The patient was a 10-year-old girl. Two months before admission, she experienced fullness in the upper right abdomen but could eat without nausea or vomiting. However, she has had a small meal since before and usually takes more than an hour to eat. When she complained of these signs to a former physician at the time of influenza vaccination, a liver tumor was suspected on echography and was referred to our department for an evaluation.
On admission, the patient’s height, weight and body mass index were 140 cm, 28.7 kg, and 14.6, respectively. The upper right abdomen was swollen and a mass was palpable. This mass was 10 cm in size, elastic, and hard with a clear border and no mobility. Blood tests on admission showed no increases in biliary enzymes, deviant liver enzymes, or tumor markers.
Echography on admission revealed that the mass was not related to the liver but was continuous with the pancreatic head. The inferior vena cava was pushed to the dorsal side, the portal vein was located on the left side, and the duodenum was shown on the right and ventral sides. The mass boundary was clear. No fatty liver or other liver abnormalities were observed. Contrast-enhanced computed tomography (CT) examination on admission showed a large tumor (94 × 85 × 75 mm) with a well-defined, smooth, thick capsular structure arising from the pancreatic head. Moreover, a thin septal structure with microcalcification was found in the tumor. Cystic and solid papillary components were observed (Fig. 1). Magnetic resonance imaging (MRI) on admission revealed tumor with a diameter of 10 cm in the pancreatic head.
Inside the tumor, T1-weighted imaging showed a high signal. In addition, in the solid part, T2-weighted imaging primarily showed an intermediate signal, with small cyst-like and slit-like hyperintensities mixed within, indicating that the solid and hemorrhagic degenerative necrotic components were mixed (Fig. 2). Bone scintigraphy on admission revealed no bone metastases.
A preoperative diagnosis of SPN in the pancreatic head was established. We planned to attempt enucleation at first, and possibly convert to PD, if enucleation was difficult.
Under general anesthesia, laparotomy (Fig. 3) was performed using a midline incision in the upper abdomen. The tumor was located on the dorsal side of the duodenum and pancreatic head. A small amount of ascites was found and submitted for cytopathology, and no tumor cells were detected. First, the duodenum and colon were detached from the tumor wall for enucleation. The parenchyma of the pancreatic head was confirmed, and the tumor was detached. Adhesions became severe in the vicinity of the pancreatic uncinate, and peeling was difficult, resulting in a cut into the pancreatic parenchyma. This part was inferred as the primary site, and postoperative pancreatic juice leakage was a strong concern. Therefore, enucleation was abandoned, and PD was performed. Although the tumor was strongly adhered to the superior mesenteric artery (SMA), it was removed. However, partial removal of the SMA plexus was necessary to remove the tumor without damaging it. In addition to subtotal stomach-preserving PD and modified Child reconstruction, Braun anastomosis was added. Pancreatojejunostomy was performed using pancreatojejunal mucosal anastomosis and the modified Blumgart method.
Examining the cut surface of the resected specimen confirmed that a thick capsule-like structure surrounded it and solid and hemorrhagic degenerative necrotic parts were mixed inside. The pathological findings confirmed a diagnosis of pancreatic SPNs.
The postoperative course is shown in Fig. 4. Oral water intake was started one day after the operation, and a fat-restricted diet was started 3 days postoperatively. No pancreatic juice leakage was observed. However, diarrhea and abdominal pain occurred on postoperative day four. The patient was discharged on postoperative day 10 because her symptoms gradually improved. Even after discharge, she had loose stools approximately three times a day. Furthermore, upon consumption of fatty food, she had diarrhea again and her abdominal pain worsened.
Immediately postoperatively, blood tests showed increases in serum aspartate aminotransferase (AST, 342 U/L) and alanine aminotransferase (ALT, 428 U/L), which were thought to be due to the operation. However, serum concentration of AST and ALT decreased one week after the operation to 31 U/L and 67 U/L, respectively. Subsequently, they gradually began to increase. The serum amylase levels did not exceed the upper limit of the reference range after surgery. One and a half months postoperatively, the patient’s abdominal pain and diarrhea worsened, and she was readmitted to the hospital. Tenderness was observed from the middle to the left side of the lower abdomen, with no peritoneal irritation. Blood test results showed no increases in white blood cells or CRP, and the serum amylase level was normal at 48 U/L. Deviant hepatic enzymes showed mild exacerbation of AST (78 U/L) and ALT (153 U/L), and the patient’s total cholesterol and body weight were the lowest at 94 mg/dL and 25.5 kg, respectively, on readmission. Abdominal radiography showed no niveau, and abdominal echography showed a mottled fatty liver (Fig. 5) and slight intrahepatic bile duct dilation with no dilation of the main pancreatic duct.
Based on these findings, the patient was diagnosed with fatty diarrhea, intestinal peristaltic pain, and NAFLD associated with pancreatic exocrine dysfunction without postoperative pancreatic duct passage obstruction. To supplement pancreatic digestive enzymes, pancrelipase containing high-titer amylase, lipase, and protease was started at 900 mg/day divided between three meals. Although abdominal pain was alleviated by relieving diarrheal stools, steatorrhea persisted. Therefore, the dose of pancrelipase was gradually increased, and antidiarrheal agents (albumin tannate and natural aluminum silicate) were added.
The dose of pancrelipase was increased to 2250 mg daily divided between meals, and by using it in combination with an antidiarrheal agent, abdominal pain was almost alleviated except for defecation. The patient was discharged because her feculence improved from muddy to loose stools. During follow-up at an outpatient clinic, abdominal pain and fat diarrhea stools recurred when food or fat intake increased.
Including dietary guidance, the dose of pancrelipase was increased to 2700 mg/day, and albumin tannate and natural aluminum silicate were increased to 4.5 g divided between meals. Since muddy stools were still frequent, loperamide hydrochloride was added a dose of 0.5 mg/day. However, natural aluminum silicate was discontinued to avoid the stools from becoming too hard, and albumin tannate was reduced to a dose of 1.5 g/day after lunch. Upon reducing the dose and taking 0.6 mg of loperamide hydrochloride after breakfast and dinner, loose stools could be relieved approximately two or three times a day. However, stools may change from muddy to loose stools, depending on the content and amount of food.
At the time of writing, one year and two months have passed since the operation. The patient’s height increased by 6 cm approximately one year postoperatively; she weighed 30.5 kg, and recovering from 25.5 kg at postoperative readmission to her preoperative weight. The patient currently attends school and after school lessons. Blood tests showed that AST remained at 50–60 U/L, ALT remained at 70–80 U/L, and total cholesterol level recovered to 147 mg/dL. The postoperative zinc levels have been within normal range. Although fatty liver remains to be observed on echography, no recurrence or metastasis of the pancreatic SPN was observed on CT.