P31: Accuracy of DOTATATE PET/CT in the Preoperative Planning of Small Bowel Neuroendocrine Tumor Resection

Thursday, March 23, 2023

12:46 PM – 12:51 PM

Location: SSO HUB Pan-Tumor Zone: CRS, HPB, Pan-Tumor & Upper GI

Poster Presenter(s)

Chi Zhang, MD

Resident
Mayo Clinic Arizona
Scottsdale, Arizona, United States

Disclosure information not submitted.

Author(s)

Chi Zhang, MD

Resident
Mayo Clinic Arizona
Scottsdale, Arizona, United States

Disclosure information not submitted.
Hallbera Gudmundsdottir, MD

Resident
Department of Surgery, Mayo Clinic, United States

Disclosure(s): No financial relationships to disclose
AG

Amy E. Glasgow, M.H.A.

Assistant Professor of Health Services Research
Mayo Clinic
Rochester, Minnesota, United States

Disclosure information not submitted.
PS

Patrick Starlinger, MD

Senior Associate Consultant
Division of Hepatobiliary and Pancreas Surgery, Mayo Clinic, United States

Disclosure information not submitted.
Susanne G. Warner, MD

Assistant Professor of Surgery
Mayo Clinic

Disclosure information not submitted.
Travis E. Grotz, MD

Assistant Professor
Mayo Clinic
Rochester, Minnesota, United States

Disclosure(s): No financial relationships to disclose
RS

Rory L. Smoot, MD

Associate Professor of Surgery, Associate Professor of Biochemistry and Molecular Biology
Mayo Clinic, Department of Surgery and Department of Biochemistry and Molecular Biology, United States

Disclosure information not submitted.
Mark J. Truty, MD, MSc

Practice Chair
Mayo Clinic Rochester
Rochester, Minnesota, United States

Disclosure information not submitted.
SC

Sean Cleary, MD

Professor
Division of Hepatobiliary and Pancreas Surgery, Mayo Clinic, United States

Disclosure information not submitted.
DN

David Nagorney, MD

Professor
Division of Hepatobiliary and Pancreas Surgery, Mayo Clinic, United States

Disclosure information not submitted.
MK

Michael Kendrick, MD

Professor
Division of Hepatobiliary and Pancreas Surgery, Mayo Clinic, United States

Disclosure information not submitted.
PN

Patrick Navin, MB BCh

Assistant Professor
Radiology, United States

Disclosure information not submitted.
TH

Thorvardur Halfdanarson, MD

Professor
Medical Oncology, United States

Disclosure information not submitted.
CT

Cornelius A. Thiels, DO, MBA

Assistant Professor
Division of Hepatobiliary and Pancreas Surgery, Mayo Clinic, United States

Disclosure information not submitted.

Disclosure(s):

Hallbera Gudmundsdottir, MD: No financial relationships to disclose

Travis E. Grotz, MD: No financial relationships to disclose

Introduction: Small bowel neuroendocrine tumors (sbNETs) incidence is on the rise. Given that sbNETS are often multifocal with high risk of regional nodal metastasis, open resection with lymphadenectomy is the gold standard approach as it offers manual palpation of the entire small bowel. We evaluated the accuracy of preoperative DOTATATE PET/CT in estimating the number of lesions and the presence of nodal disease compared to postoperative pathology findings. We hypothesize that it may allow for the safe transition to total MIS approaches.

Methods: A multicenter analysis was performed on all patients with biopsy confirmed sbNET who underwent surgery between 1/2016-8/2022 and had preoperative DOTATATE PET/CT. Only patients who underwent open small bowel anastomoses were included. Preoperative imaging reports were compared to the final postoperative pathology reports to determine the predictive power of DOTATATE PET/CT. Descriptive statistics were used.

Results: A total of 104 patients met the inclusion criteria, 56% were female. The median age was 63 (IQR 55,72). On pathology, 53% (n=55) of the patients had multifocal small bowel disease and 79% (n=82) had nodal metastasis. Radiology reports indicated that 27% (n=28) had multifocal sbNETs and 77% (n=80) had nodal disease. DOTATATE PET/CT accurately predicted presence of sbNET lesions 88% of the times (n=92), underpredicted lesions 12% of the times (n=12), and never overpredicted. Sensitivity, specificity, PPV, and NPV were calculated (Table). The presence of lymph node metastases was accurately predicted 69% (n=72) of the times, underpredicted 16% (n=17) of the times, and overpredicted 14% (n=15) of the times (Table).

Conclusions: Although DOTATATE PET/CT has high sensitivity and is relatively accurate, the specificity and NPV is not sufficient to guide surgical planning. Its preoperative use should not be used to replace open palpation to identify additional synchronous lesions or to omit regional lymphoidectomy. This suggests that further research is needed before considering total minimally invasive (robotic) resection with intra-corporeal anastomosis for these patients.

Learning Objectives:

Upon completion, participants will be able to describe the accuracy of DOTATATE PET/CT in identifying multifocal sbNET and lymph node metastases.
Upon completion, participants will be able to understand that preoperative DOTATATE PET/CT cannot replace manual palpation of the small bowel to identify additional synchronous lesions or to omit regional lymphadenectomy.
Upon completion, participants will be able to conclude that current imaging cannot facilitate transition of sbNET surgery to complete robotic resection.