When a gastrointestinal tumor is detected, defining the risk of malignancy and the potential for metastasis, and deciding how to proceed with treatment are issues of immediate concern to both the physician and the patient.
“Often, tumors are found when patients have endoscopic evaluation for problems such as longstanding heartburn or iron deficiency anemia. The lesions may be asymptomatic, but progression can occur,” says Charles Dye, M.D., gastroenterologist from Penn State Hershey Gastroenterology and Hepatology. Dr. Dye explains, “Malignant tumors, such as gastrointestinal stromal tumors [GISTs], also look similar to nonmalignant growths, such as Schwannomas or leiomyomas.”
While tumor size and location can be indicators of a tumor’s malignant potential, pairing endoscopic ultrasound (EUS) with a biopsy technique may allow major surgery to be avoided. Benign tumors can be left in place, while malignant tumors can be staged and risk-stratified to allow the best and most minimally invasive treatment approach. While immediate cytological analysis yields important information about tumor type, ancillary analyses, such as immunohistochemistry and tumor cell mitotic rate, may take several days to complete.
In 2009, Dr. Dye and his colleagues began to collaborate with cytopathologists, performing lesion aspiration and cellular analysis during an EUS procedure (e.g., immediate on-site evaluation), to improve diagnostic success. Because some gastrointestinal tumors, particularly GISTs, are highly fibrous in nature, and fine needle aspiration (FNA) may yield little tissue, Dr. Dye has led research to examine the usefulness of EUS-guided fine needle tissue biopsy (EUS-FNTB).
“With EUS-FNTB, we’ve had greater ease of tissue sampling and diagnostic success with a high pressure suction technique, compared with a quick core device,” he said.
Dr. Dye and colleagues recently described the diagnostic yield of the EUS-guided FNTB procedure in a series of twenty-four patients; about 20 percent of the suspected GISTS were benign Schwannomas or leiomyomas.
Adds Dr. Dye, “By adding effective FNTB techniques to our approach, we’ve developed a high level of expertise in rapidly defining the type of tumor we’re dealing with, while the patient is still under sedation during the procedure. With an experienced cytopathologist onsite to analyze FNA specimens and these newer biopsy techniques, we’re able to provide quick and reliable diagnosis and pre-surgical information in a single procedure.”
|Charles E. Dye, M.D.
Associate Professor of Medicine; Medical Director, Endoscopy Center
FELLOWSHIPS: Therapeutic Endoscopy and Gastroenterology, University of Chicago Medical Center
RESIDENCY: Internal Medicine, University of Chicago Medical Center
MEDICAL SCHOOL: Penn State College of Medicine