Increased FDG uptake of heterotopic pancreatitis in the stomach

Heterotopic Pancreas Masquerading as Omental Nodule on FAPI PET/CT

Chylous ascites, attributed to various etiologies including malignancy, tuberculosis, ruptured lymphatics, and congenital lymphatic disorders, manifests as abdominal distension. Our patient presented with this condition, and an elevated CA 125 prompted further investigation. Flourine-18 fluorodeoxyglucose positron emission tomography/computed tomography (PET-CT) revealed a metabolically inactive omental nodule, while gallium 68 fibroblast activation protein inhibitor (Ga-68-FAPI) PET-CT demonstrated uptake in the same nodule and low-grade uptake in bilateral adnexae. Colloid liver scan ruled out chronic liver disease. Surprisingly, lymphoscintigraphy showed no lymphatic leak. Histological examination of the omental nodule confirmed heterotopic pancreas (HP) in the small bowel mesentery, with normal adnexae. This case report illuminates the diagnostic challenges entailed in HP and signifies a pioneering instance in the literature where evidence of HP was identified for the first time on Ga-68-FAPI PET-CT during the investigative process.

FDG PET/CT in Pancreatic Ductal Adenocarcinoma Arising From a Heterotopic Pancreas of the Pylorus

ABSTRACT

Malignant transformation of heterotopic pancreas is extremely rare. We describe FDG PET/CT findings in a case of pancreatic ductal adenocarcinoma arising from a heterotopic pancreas in the submucosa of the pylorus with peripyloric lymph node metastasis and elevated serum carbohydrate antigen 19-9 level. The heterotopic pancreatic adenocarcinoma showed intense FDG uptake, and the peripyloric lymph node metastasis showed mild FDG uptake. This case indicates that heterotopic pancreatic adenocarcinoma should be included in the differential diagnosis of FDG-avid gastric submucosal lesions, especially in patients with elevated serum carbohydrate antigen 19-9 level.

Heterotopic Pancreas Mimicking Metastases From Renal Carcinoma: A Rare Differential

ABSTRACT

Heterotopic pancreas, also known as ectopic or aberrant pancreas, is described as the deposits of normal pancreatic tissue "dropped" into the developing gastrointestinal system. Here we present an operated case of renal clear cell carcinoma, which on 6-month follow-up presented with eccentric mass in the gastric body suspicious for malignancy. Endoscopic biopsy was inconclusive and showed isometabolism on 18F-FDG PET/CT. It was subsequently resected laparoscopically, and final histopathology revealed heterotopic pancreas.

Diagnosis of Ectopic Pancreas in Small Intestine With 18F-DOPA PET/CT

ABSTRACT

A 77-year-old man was referred for a PET/CT 18F-FDG after incidental discovery of a lobulated jejunal lesion during surgery for an abdominal aortic aneurysm. The lesion was not removed due to the risk of digestive perforation. PET/CT 18F-FDG did not show pathologic hypermetabolism. Subsequently, we decided to perform PET/CT 18F-DOPA to better characterize this incidentaloma. A moderate uptake was showed, less than the pancreas. After multidisciplinary discussion, taking into account macroscopic and imaging aspects, the hypothesis of an ectopic pancreas was retained, allowing the exclusion of surgical excision.

Ectopic Pancreatitis in the Gastric Antrum Mimicking Malignancy on FDG PET/CT

ABSTRACT

A 34-year-old man suffered intermittent abdominal pain for 1 month, especially after drinking or eating. Enhancement CT was performed to determine the cause, which detected a soft tissue mass in the gastric antrum, suggestive of possible malignancy. FDG PET/CT scan was undertaken for staging, which showed increased metabolism in the known gastric mass, also suggestive of malignancy. However, this lesion was confirmed as ectopic pancreatitis pathologically.

PET/CT Variants and Pitfalls in Liver, Biliary Tract, Gallbladder and Pancreas

A wide variety of pathological anomalies may occur in the liver, biliary system, and pancreas. It is a necessity to use many different imaging techniques in order to distinguish such varied pathologies, especially those from malignant processes. Positron Emission Tomography/Computed Tomography (PET/CT) is an imaging method that has proven its diagnostic value in oncology and can be used for different clinical purposes. Fluoro-18 fluoro-2-deoxy-D-glucose has a wide range of uses as a dominant radiopharmaceutical in routine molecular imaging, however, molecular imaging has started to play a more important role in personalized cancer treatment in recent years with new Fluoro-18 and Gallium-68 labeled tracers. Although molecular imaging has a strong diagnostic effect, the surprises and pitfalls of molecular imaging can lead us to unexpected and misleading results. Prior to PET/CT analysis and reporting, information about possible technical and physiological pitfalls, normal histological features of tissues, inflammatory pathologies, specific clinical features of the case, treatment-related complications and past treatments should be evaluated in advance to avoid misinterpretation. In this review, the physiological and pathophysiological variants as well as pitfalls encountered in PET/CT imaging of the liver, biliary tract, gallbladder, and pancreas will be examined. Other benign and malignant pathologies that have been reported to date and that have led to incorrect evaluation will be listed. It is expected that the devices, software, and artificial intelligence applications that will be developed in the near future will enable much more effective and faster imaging that will reduce the potential causes of error. However, as a result of the dynamic and evolving structure of the information obtained by molecular imaging, the inclusion of the newly developed radiopharmaceuticals in routine practice will continue to carry new potentials as well as new troubles. Although molecular imaging will be the flagship of diagnostic oncology in the 21st century, the correct analysis and interpretation by the physician will continue to form the basis of achieving optimal performance.

Increased 18F-FDG uptake of heterotopic pancreatitis in the small intestine: A CARE-compliant case report

BACKGROUD

Heterotopic pancreas (HP), a relatively uncommon congenital anomaly, is rarely noted during F-FDG positron-emission tomography/computed tomography (PET/CT) scan.

METHODS

A 60-year-old woman was referred to our hospital due to a 10-day history of abdominal pain with elevated levels of serum amylase and lipase. Abdominal CT and ultrasound examinations were negative. In order to search for the cause, an F-FDG PET/CT whole body scan was suggested to an old woman revealing the presence of F-FDG accumulating nodule in small intestine.

RESULTS

Surgical findings and pathologic results confirmed the diagnosis of small intestinal heterotopic pancreas with active chronic inflammation.

CONCLUSION

This uncommon case underscores the necessity of considering heterotopic pancreatitis in small intestine with focal F-FDG uptake as a possible differential diagnosis in intestinal tumor and tuberculosis.