Xanthogranulomatous pancreatitis mimicking potentially malignant pancreatic neoplasm: report of a case

A case of progressive xanthogranulomatous pancreatitis with splenic abscess

Xanthogranulomatous inflammation is a chronic inflammatory reaction microscopically characterized by aggregation of foamy histiocytes, fibrous tissue, and infiltration of various inflammatory cells. In contrast to xanthogranulomatous inflammation in the gallbladder or kidney, xanthogranulomatous pancreatitis is rare. We herein present a case of xanthogranulomatous pancreatitis in a patient who underwent distal pancreatectomy with splenectomy under preoperative suspicion of a pancreatic pseudocyst or pancreatic tumor. A 77-year-old woman with a 1 month history of epigastric pain, anorexia, and general fatigue was admitted to our hospital. Contrast-enhanced computed tomography revealed a cystic mass with ill-defined margins at the pancreatic tail together with a splenic abscess. Contrast-enhanced endoscopic ultrasound detected a hyperechoic cystic lesion at the tail of the pancreas with heterogeneous internal echogenicity, and part of the intra-cystic content was enhanced by the contrast agent. Endoscopic retrograde cholangiopancreatography showed a cystic lesion at the tail of the pancreas that continued into the main pancreatic duct, and the main pancreatic duct was slightly narrowed downstream of the cystic lesion. Pancreatic juice cytology revealed suspicious cells, leading to the possibility of intraductal papillary mucinous carcinoma. Distal pancreatectomy with splenectomy was performed, and the histopathological diagnosis was xanthogranulomatous pancreatitis with no malignant findings.

Branch-duct Intraductal Papillary Mucinous Neoplasm with Rapidly Developing Intracystic Xanthogranulomatous Nodules

We herein report a case of a branch-duct intraductal papillary mucinous neoplasm (IPMN) with rapidly developing intracystic xanthogranulomatous nodules. A unilocular cystic lesion without a mural nodule was found in the pancreatic tail of a 69-year-old man. Ten months later, multiple mural nodules emerged unexpectedly within the cyst, and the patient underwent distal pancreatectomy. Based on immunohistochemical studies and a molecular analysis, we diagnosed him with branch-duct IPMN of the gastric immunophenotype. Fragility of the pancreatic duct mucosa and consequent exposure of the wall to pancreatic juice might have caused marked granulation nodule formation in the cyst lumen.

Carcinoembryonic Antigen Increase in a Patient with Colon Cancer Who Have Achieved Complete Remission and Negative 18F-FDG PET/CT: Don't Forget the Thyroid!

Serum carcinoembryonic antigen (CEA) is a tumor marker especially used to follow a patient with colorectal cancer. However, it is non-specific and could be increased in several cancers and some benign conditions. We report the case of a 70-year-old man followed since 2014 for a left colon adenocarcinoma with the persistence of an increased CEA. There was no evidence of recurrence, but a right lobar thyroid nodule without a significantly increased uptake was incidentally discovered on the CT scan of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET/CT. We suspected a medullary thyroid carcinoma (MTC) explaining the persistent elevation of CEA. Plasma calcitonin levels were 47 ng/L (N < 10). Fine needle aspiration cytology found atypia of undetermined significance and the patient was reluctant to undergo surgery without any further exploration. We performed a ¹⁸F-fluorodihydroxyphenylalanine (¹⁸F-FDOPA) PET/CT preoperatively which revealed a punctiform focus of the right thyroid lobe corresponding to a pT1aN1aMxR0 medullary thyroid carcinoma, histopathologically confirmed. This case highlights that despite the potential usefulness of ¹⁸F-FDG PET/CT in case of an unknown source of elevated CEA this imaging may be falsely negative as in the case of MTC and should lead to further explorations.

Xanthogranulomatous Pancreatitis Accompanied by Xanthogranulomatous Cholecystitis: A Case Report and Literature Review

ABSTRACT

Xanthogranulomatous pancreatitis (XGP) is extremely rare, with only 31 cases reported in the English literature to date. We reviewed previously reported 17 articles about XGP and report an additional case of XGP. This is the first case of XGP with xanthogranulomatous cholecystitis accompanied by intraductal papillary mucinous carcinoma (IPMC) in an 80-year-old woman. She was referred to our hospital with jaundice and general malaise and was found to have a cystic mass at the pancreatic head and a solid mass at the pancreatic tail, with dilation of both the main pancreatic duct and biliary tract noted on computed tomography. Diagnosis of IPMC at the pancreatic head with neuroendocrine tumor at the pancreatic tail was made, and the patient underwent subtotal stomach-preserving pancreatoduodenectomy with enucleation of the mass at the tail. Pathological examination revealed IPMC with xanthogranulomatous changes around the IPMC and at the pancreatic tail and gallbladder. Xanthogranulomatous pancreatitis could be induced by inflammatory reaction due to obstruction of the pancreatic duct and biliary tract by mucin produced in the IPMC. It is sometimes difficult to preoperatively differentiate XGP from malignant pancreatic tumors, such as pancreatic carcinoma or neuroendocrine tumor, using imaging studies.