Handheld probe detects radiolabeled gastrinoma tumors intraoperatively

Last Updated: 2015-04-09

By Reuters Staff

NEW YORK (Reuters Health) - A handheld gamma detection probe (HGDP) used in concert with a portable large field of view gamma camera (LFOVGC) allows localization and resection of radiolabeled gastrinomas during surgery for Zollinger-Ellison syndrome (ZES), researchers report.

Gastrinoma tumors associated with ZES are often small, difficult to palpate, multiple in number, and therefore difficult to identify and completely remove during surgery.

Incorporating real-time imaging into the operating room could provide surgeons with intraoperative tumor localization and thereby optimize resection of all possible sites of disease.

Dr. Nathan C. Hall, from Ohio State University, Columbus, and Hospital of the University of Pennsylvania, Philadelphia, and colleagues describe the use of an LFOVGC and an HGDP for identification and complete removal of all sites of disease in five patients with symptomatic ZES.

Three of the five patients had undergone at least one previous gastrinoma-related surgical procedure with curative intent.

The surgeons used the HGDP and LFOVGC intraoperatively to identify and resect 15 lesions in the five patients, according to the April 1 Journal of the American College of Surgeons online report.

Ten of the 15 specimens were positive for neuroendocrine tumor (NET) by surgical pathology and positive for radiolabeled activity with LFOVGC. The other five specimens were pathologically benign and negative for radiolabeled activity.

Three of the 10 NET-positive tumors had not been detected by standard surgical techniques, even with use of the HGDP, and these techniques did not delineate the benign status of the other five specimens.

All patients experienced postoperative declines in gastrin levels and dramatic improvements or resolution of their preoperative symptoms.

After an average of 353 days after surgery (range, 246-751 days), no deaths have occurred and no patients have been lost to follow-up.

"Quality readable imaging can be obtained within five minutes of the start time of image acquisition for the patient scans and one minute for the specimen scans, which is easily viewable to the surgeon on a laptop workstation, providing immediate real-time navigational feedback using the LFOVGC," the researchers note.

"We fully recognize that our current series of cases using both the LFOVGC imaging and the HGDP is limited by its small sample size, and the fact that we are unable to offer any comparison to patients' surgical management using the HGDP alone," the investigators caution. "However, this proof of concept pilot series holds great potential promise in enhancing the long-term surgical outcomes of gastrinoma patients for an otherwise difficult disease to surgically manage."

They conclude, "The real-time intraoperative information provided by the LFOVGC proved to be a useful adjunct tool to supplement the real-time intraoperative navigational localization capabilities provided by the HGDP. We believe this combined approach warrants further investigation, as it has the potential to greatly improve long-term patient outcomes in patients with ZES."

These data were presented at the CARS 2014 Computer Assisted Radiology and Surgery, 28th International Congress and Exhibition, Fukuoka, Japan, June 2014.

Dr. Hall did not respond to a request for comments.

Digirad Corporation provided cameras and technical support for this study. The authors declared no conflicts of interest.

SOURCE: http://bit.ly/1DN1OD6

J Am Coll Surg 2015.