The present case confirms pancreatoduodenectomy as an optimal treatment strategy under strict patient eligibility criteria, including stable circulatory dynamics and concomitant neighboring organ injury, even in elderly patients. Of note, the patient had a rare condition of a swollen duodenum from the second to the third segment that mimicked blunt trauma injury to the duodenum but was histologically diagnosed as primary FL of the duodenum. Definitive diagnosis is very difficult in cases of pancreatic injuries; close attention should be paid to other potential organ injuries to select the appropriate surgical procedure. The incidence of pancreatic injury has been reported to be less than 1% among cases of abdominal blunt trauma [8].
Optimal management of the pancreatic injury remains controversial for injuries of grades III or IV. As previously mentioned before, there are established opinions on the management policy for injuries of AAST-OIS grades I, II, and V. For grades III and IV injuries, surgical management is considered the basic optimal treatment. However, the type of surgical intervention has varied from drainage only, suturing repair, to pancreatic resection with or without immediate reconstruction [9]. Because the method cannot be easily selected, the probability of postoperative complications due to pancreatic resection or anastomosis in a pancreatic injury is as high as 40% [10]. Recently, some reports have suggested that NOM using endoscopic pancreatic duct stenting could be a useful and safe option in selected patients [11]. In this case, we selected PD because we suspected a co-existing duodenal injury. Due to its retroperitoneal location and proximity to the major vascular structures and other organs, isolated pancreatic injuries are rare [8, 12]. Thus, the wall thickening was suspected to reflect damage by the injury. However, the duodenal wall thickening was, in fact, due to primary duodenal FL, which was incidentally identified in the present case.
Primary gastrointestinal FL is rare, and among such cases, the frequency of primary duodenal FL is extremely rare at 3.6% [13]. Duodenal FL is mostly asymptomatic and often discovered incidentally by upper gastrointestinal endoscopy or diagnosed during a complication, such as a perforation [14]. To our knowledge, there is no report on FL incidentally identified because of a grade IV pancreatic injury. Immunostaining is useful for a definitive diagnosis, and FL can be diagnosed if bcl-2 is positive at the center of the lymphoid follicle. The prognosis of duodenal FL is better than that of other malignant lymphomas. An established treatment strategy has not been reported; “watch and wait” is currently acceptable for this slow-growing disease [15].
In the present case, suspicion of a widespread duodenal injury was the main reason for selecting pancreatoduodenectomy. Some reports have shown that in pancreatic injuries, pancreatoduodenectomy has high mortality (30%) and complication rates (80%) [16]. Furthermore, the risk of postoperative complications in pancreatoduodenectomy may be higher at age 75 years and older [17]. Thus, pancreatoduodenectomy is a very risky procedure, and adaptations should be carefully performed. With the aging society, the chances of encountering a case such as ours may increase. Highly invasive general abdominal surgeries, such as hepatectomy, are being applied to healthy elderly people [18]. Consistent with this, pancreatoduodenectomy might also be a useful treatment for elderly people with stable vital signs and suspected widespread duodenal injury.
