Repeated Pancreatectomy for Metachronous Duodenal and Pancreatic Metastases of Renal Cell Carcinoma
A 50-year-old woman was referred to our hospital for treatment of a duodenal tumor. She had a 13-year history of left nephrectomy for RCC. The histologic diagnosis was clear cell carcinoma of grade 2, pT2N0M0, and pStage II (according to the current TNM staging of the Union for International Cancer Control, 7th edition). The postoperative course was uneventful, and no adjuvant therapy was administered.\nThree years after nephrectomy, the patient underwent external beam radiation therapy (a total of 46 Gy) for a solitary metastatic bone tumor in the seventh thoracic vertebra. A further 7 years later, a solitary metastatic tumor was detected in the tail of the pancreas, and resection of the pancreatic tail and spleen was performed. Since the histologic findings of the pancreatic tumor were similar to those of the kidney, metachronous metastasis of RCC to the tail of the pancreas was assumed. A further 3 years after resection of the pancreatic tail, severe anemia was detected during a regular examination. The patient mentioned the presence of persistent tarry stools for 3–4 weeks. Esophagogastroduodenoscopy (EGD) was performed and revealed a mass in the descending portion of the duodenum.\nThe patient was admitted to our hospital and underwent detailed examinations. Her hemoglobin level was 7.5 g/dl. A subsequent EGD revealed an ulcerated polypoid mass in the descending portion of the duodenum; the mass was adjacent to the oral side, but did not involve the papilla of Vater (fig. ). Endoscopic ultrasonography showed the tumor to be partially invading the head of the pancreas (fig. ). Duodenography revealed a protruding lesion at the wall of the pancreatic side of the descending portion of the duodenum (fig. ). Abdominal enhanced computed tomography depicted a well-contrasted, hypervascular mass (fig. ). Magnifying endoscopy showed a diminished mucosal surface pattern of the gastrointestinal epithelium across the surface of the tumor (fig. ). Furthermore, combined with narrow-band imaging (NBI), it also showed a highly dense assembly of microvessels on the surface of the tumor that did not form a capillary network pattern (fig. ). A duodenal biopsy was performed, and the histopathologic diagnosis was inflammatory granulation with no malignancy. An additional duodenal biopsy for histologic confirmation was not performed to avoid uncontrollable duodenal bleeding from the biopsy site. Although partial resection of the pancreas had already been performed for a metastatic tumor of the pancreatic tail, the remnant pancreas was of rich volume (fig. ). There was no evidence of metastasis to the lung, liver, lymph nodes or other organs. Enterography showed no abnormal findings suggestive of metastasis to the small intestine. Fluorodeoxyglucose (FDG)-positron emission tomography showed specific FDG uptake in the duodenal tumor (standardized uptake value [SUVmax] 6.1). No abnormally enhanced lesions were identified in the body. The levels of both carcinoembryonic antigen and carbohydrate antigen 19-9 were within normal ranges. Resultantly, our diagnosis was metachronous, solitary duodenal metastasis derived from RCC, and we therefore performed a pancreaticoduodenectomy.\nThere were no findings of malignant ascites, carcinomatosis, omental implants or distant metastases to other abdominal organs; we therefore subsequently performed a subtotal, stomach-preserving pancreaticoduodenectomy, choledochojejunostomy, pancreaticojejunostomy, and gastrojejunostomy with preservation of the left gastric artery and vein to maintain the supply and drainage blood flow to the stomach after splenectomy. The pancreas was dissected just above the portal vein. Regional lymph node dissection was minimized.\nMacroscopic findings of the resected specimen indicated that the polypoid mass at the descending portion of the duodenum was ulcerative and friable (fig. ). Histologic findings revealed that the surface of the tumor was coated by granulation tissue consisting of inflammatory cells, fibrosis and edematous stroma (fig. ). Furthermore, the cancerous lesion comprised clear cells containing glycogen that were arranged in an alveolar pattern (fig. ). The tumor had invaded the duodenal muscle and partially invaded the pancreas at a depth of 2 mm. Although the tumor was located very close to the lower common bile duct and main pancreatic duct, histologic direct invasion was not observed in either duct. Immunohistology showed that the tumor cells were positive for vimentin and CD10 and negative for CK7 (fig. ). The histologic diagnosis was metastatic RCC.\nThe patient experienced postoperative leakage from the gastrojejunostomy. After percutaneous drainage of the intra-abdominal abscess, she recovered and was discharged on postoperative day 59. One year after surgery, the patient maintained a good glucose tolerance and received only oral hypoglycemic agents and no insulin therapy. Furthermore, she had no evidence of re-bleeding or recurrence of RCC.