Renal Cell Carcinoma and a Pancreatic Neuroendocrine Tumor: A Coincidence or Instance of Von Hippel-Lindau Disease?

Surgical resection of double advanced pancreatic neuroendocrine tumors with multiple renal cell carcinoma associated with von Hippel-Lindau disease

Von Hippel-Lindau (VHL) disease, an autosomal dominant genetic disorder caused by a germline mutation, is associated with non-functional and slow-growing pancreatic neuroendocrine tumor (PNET) and kidney cancer. We describe the case of a 46 year-old man with a 35 mm mass in the pancreatic head causing stricture of the bile duct and main pancreatic duct, a 55 mm mass in the pancreatic tail causing obstruction of the splenic vein (SV), and multiple masses of > 36 mm on both kidneys. We performed a two-stage resection. First, a total pancreatectomy with superior mesenteric vein (SMV) resection and reconstruction and retroperitoneoscopic right partial nephrectomy (NP) for five lesions was performed, followed by retroperitoneoscopic left partial NP of the five lesions 6 months later. Postoperative histopathological examination revealed NET G2 in the pancreatic head with SMV invasion and somatostatin receptor type 2A (SSTR2A) positivity, NET G2 in the pancreatic tail showed SV invasion and negative SSTR2A, and multiple clear cell renal cell carcinomas (RCC) were also noted. Multiple liver recurrences occurred 22 months after primary surgery. The patient remains alive 41 months after primary surgery. Kidney cancer generally determines VHL prognosis; however, we experienced dual-advanced PNETs with a more defined prognosis than multiple RCC associated with VHL.

Pancreatic neuroendocrine tumor with solitary splenic metastasis and synchronous renal cell carcinoma: A rare case report

Synchronous pancreatic neuroendocrine tumors and renal cell cancer are extremely rare. Von-Hipple-Landau syndrome is a major association. A 43-year-old male patient with left upper quadrant pain and significant weight loss was diagnosed with a synchronous pancreatic tail neuroendocrine tumor with solitary splenic metastasis and a clear-cell renal cell carcinoma of the left kidney. Sonography and a computed tomography scan of the abdomen showed a complex exophytic left renal mass and a necrotic lesion limited to the spleen. Although not apparent on preoperative imaging, distal pancreatic mass was also discovered intraoperatively. Subsequently, left radical nephrectomy, splenectomy, and distal pancreatectomy were performed, and the synchronous primaries and splenic metastasis were confirmed histopathologically. This case is unique in that it demonstrates multiple extremely rare events occurring simultaneously, namely pancreatic and kidney primaries, as well as solitary splenic metastasis.

Insulinoma Unmasked Post Sleeve Gastrectomy With Incidental Renal Cell Carcinoma: A Rare Case

Insulinoma is a functional pancreatic neuroendocrine tumor (pNET). Usually benign and solitary, these tumors present with recurrent episodes of hypoglycemia due to insulin hypersecretion. It's a rare cause of post bariatric surgery hypoglycemia and hence poses a diagnostic challenge. Here, we report the first case of a 53-year-old male with insulinoma unmasked post sleeve gastrectomy with incidental renal cell carcinoma (RCC). He presented with symptoms of Whipple's triad after two months of sleeve gastrectomy done for morbid obesity. On further inquiry, the patient gave a history of an asymptomatic peripancreatic neuroendocrine tumor (NET) for the past 11 years. With a suspicion of insulinoma, biochemical workup followed by non-invasive imaging like GA-68 DOTA and CT triphasic abdomen scan was done to guide the diagnosis of an insulinoma which also detected a second primary tumor in the right kidney, likely to be a malignant RCC. Following pancreatic mass excision with radical nephrectomy for right renal mass, histopathology (HPE) and immunohistochemistry (IHC) confirmed the diagnosis of an insulinoma and a right renal clear cell carcinoma. The patient was discharged with no further episodes of hypoglycemia. Hence, persistent hypoglycemia post bariatric surgery could be an indication of a hidden insulinoma and this possibility of synchronous tumors should be kept in mind when dealing with rare tumors like insulinoma.

Synchronous or metachronous presentation of pancreatic neuroendocrine tumor versus secondary lesion to pancreas in patients affected by renal cell carcinoma. Systematic review

The simultaneous or metachronous occurrence of pancreatic neuroendocrine tumor (panNET) and renal cell carcinoma (RCC) may represent a rare coincidence or a manifestation of von Hippel-Lindau disease (VHL). These two malignancies share both radiological and cytopathological features, making the differential diagnosis very challenging. In this review, we collected all cases of concurrent diagnosis of localized panNET and RCC, with or without VHL, as reported in the literature to date. We aimed to provide an insight into the differential diagnosis between panNET and RCC pancreatic metastasis with a focus on the optimal therapeutic algorithm depending on the diagnosis. We performed literature research in PubMed library databases for articles about coexisting panNET and RCC published from 2001 to 2018. We selected nine articles with a total of 13 patients, including one treated at our institution. Patients' median age was 49 years and eight out of 13 patients were women. VHL was diagnosed in nine cases. Most patients underwent radical nephrectomy for RCC (9/13) and a clear cell renal carcinoma variant was identified in six cases. The diagnosis of panNET was synchronous with RCC detection in nine cases and metachronous in four cases. The diameter of the pancreatic lesion was >2 cm in six cases. In two cases the panNET was misdiagnosed as metastatic RCC by radiological tests. Somatostatin receptor scanning was performed only in our patient (Octreoscan) showing intense uptake in the pancreatic mass. Endoscopic ultrasound fine needle aspiration of the pancreatic lesion was performed in four patients: in two cases the panNET was confused with metastatic RCC by cytological analysis. Most patients underwent pancreatic surgery (10/13) without histological confirmation. Clear cell panNET was recognized in six cases, while mixed neuroendocrine non-neuroendocrine neoplasm was diagnosed in one patient. Immunohistochemistry (IHC) staining showed positivity to typical neuroendocrine markers (chromogranin A and synaptophysin) in all reported tested cases (8/8). Three patients underwent systemic treatment: two patients received sunitinib and one patient interleukin-2 (IL-2). Other neoplasms were observed in seven patients, of whom six were affected by VHL syndrome. When neoplastic lesions are recognized in both the kidney and pancreas, panNET and RCC pancreatic metastasis are often misdiagnosed due to similar radiological and cytopathological features. An accurate differential diagnosis is crucial and IHC plays a central role in distinguishing the two entities. The therapeutic algorithm may change depending on the diagnosis: while pancreatic RCC metastases benefit from resection, in panNETs and VHL the indication for surgery must be carefully evaluated.

Rare Solid Tumor of the Exocrine Pancreas: A Pictorial Review

Numerous other solid primary neoplasms may arise from the pancreas besides primary ductal adenocarcinomas and neuroendocrine tumors. Although diagnosis can be difficult because of the very low incidence of these tumors, knowledge of several, typical, epidemiologic, biological, and imaging features can help obtain a correct diagnosis. This pictorial review describes the features of solid rare primary pancreatic neoplasms on computed tomography and magnetic resonance imaging focusing on characteristics that can help radiologists differentiate them from classical forms of ductal pancreatic adenocarcinoma and neuroendocrine tumors. Cystic pancreatic neoplasms are beyond the scope of the current review.