Gastrointestinal tumors arising from autonomous nerves of Meisner?s or Auerbach?s plexus (plexomas and plexosarcomas) are rare tumors in only 87 cases described in the literature up to 2001. We present a very rare case of gastrointestinal stromal tumor (plexosarcoma) of the third and fourth portion of the duodenum, 130x98x87 mm in diameter, arising from its back wall, with central necrosis of the well circumscribed tumor, which communicated with the duodenum through an ulceration of 15x7mm in diameter, spreading towards the great vessels of the retroperitoneum. It was gradually and carefully removed, together with 17 cm of the duodenum and few centimeters of the jejunum with end-to-end duodenojejunostomy below the Vater?s papilla. During the removal of the tumor, the superior mesenteric artery, being within the tumor?s capsule, was accidentally ligated but not transsected. In spite of the removal of the ligature, the artery became thrombosed due to damage of the intima by ligature so that it had to be resected and reanastomosed. After otherwise uneventful recovery, except for a mild pus discharge through the drain, not far from the arterial anastomosis, the patient suddenly started bleeding on the 13th day after surgery. At emergency reoperation, a rupture of the mesenteric artery above the thrombosed anastomosis was found. In spite of absence of the arterial pulsation within the mesentery, the bowel looked vital and the back flow from the artery was satisfactory. The arterial rereconstruction was not possible, so the artery was ligated. The postoperative recovery was surprisingly uneventful. The patient was discharged ten days after surgery and has stayed symptom-free so far. .
Anatomical analysis of the basilar artery and its branches with special reference to the arterial anastomosis, and its course and distribution on the pontine ventral surface.
