaging genuinely different from most cancer imaging, and both are easy to get wrong.
The first is that response is not measured by size alone. A GIST responding to targeted therapy frequently changes density before it changes diameter, becoming less dense while barely shrinking. Assessed by size criteria that reads as stable disease when it is actually a good response. Occasionally a responding tumor bleeds internally and enlarges, which reads as progression and is not. Criteria that account for density exist precisely because of this.
The second is comparison. Liver deposits that started out the same density as surrounding liver are effectively invisible, then become visible as they respond and lose density, which appears on a report as new lesions. They are not new. Establishing that requires the earlier study, which is why keeping your own copies of prior imaging is worth the administrative effort and why a scan read without the previous ones alongside it is a weaker document than it appears.
What the Imaging Makes Possible
Recordings of real GIST resections narrated by the surgeon who performed them. Operations this contained are planned from imaging before the first incision.
Laparoscopic Resection of a Gastric GIST
A gastric GIST removed through small incisions with the capsule kept intact.
Gastric GIST Resection: A Simplified Approach
A refined approach that shortens operating time and recovery.
Robotic Resection of a Duodenal GIST
Duodenal GIST removed robotically with the pancreas and bile duct preserved, a decision made from the CT rather than discovered in theatre.
Images, Not Just the Report
Ask your imaging department for the study itself on disc, USB or portal download. The measurements a surgical plan depends on are in the images and absent from the written summary.
Certifications and Appointments
Two American Board of Surgery certifications, a Cedars-Sinai teaching appointment, and membership of the societies that publish the imaging and response criteria for this disease.
- American Board of Surgery, certified in General Surgery
- American Board of Surgery, certified in Colorectal Surgery
- California State Medical License
- Florida State Medical License
Joshua Ellenhorn, MD, FACS
Dr. Ellenhorn is a surgical oncologist and Clinical Professor of Surgery at Cedars-Sinai Medical Center, and a collaborative member of the Samuel Oschin Comprehensive Cancer Institute.
He reviews the imaging himself rather than working from the radiology report, and for this tumor that is not a formality. The decisions that determine how large your operation is, whether the pancreas or the sphincter or most of the stomach can be preserved, turn on millimetres of anatomical relationship. A report answers the question the radiologist was asked. The surgical question is frequently a different one, and it is answerable only by looking.
He is certified by the American Board of Surgery in General Surgery and in Colorectal Surgery, a Fellow of the American College of Surgeons, and a member of the Society of Surgical Oncology and the American Society of Clinical Oncology. He practises with the Surgery Group of Los Angeles.
What Patients Say
Reviews left by patients treated by Dr. Ellenhorn at the Surgery Group of Los Angeles.
★★★★★The staff at the Surgery Group of Los Angeles are wonderful. They are kind, very attentive, the office is clean and I did not have to wait long at all. I cannot say enough great things about Dr. Ellenhorn. He is an excellent surgeon who is highly skilled and very knowledgeable. I cannot thank him enough for all he has done for my family and I.
Erika Frank
★★★★★Very kind stuff, great service. Dr Joshua Ellenhorn is a very calm doctor who takes time with his patient.
Anita Lukacevic
From La Canada Flintridge
The 210 west to the 134, then the 101 south through the Cahuenga Pass and Highland down to 3rd Street. The 2 south to the 101 is the alternative and can be quicker from the eastern end. Thirty to thirty five minutes outside peak, longer through the pass in the evening.
The office is in the medical plaza attached to Cedars-Sinai Medical Center, where the imaging department and reporting radiologists are in the same building as the surgical consultation. For the subject of this page that is the practical point: studies can be reviewed alongside prior imaging and discussed directly rather than through correspondence.
Patients travelling from outside the region, including Arizona and Nevada, can have imaging reviewed remotely.
8635 W 3rd St, Suite 880W
Los Angeles, CA 90048
Monday to Saturday, 11:00am to 8:00pm
Closed Sunday
Frequently Asked Questions
Why do I need a CT when I have already had an endoscopy?
What does endoscopic ultrasound add?
When is MRI used instead of CT?
What is a PET scan for?
Do I need a PET scan for staging?
Should I worry about radiation from repeated scans?
Why does keeping my old scans matter?
How far is your office from La Canada Flintridge?
The Right Scan Matters More Than More Scans.
A contrast CT drives the surgical plan, EUS establishes depth, MRI settles the pelvis, and PET measures response. Bring the images rather than the reports and the plan can be specific.
