Rare metastatic clear cell renal cell carcinoma to pancreas and duodenum revealed by EUS-guided fine-needle biopsy

Abstract

A 60-year-old male patient was diagnosed with clear cell renal cell carcinoma (ccRCC) 10 years ago (Figure 1) and underwent radical right nephrectomy. The patient recently presented with melena lasting 1 month. Gastroscopy revealed a mucosal elevation in the descending duodenum with an erythematous surface. An adjacent suspicious accessory papilla with possible active bleeding was noted. Hemostasis was achieved using endoscopic clips, and no further melena occurred (Figure 2). Contrast-enhanced computed tomography of the upper abdomen showed a pancreatic head/uncinate process lesion potentially invading the descending and horizontal segments of the duodenum, along with multiple slightly enlarged mesenteric lymph nodes (Figure 3). To clarify the nature of the lesion, EUS-guided fine-needle biopsy (FNB) was performed and identified a 2.6 cm × 2.4 cm hypoechoic mass in the pancreatic uncinate process, with irregular but well-defined margins, heterogeneous internal echoes (Figure 4). Under real-time EUS guidance, the lesion was punctured twice using a 22G Acquire needle, with 20 back-and-forth movements under 15 mL negative pressure. Pancreatic biopsy (cell block) identified atypical cells (Figure 5). Pancreatic cytology (liquid-based) demonstrated malignant cells consistent with metastatic ccRCC (Figure 6). The final diagnosis was metastatic ccRCC to the pancreatic uncinate process presenting as duodenal bleeding. Following multidisciplinary team discussion, the patient was deemed unsuitable for surgical resection because of duodenal