Pancreatic Imaging

Non-hypervascular pancreatic neuroendocrine neoplasms differentiation from CA19-9 negative pancreatic ductal adenocarcinomas based on contrast CT: A large sample series

PROPOSE

This study aims to evaluate the effectiveness of contrast-enhanced computed tomography (CT) in distinguishing non-hypervascular pancreatic neuroendocrine neoplasms (PNENs) from pancreatic ductal adenocarcinomas (PDACs) with a normal serum level of carbohydrate antigen 19-9 (CA19-9) levels.

METHODS

This retrospective study included 134 patients with pathologically confirmed non-hypervascular PNENs and 128 patients with CA19-9-negative PDACs, all of whom underwent contrast-enhanced CT prior to surgery between January 2015 and March 2024. Following independent evaluation by two radiologists, qualitative features from both groups were extracted in the arterial and portal venous phase and subsequently compared using univariate and multivariate analysis.

RESULTS

Patients with CA19-9 negative PDACs were significantly older than those with non-hypervascular PNENs (p < 0.001), and the majority of PDACs were located in the head of the pancreas (p < 0.01).Univariate analysis showed that non-hypervascular PNENs exhibited a higher frequency of well-defined tumor margins (p < 0.001) and calcification (p = 0.032) and a lower frequency of local invasion (p < 0.001), peripancreatic vascular invasion (p = 0.001), intra- or extrahepatic bile duct dilatation (p < 0.001), distal main pancreatic duct dilatation (p < 0.001), regional lymphadenopathy (p < 0.001) and tumor homogeneity (p < 0.001) when compared to CA19-9 negative PDACs. Multivariate analysis identified the absence of local invasion (Odds Ratio (OR) = 0.233; 95 % Confidence Internals (95 % CI):0.114-0.476; p < 0.001), absence of peripancreatic vascular invasion (OR = 0.434; 95 % CI:0.217-0.870; p = 0.019), a normal distal main pancreatic duct diameter (OR = 0.398; 95 % CI:0.202-0.785; p = 0.008), absence of regional lymphadenopathy (OR = 0.455; 95 % CI:0.238-0.870; p = 0.017) and tumor heterogeneity (OR = 0.240; 95 % CI:0.126-0.456; p < 0.001) as significant predictors of non-hypervascular PNENs. The area under the receiver operating characteristic curve for the radiological feature model was 0.829 based on logistic regression.

CONCLUSIONS

Qualitative features in contrast-enhanced CT images could be beneficial in differentially diagnosing non-hypervascular PNENs and CA19-9 negative PDACs.

Insulinoma Identified in Puerperium: Association with Pregnancy and Literature Review

Postpartum hypoglycemia in non-diabetic women is a rare condition. We report the case of a 34-year-old woman who experienced neuroglycopenia 2 days after delivery. Corresponding to severe hypoglycemia, we found inappropriately elevated insulin and C-peptide levels. Following magnetic resonance imaging a lesion of 10×8 mm was detected in the head of the pancreas. An ultrasound-guided fine needle aspiration of the mass confirmed the diagnostic suspicion of a pancreatic neuroendocrine tumor. Complete surgical enucleation of the insulinoma resulted in immediate and permanent resolution of the hypoglycemia. The postoperative course was uneventful. Histopathological and immunohistochemical analyses were consistent with insulinoma. The diagnostic approach to postpartum hypoglycemia represents a challenge for multidisciplinary teamwork.

LEARNING POINTS

Although insulinomas are extremely rare during pregnancy, most cases are recognized or become symptomatic during the first trimester.Symptoms of insulinomas may be initially masked due to changes in glucose metabolism and insulin resistance associated with pregnancy.In pregnancy, surgical treatment should be avoided whenever possible because of the risks to both mother and fetus; conservative treatment, including dietary intake, intravenous glucose and glucagon, should be initiated to control the hypoglycemia symptoms.

Surgical resection of pancreatic insulinoma during pregnancy: Case report and literature review

INTRODUCTION

Insulinomas are neuroendocrine tumors characterized by an excessive secretion of insulin, and its most common primary site is the pancreas.

PRESENTATION OF THE CASE

Female, 31 years old, who underwent surgical resection of a pancreatic insulinoma measuring 0.5 × 0.5 cm during the third trimester of pregnancy. The patient started to present characteristic symptoms (hypoglycemia, adrenergic and neuroglycopenic symptoms) 18 months before being referred to our center. It was decided to resect the lesion due to the intensity of the symptoms and failure of the clinical treatment. The postoperative course was uneventful, and the fetus presented good vitality, as evidenced by the obstetric ultrasound. The patient was discharged from the hospital on the 6th postoperative day. The neonate was born at term, 38 weeks, with appropriate weight for gestational age. Today, around 12 months after surgery, the patient and the infant are in good health conditions and have no complaints.

CONCLUSION

The moment of the surgical intervention in our case reflects the importance of this report, since it reinforces the feasibility of this procedure during pregnancy.

Diagnostic challenges in a patient with an occult insulinoma:68 Ga-DOTA-exendin-4 PET/CT and 68Ga-DOTATATE PET/CT

Despite growing evidence for GLP-1R molecular-based imaging, successful localization of insulinomas may require the use of multiple imaging modalities. Not all benign insulinomas express the GLP-1R as expected. Our case demonstrates that there is a still an important role for traditional methods for the anatomical localization of an insulinoma.