Pancreatic metastasis from renal cell carcinoma presenting as gastrointestinal hemorrhage: a case report

Abstract In some patients with metastatic renal cell carcinoma to the pancreas, gastrointestinal hemorrhages occur, but because of the rarity of this condition, treatment strategies have not been established. A 71-year-old man who had undergone a nephrectomy for renal cell carcinoma (RCC) went to a hospital in a state of shock. Computed tomography revealed a hypervascularized tumor in the head of the pancreas, suggesting metastatic RCC. Upper endoscopy revealed bleeding in the duodenum due to tumor invasion. An emergency angiogram showed that the tumor received its blood supply mainly from the gastroduodenal artery. Transarterial embolization (TAE) of the gastroduodenal artery was performed and bleeding was controlled. Two months after TAE, elective pancreaticoduodenectomy was performed. The patient currently continues to undergo outpatient follow-up 2 years later without recurrence. TAE was very effective in controlling the acute phase of severe gastrointestinal hemorrhage from pancreatic metastasis of RCC.


INTRODUCTION
In some patients with metastatic renal cell carcinoma (RCC) to the pancreas, gastrointestinal hemorrhages occur [1], but because of the rarity of this condition and the limited number of cases in the literature, treatment strategies for gastrointestinal hemorrhage caused by metastatic RCC to the pancreas have not been established [2]. We present a case of severe gastrointestinal hemorrhage causing the patient to enter a state of shock due to metastatic RCC to the pancreas.  White arrows indicate the tumor in the pancreas head and tail. duodenal invasion of the tumor in the pancreatic head. It was not possible to control the bleeding endoscopically and the patient was therefore transferred to our hospital for specialist treatment.
On examination, the patient had conjunctival pallor, blood pressure: 147/79 mmHg after transfusion and pulse: 95 beats per minute. Laboratory blood tests revealed a hemoglobin level at 7.8 g/dl. We decided to perform an emergency angiography which revealed a highly vascularized tumor at the pancreas head (Fig. 1a). The tumor was supplied with blood from a branch of the gastroduodenal artery. No extravasation of contrast medium was observed. Embolization of the anterior superior pancreatoduodenal artery and the right gastric epiploic artery was performed, and then also of the gastroduodenal artery, the right gastric epiploic artery, and the gastroduodenal artery. Angiography thereafter confirmed that all feeder arteries of the tumor had been embolized (Fig. 1b). Gastrointestinal hemorrhaging ceased after embolization. The patient did not complain of any abdominal pain after embolization and his medical condition was stable.
Subsequent contrast CT revealed two contrast-enhanced nodules in the pancreas head and tail ( Fig. 2) showing that the tumor which caused the bleeding had a reduced uptake of contrast agent. Esophagogastroduodenoscopy showed a submucosal tumor in the descending part of the duodenum. Positron emission tomography-CT revealed a lesion with weak fluorodeoxyglucose uptake at the pancreas head (maximum standardized uptake value: 2.1). There were no lesions with fluorodeoxyglucose uptake in the tail of the pancreas or other organs.
On the basis of these tests, we suspected that both of the tumors were due to multiple metastases of RCC to the pancreas. We performed pancreatoduodenectomy (PD) for the pancreas head tumor and partial pancreatectomy for the pancreas tail tumor. The patient was discharged on post-operative Day 20 without any complications. During 30 months of follow-up, there was no evidence of local recurrence or distant metastasis.
The effectiveness of transarterial embolization (TAE) for unresectable primary or metastatic disease in RCC patients has been established [6]. However, only a few studies have reported the effectiveness of TAE for bleeding due to metastatic RCC to the pancreas [2]. This may be because TAE is avoided due to risks of ischemic complications [2]. Although the upper gastrointestinal tract usually has a rich collateral blood supply, previous studies have shown that ischemic complications occur in 7-16% of cases [7,8]. A recent systematic review on embolization for nonvariceal upper gastrointestinal tract hemorrhage found a mean clinical success rate of 67%, while the mean rebleeding rate, mean complication rate and mean 30-day mortality were 27, 6 and 8%, respectively [9]. Based on these studies, a recent metaanalysis showed that TAE is a safe and effective procedure and could be a viable option for the first-line therapy of refractory non-variceal upper gastrointestinal tract hemorrhage [10]. Emergency PD, which is performed for bleeding, is accompanied by a higher frequency of complications than elective PD [11,12]. Tsai et al. reported overall complication and surgical mortality rates for emergency PD of 83.9 and 19.4%, respectively. Propensity score matching further indicated a significantly higher surgical mortality of emergency than elective PDs (19.4 vs. 3.2%) [12]. These investigators proposed that a possible explanation for the higher morbidity and mortality of emergency PD is that emergency surgery is always associated with a lesser degree of preparedness than elective surgery [12]. The treatment strategy of TAE followed by subsequent elective pancreatectomy may be effective both in acute and chronic phases of hemorrhagic events due to RCC.
When metastasis is limited to the pancreas, complete resection can result in a 5-year survival rate of 43-88% [13]. Analyzing 11 studies with five or more patients, which addressed pancreatic metastasis from RCC, Reddy et al. noted that in 7 studies (64%), the 5-year survival rate from the time of pancreatic resection was 80% [14]. A better prognosis after pancreatic metastasectomy can be achieved.
Pancreatic metastasis from RCC may present many years after resection of the primary RCC and it can present as upper gastrointestinal bleeding. TAE and elective pancreas resection may be effective both in acute and chronic phases of hemorrhagic events due to RCC.