Multifocal pancreatic PPoma in the setting of MEN1: Case report and review of literature

Arman Mosenia; Casey Ward; Alisa Yee; Amir Qorbani; Carlos Corvera

doi:10.1016/j.ijscr.2021.106008

Multifocal pancreatic PPoma in the setting of MEN1: Case report and review of literature

Int J Surg Case Rep. 2021 Jun:83:106008. doi: 10.1016/j.ijscr.2021.106008. Epub 2021 May 23.

Authors

Arman Mosenia¹, Casey Ward², Alisa Yee³, Amir Qorbani⁴, Carlos Corvera⁵

Affiliations

¹ School of Medicine, University of California San Francisco, San Francisco, CA, USA. Electronic address: Arman.mosenia@ucsf.edu.
² Department of Surgery, University of California San Francisco, San Francisco, CA, USA. Electronic address: casey.ward@ucsf.edu.
³ Department of Surgery, Division of Surgical Oncology, University of California San Francisco, San Francisco, CA, USA. Electronic address: alisa.yee@ucsf.edu.
⁴ Department of Pathology, University of California San Francisco, San Francisco, CA, USA. Electronic address: amir.qorbani@ucsf.edu.
⁵ Department of Surgery, Division of Surgical Oncology, University of California San Francisco, San Francisco, CA, USA. Electronic address: Carlos.corvera@ucsf.edu.

Abstract

Introduction and importance: Functioning pancreatic neuroendocrine tumors (pNETs) that express pancreatic polypeptide-PPomas-do not yet have a pathognomonic clinical syndrome associated with them due to their overall rarity and diverse symptoms. Moreover, in patients with MEN1, the often multifocal nature of pNETs presents a unique clinical issue.

Case presentation: We report a case of a 22-year-old man with a known MEN1 gene mutation who was suffering from severe diarrhea (7-8 bowel movements per day) and was found to have only elevated PP levels on biochemical work-up. Ga68-DOTATATE PET/CT showed multifocal tumors in the body and tail of the pancreas that were not evident on contrast-enhanced CT. The patient underwent a successful laparoscopic radical antegrade modular pancreatosplenectomy (RAMP) and recovered well post-operatively with complete resolution of his diarrhea. Immunohistochemistry showed multiple pure PPomas.

Clinical discussion: This case highlights the unique propensity for multifocal disease in patients with MEN1 mutations and the utility of functional imaging by somatostatin analogs, i.e., Ga68-DOTATATE PET/CT, in order to perform oncologic laparoscopic pancreatic resections.

Conclusion: PPomas in the setting of MEN1 mutations are a unique clinical entity due to their diverse associated clinical syndromes and propensity for multifocal disease.

Keywords: Case report; Ga68-DOTATATE PET/CT; MEN1; Multifocal; PPoma; pNET.