Giant serous microcystic adenoma of the pancreas safely resected after preoperative arterial embolization

Abstract

Serous microcystic adenomas are rare and account for 1-2% of all exocrine pancreatic tumors and 25% of all pancreatic cystic neoplasms. Recently, with advances in imaging techniques, these adenomas have been identified at an increasing frequency. A 63-year-old woman visited her doctor in 1999 due to a gastric deformity detected by upper gastrointestinal endoscopy. An abdominal computed tomography scan revealed a cystic lesion measuring 6.0 cm in diameter, resulting in a diagnosis of serous microcystic adenoma of the pancreatic head. During follow-up, the tumor increased steadily in size, measuring 6.0 cm in diameter in 1999 and 13.0 cm in 2008, while remaining asymptomatic throughout this period of time. The risk of malignant transformation appears to be low even over the long-term. However, some cases of malignant transformation to serous cystadenocarcinoma have recently been reported. In this case, assessment of the relationship between the tumor and adjacent vascular structures, such as massive drainage vein development on the surface or tumor flow into the portal and superior mesenteric veins and the celiac and superior mesenteric arteries, was critical for determining tumor resectability. The risk of massive intra-operative hemorrhage was felt to be considerable, given the extent of the veins on the surface of the tumor, as well as the size and location of the primary pancreatic mass. Therefore, preoperative embolization of the tumor-feeding arteries arising from the celiac axis (gastroduodenal, splenic and dorsal pancreatic arteries) was performed. Tumor resection with pancreaticoduodenectomy was performed without a blood transfusion, with an estimated blood loss of 570 ml. The final pathology confirmed the diagnosis of serous microcystic adenoma. The patient is currently alive and disease-free. Preoperative partial embolization of the tumor feeding arteries and intra-operative resection of the right gastric and inferior pancreatoduodenal arteries, allowed the tumor blood supply to be arrested without preoperative tumor necrosis. Subsequently, intraoperative blood loss was reduced. Preoperative partial embolization of the feeding arteries is useful for the resection of hypervascular large tumors of the pancreas.

Figure 1

Multi-detector row (MD) computed tomography scan. (A) A large hypervascular tumor measuring 13.0 cm in diameter at the head of the pancreas is shown. (B) In the arterial phase, the common hepatic artery (CHA) and gastroduodenal artery (GDA) are stretched widely across the surface of the tumor. (C) In the portal phase, the tumor arising from the pancreatic head showed posterior compression on the portal (PV) and superior mesenteric veins (SMV).

Figure 1

Multi-detector row (MD) computed tomography scan. (A) A large hypervascular tumor measuring 13.0 cm in diameter at the head of the pancreas is shown. (B) In the arterial phase, the common hepatic artery (CHA) and gastroduodenal artery (GDA) are stretched widely across the surface of the tumor. (C) In the portal phase, the tumor arising from the pancreatic head showed posterior compression on the portal (PV) and superior mesenteric veins (SMV).

Figure 1

Multi-detector row (MD) computed tomography scan. (A) A large hypervascular tumor measuring 13.0 cm in diameter at the head of the pancreas is shown. (B) In the arterial phase, the common hepatic artery (CHA) and gastroduodenal artery (GDA) are stretched widely across the surface of the tumor. (C) In the portal phase, the tumor arising from the pancreatic head showed posterior compression on the portal (PV) and superior mesenteric veins (SMV).

Figure 2

Angiography and preoperative embolization. (A) Early phase of the celiac axis arteriography showing feeding arteries to the tumor arising from arteries including the gastroduodenal, right gastric, splenic and dorsal pancreatic arteries. (B) Delayed phase of celiac axis arteriography showing numerous drainage veins on the surface of the tumor flowing into the PV. (C) Superior mesenteric artery (SMA) angiography showing the main feeding arteries to the inferior aspect of the tumor supplied by the inferior pancreatoduodenal artery (IPDA). (D) Preoperative embolization of the gastroduodenal, splenic and dorsal pancreatic arteries. Interlock embolization coils from the celiac axis was performed.

Figure 2

Angiography and preoperative embolization. (A) Early phase of the celiac axis arteriography showing feeding arteries to the tumor arising from arteries including the gastroduodenal, right gastric, splenic and dorsal pancreatic arteries. (B) Delayed phase of celiac axis arteriography showing numerous drainage veins on the surface of the tumor flowing into the PV. (C) Superior mesenteric artery (SMA) angiography showing the main feeding arteries to the inferior aspect of the tumor supplied by the inferior pancreatoduodenal artery (IPDA). (D) Preoperative embolization of the gastroduodenal, splenic and dorsal pancreatic arteries. Interlock embolization coils from the celiac axis was performed.

Figure 2

Angiography and preoperative embolization. (A) Early phase of the celiac axis arteriography showing feeding arteries to the tumor arising from arteries including the gastroduodenal, right gastric, splenic and dorsal pancreatic arteries. (B) Delayed phase of celiac axis arteriography showing numerous drainage veins on the surface of the tumor flowing into the PV. (C) Superior mesenteric artery (SMA) angiography showing the main feeding arteries to the inferior aspect of the tumor supplied by the inferior pancreatoduodenal artery (IPDA). (D) Preoperative embolization of the gastroduodenal, splenic and dorsal pancreatic arteries. Interlock embolization coils from the celiac axis was performed.

Figure 2

Angiography and preoperative embolization. (A) Early phase of the celiac axis arteriography showing feeding arteries to the tumor arising from arteries including the gastroduodenal, right gastric, splenic and dorsal pancreatic arteries. (B) Delayed phase of celiac axis arteriography showing numerous drainage veins on the surface of the tumor flowing into the PV. (C) Superior mesenteric artery (SMA) angiography showing the main feeding arteries to the inferior aspect of the tumor supplied by the inferior pancreatoduodenal artery (IPDA). (D) Preoperative embolization of the gastroduodenal, splenic and dorsal pancreatic arteries. Interlock embolization coils from the celiac axis was performed.

Figure 3

Laparotomy shows a large multicystic tumor arising from the head of the pancreas. A red vascular tape is looped under the gastroduodenal artery (GDA). Blue vascular tapes are looped under the PV and SMV at the upper and lower sides of the tumor, and a yellow vascular tape is looped under the transection line of the pancreatic body.

Figure 4

Microscopic features of the tumor. (A) The tumor is composed of multiple cysts lined with a single layer of cuboidal epithelium without atypia. H.E. Loupe. (B) Preoperative tumor embolization did not produce any changes, such as necrosis, that may interfere with visualization of the pathological features of the tumor. H.E. ×40.

Figure 4

Microscopic features of the tumor. (A) The tumor is composed of multiple cysts lined with a single layer of cuboidal epithelium without atypia. H.E. Loupe. (B) Preoperative tumor embolization did not produce any changes, such as necrosis, that may interfere with visualization of the pathological features of the tumor. H.E. ×40.