Surgical resection of locally advanced paravisceral neuroganglioma

Abstract

Background: Neurogangliomas are rare, benign tumors of neural crest origin most commonly seen in the mediastinum/retroperitoneum and can involve critical vasculature. They are indolent and slow-growing tumors that present with symptoms based on mass effect and location. A 29-year old male presented with 2 months of worsening abdominal pain, early satiety, and diarrhea. Initial outside imaging revealed an indeterminate abdominal mass with EUS biopsy consistent with neuroganglioma. Triple phase CT revealed a large (10 x 7 x 9 cm) abdominal mass that appeared to arise from the right diaphragmatic crus and involving the paravisceral arteries of the abdominal aorta. Methods: The mass spared the left gastric artery but circumferentially encased the common hepatic artery with extension to the proper hepatic/gastroduodenal artery bifurcation, and circumferential encasement of the proximal splenic artery and superior mesenteric artery origin from the aorta extending down to the middle colic artery take-off with sparing of distal superior mesenteric root branches. The mass abutted the body/tail of the pancreas and anteriorly displaced the main portal, splenic vein and distal superior mesenteric vein with narrowing and there was encasement of the coronary vein. The left renal vein was involved and two right renal arteries were abutted but left renal artery uninvolved. After multidisciplinary discussion with no other viable treatment options in a highly symptomatic patient with a paravisceral ganglioneuroma, surgical resection was recommended Results: The patient was taken to the operating room for attempted vascular-sparing resection with plan for en bloc multi-arterial resection and reconstruction. A midline laparotomy was performed, the left lateral bisector was mobilized from its diaphragmatic attachments and reflected medially. The omentum was taken off transverse mesocolon, lesser sac entered and gastro-hepatic ligament divided. The right and left colon were mobilized and full Kocher maneuver performed. The medial wall of IVC and left renal vein and right renal arteries were dissected from the mass arising from the right diaphragmatic crus. The distal CHA at the proper hepatic/gastroduodenal bifurcation was dissected free and GDA was ligated. The omentum was divided close to the spleen and short gastric vessels ligated. The spleen and distal pancreas were dissected,mobilized in a retrograde fashion along left kidney/adrenal gland andIMV was ligated. The left diaphragmatic crus was divided and left renal artery preserved. Dissection was carried onto the aorta and the origins of the variant visceral vessels were isolated The splenic artery required ligation at its origin but the CHA and SMA origins preserved. Splenectomy was performed preserving the distal pancreas.The distal uninvolved SMA from the mesenteric root was dissected identifying the middle colic artery. The tumor was divided over the course of the SMA distally to its origin from the aorta circumferentially dissecting it from the encased SMA ligating several lateral pancreaticoduodenal branches going to the uncinate of the pancreas preserving distal jejunal mesenteric branches. Similarly the mass was dissected where it was encasing the common hepatic from the proper hepatic to the CHA origin with circumferential dissection of the vessel. Tumor was adherent to the portal vein and pancreas. Conclusion: Ligation of various venous tributaries including coronary vein was performed and tumor was carefully dissected off the uncinate and the specimen removed en bloc. Despite ligation of short gastric arteries and GDA there was still adequate arterial gastric inflow via the preserved right and left gastric arcade and this was confirmed with intraoperative Doppler signals and ICG injection under SPY device revealing good perfusion. Ganglioneuromas are rare, benign tumors that can arise in challenging anatomic locations with no other effective options other than resection. In our case pathology revealed benign paravisceral ganglioneuroma. Tumors involving visceral aortic branches require careful preoperative planning, experience with advanced resection and anatomical dissection, and attention to anatomical variants that can assist with R0 resection with minimal morbidity.