Pancreatic serous cystoadenoma (CSA) showing increased tracer uptake at 68-GaDOTA-peptide Positron Emission Tomography (68Ga-DOTA-peptide PET-CT): a case report

Abstract

Background Serous cysto-adenoma (SCA) is a rare benign neoplasm of the pancreas. SCA can mimic other pancreatic lesions, such as neuroendocrine tumours. 68Gallium-DOTA-peptide Positron Emission Tomography (PET) is able to image in vivo the over-expression of the somatostatin receptors, playing an important role for the identification of neuroendocrine neoplasms. Case presentation We reported a case of 63-year-old man, with a solid lesion of 7 cm of diameter of the body–tail of the pancreas. Two fine-needle-aspirations (FNA) were inconclusive. A 68Ga-DOTA-peptide PET-CT revealed a pathological uptake of the pancreatic lesion. The diagnosis of a pancreatic neuroendocrine neoplasm was established and a laparoscopic distal splenopancreatectomy and cholecystectomy was performed. Final histopathological report revealed the presence of a micro-cystic SCA. Conclusions The current case firstly reports a pancreatic SCA showing increased radiopharmaceutical uptake at 68Ga-DOTA-peptide PET-CT images. This unexpected finding should be taken into account during the diagnostic algorithm of a pancreatic lesion, in order to minimize the risk of misdiagnosis and overtreatment of SCA.

Increased Uptake in Microcystic Serous Cystadenoma Mimicking Pancreatic Neuroendocrine Tumor on 68Ga-DOTATATE PET/MRI

“…This indicates that PET/CT is helpful in the diagnosis of pancreatic neuroendocrine tumor when tumor uptake of 68 Ga-DOTA somatostatin analogs is observed. But false-positive results can also occur, as demonstrated by serous cystadenoma of the pancreas with 68 Ga-DOTATOC PET/CT uptake, as reported previously 5–7 . The current case showed that a pancreatic serous cystadenoma may display moderate 68 Ga-DOTATATE uptake at the edge of the lesion on PET/MRI.…”

“…But false-positive results can also occur, as demonstrated by serous cystadenoma of the pancreas with 68 Ga-DOTATOC PET/CT uptake, as reported previously. [5][6][7] The current case showed that a pancreatic serous cystadenoma may display moderate 68 Ga-DOTATATE uptake at the edge of the lesion on PET/MRI. The superior soft-tissue resolution of MRI is able to reveal the high fluid content of serous cystadenoma, especially in DWI.…”

Pancreatic serous cystadenoma with a high 68Ga DOTATOC-uptake mimicking a pancreatic NET

“…They are not expressed in pancreatic adenocarcinoma, but are found in some 90% of the P-NETs [5,9]. They have not been known to be expressed in pancreatic cystic neoplasms, and when reported by Nappo et al in 2020 this was claimed to be the first report of this finding in a serous cystadenoma [10]. No somatostatin positive pancreatic mucinous cystic neoplasm has been reported, and to our knowledge, nor in the cystadenomatous analogues originating from other organs such as the ovaries.…”

Management recommendations for pancreatic manifestations of von Hippel–Lindau disease

“…Additionally, a pancreatic cystadenoma may mimic a PNET in patients with VHL but has a very low malignant potential. 48,53…”