Background  Pancreatoblastoma (PBL) is a rare tumor, but it is the most common pancreatic malignant tumor in children. At present, only a few hundred cases have been reported at home and abroad, and there are fewer reports from multi-center and large-sample studies. Misdiagnosis or improper treatment may affect the prognosis due to insufficient understanding of PBL.

  Objective  To improve the understanding, diagnosis and treatment of PBL by analyzing the clinical features of children with PBL.

  Methods  A retrospective analysis was performed on 6 children with PBL admitted to the First Medical Center of Chinese PLA General Hospital from May 2012 to August 2021, and their clinical features, auxiliary examinations, treatments and outcomes were summarized.

  Results  Among the 6 cases, there were 5 boys and 1 girl, with a median age of 4 years and 7 months. The tumors were located at the junction of the head and body of the pancreas in 2 cases, the body-tail of the pancreas in 1 case, the tail of the pancreas in 2 cases, the whole pancreas in 1 case. There were 3 cases of portal vein involvement, 2 cases of splenic vein involvement, 1 case of lymph node metastasis, 1 case of multiple intrahepatic metastasis, and 1 case of peritoneal metastasis. Two cases were classified in stage I, 4 cases were in stage Ⅳ. Abdominal pain occurred in all cases. There were 2 cases of abdominal mass, 1 case of early satiety and weight loss, 1 case of vomiting and poor appetite, and 1 case of massive pelvic and abdominal effusion. AFP increased in 3 cases. Ultrasound (US) examination showed that lesions in 4 cases were isoechoic, 1 case inhomogeneous echo, 1 case hypoechoic, and 3 cases with calcification. Computed tomography (CT) of the tumors showed uneven density(high and low mixed) in 1 case, uneven density (equal and low mixed) in 1 case, low density in 3 cases, cystic solid in 1 case, 3 cases of , mild enhancement in 1 case. The immunohistochemical results showed that 1 case had no immunohistochemistry report; of the other 5 cases, 4 cases were Syn positive, 1 case was CD56 positive, 1 case was CD10 positive, 1 case was AFP positive, 3 cases were CK19 positive, 2 cases were AAT positive, and no case for CEA positive. Three cases underwent adjuvant chemotherapy and surgical resection, and they were followed up for 126, 46, and 40 months, respectively, without recurrence. One case simply underwent surgical resection, and there was no recurrence after 116 months of follow-up. Two cases received adjuvant chemotherapy, the tumors had shrunk but were still inoperable; one case gave up treatment and died; and the other case stopped treatment for 5 months without further tumor progression.

  Conclusion  PBL is a common pancreatic malignant tumor in children. Abdominal pain and abdominal mass are the most common clinical manifestations. AFP is significantly elevated in most patients, with US and CT as reliable auxiliary diagnostic methods. Complete surgical resection is the preferred treatment, and adjuvant chemotherapy can help complete tumor resection and improve prognosis. However, the design of chemotherapy regimens still needs multi-center and large-sample studies.