Pancreatic neuroendocrine carcinoma in a pregnant woman:A case report and review of the literature

BACKGROUND Portal venous thromboembolism caused by malignant pancreatic neuroendocrine tumor metastasis,as the initial presentation of portal hypertension and upper gastrointestinal bleeding,is a rare entity.To our knowledge,there are no reports of this entity in pregnant women.We describe a case of pancreatic neuroendocrine carcinoma during pregnancy with hematemesis and hematochezia as the initial presentation and review the literature to analyze the demographic,clinical,and pathological features to provide a reference for clinical diagnosis and treatment.CASE SUMMARY A 40-year-old woman presented with hematemesis and hematochezia at 26-wk gestation;she had no other remarkable medical history.The physical examination revealed normal vital signs,an anemic appearance,and lower abdominal distension.Abdominal color Doppler ultrasonography showed portal vein thrombosis,splenomegaly,intrauterine pregnancy,and intrauterine fetal death.Esophagogastroduodenoscopy revealed esophageal and gastric varicose veins and portal hypertensive gastropathy.Contrast-enhanced computed tomography demonstrated multiple emboli formation in the portal and splenic veins,multiple round shadows in the liver with a slightly lower density,portal vein broadening,varicose veins in the lower esophagus and gastric fundus,splenomegaly,bilateral pleural effusion,ascites and pelvic effusion,broadening of the common bile duct,and increased uterine volume.According to the results of Positron emission tomography-computed tomography and immunohistochemical staining,the final diagnoses were that the primary lesion was a pancreatic neuroendocrine tumor and that there were secondary intrahepatic metastases and venous cancer thrombogenesis.CONCLUSION Upper gastrointestinal bleeding in a pregnant woman may be caused by portal hypertension due to a malignant pancreatic neuroendocrine tumor.

Pancreatic neuroendocrine tumors G3 and pancreatic neuroendocrine carcinomas: Differences in basic biology and treatment

In 2017 the World Health Organization revised the criteria for classification of pancreatic neuroendocrine neoplasms(p NENs) after a consensus conference at the International Agency for Research on Cancer. The major change in the new classification was to subclassify the original G3 group into well-differentiated pancreatic neuroendocrine tumors G3(p NETs G3) and poorly differentiated pancreatic neuroendocrine carcinomas(p NECs), which have been gradually proven to be completely different in biological behavior and clinical manifestations in recent years. In 2019 this major change subsequently extended to NENs involving the entire digestive tract. The updated version of the p NENs grading system marks a growing awareness of these heterogeneous tumors. This review discusses the clinicopathological, genetic and therapeutic features of poorly differentiated p NECs and compare them to those of well-differentiated p NETs G3. For p NETs G3 and p NECs(due to their lower incidence), there are still many problems to be investigated. Previous studies under the new grading classification also need to be reinterpreted. This review summarizes the relevant literature from the perspective of the differences between p NETs G3 and p NECs in order to deepen understanding of these diseases and discuss future research directions.