Resection Versus Observation of Small Asymptomatic Nonfunctioning Pancreatic Neuroendocrine Tumors

  • Alex Barenboim
  • Guy Lahat
  • Ido Nachmany
  • Richard Nakache
  • Yaakov Goykhman
  • Ravit Geva
  • Ester Osher
  • Erez Scapa
  • Ido Wolf
  • Lior Orbach
  • Eli Brazowski
  • Ofer Isakov
  • Joseph M. Klausner
  • Nir LubezkyEmail author
Original Article



Management of asymptomatic, nonfunctioning small pancreatic neuroendocrine tumors (PNETs) is controversial because of their overall good prognosis, and the morbidity and mortality associated with pancreatic surgery. Our aim was to compare the outcomes of resection with expectant management of patients with small asymptomatic PNETs.


Retrospective review of patients with nonfunctioning asymptomatic PNETs < 2 cm that underwent resection or expectant management at the Tel-Aviv Medical Center between 2001 and 2018.


Forty-four patients with small asymptomatic, biopsy-proven low-grade PNETs with a KI67 proliferative index < 3% were observed for a mean of 52.48 months. Gallium67DOTATOC-PET scan was completed in 32 patients and demonstrated uptake in the pancreatic tumor in 25 (78%). No patient developed systemic metastases. Two patients underwent resection due to tumor growth, and true tumor enlargement was evidenced in final pathology in one of them. Fifty-five patients underwent immediate resection. Significant complications (Clavien–Dindo grade ≥ 3) developed in 10 patients (18%), mostly due to pancreatic leak, and led to one mortality (1.8%). Pathological evaluation revealed lymphovascular invasion in 1 patient, lymph node metastases in none, and a Ki67 index ≥ 3% in 5. No case of tumor recurrence was diagnosed after mean follow-up of 52.8 months.


No patients with asymptomatic low-grade small PNETs treated by expectant management were diagnosed with regional or systemic metastases after a 52.8-month follow-up. Local tumor progression rate was 2.1%. Surgery has excellent long-term outcomes, but it harbors significant morbidity and mortality. Observation can be considered for selected patients with asymptomatic, small, low grade PNETs.


Neuronedocrine tumors Obervation Pancreatic resection 


Author’s Contribution

Study concepts: Barenboim, Lubezky, Scapa, Osher, Geva, Nakache, Goykhman, Nachmany, Wolf, and Klausner

Study design: Barenboim, Lubezky, Scapa, Osher, Geva, Nakache, Goykhman, Nachmany, Wolf, and Klausner

Data acquisition: Barenboim, Lubezky, Orbach, Scapa, Osher, Geva, Nakache, Goykhman, Nachmany, Wolf, and Klausner

Quality control of data: Barenboim, Lubezky, Scapa, Osher, Geva, Nakache, Goykhman, Nachmany, Wolf, and Klausner

Data analysis and interpretation: Barenboim, Lubezky, Brazowski, Scapa, Osher, Geva, Nakache, Goykhman, Nachmany, Wolf, and Klausner

Statistical analysis: Isakov

Manuscript preparation: Barenboim, Lubezky, Scapa, Osher, Geva, Nakache, Goykhman, Nachmany, Wolf, and Klausner

Manuscript editing: Barenboim, Lubezky, Scapa, Osher, Geva, Nakache, Goykhman, Nachmany, Wolf, and Klausner

Manuscript review: Barenboim, Lubezky, Scapa, Osher, Geva, Nakache, Goykhman, Nachmany, Wolf, and Klausner.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.


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Copyright information

© The Society for Surgery of the Alimentary Tract 2019

Authors and Affiliations

  • Alex Barenboim
    • 1
  • Guy Lahat
    • 1
  • Ido Nachmany
    • 1
  • Richard Nakache
    • 1
  • Yaakov Goykhman
    • 1
  • Ravit Geva
    • 2
  • Ester Osher
    • 3
  • Erez Scapa
    • 4
  • Ido Wolf
    • 2
  • Lior Orbach
    • 1
  • Eli Brazowski
    • 5
  • Ofer Isakov
    • 6
  • Joseph M. Klausner
    • 1
  • Nir Lubezky
    • 1
    Email author
  1. 1.Unit of Liver Surgery Department of SurgeryTel-Aviv Medical CenterTel AvivIsrael
  2. 2.Institute of OncologyTel-Aviv Medical CenterTel AvivIsrael
  3. 3.Department of EndocrinologyTel-Aviv Medical CenterTel AvivIsrael
  4. 4.Institute of GastroenterologyTel-Aviv Medical CenterTel AvivIsrael
  5. 5.Institute of PathologyTel-Aviv Medical CenterTel AvivIsrael
  6. 6.Department of Internal Medicine “T”Tel-Aviv Medical Center, (affiliated to the Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel.)Tel AvivIsrael

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