Pseudoprogression of lung large cell neuroendocrine carcinoma resembling pancreatic cancer during durvalumab therapy.

A 74-year-old Asian man was referred for numb and painful sensation in the right upper limb. He was diagnosed with lung large cell neuroendocrine carcinoma and started receiving durvalumab therapy as second-line treatment. Sixteen days after the first dose, laboratory examination revealed increased liver enzyme levels and a marked inflammatory response. Contrast-enhanced computed tomography revealed an unenhanced tumor measuring approximately 25 mm in the head of pancreas and dilation of the intra- and extra-hepatic bile ducts. Magnetic resonance cholangiopancreatography confirmed stricture in the lower common bile duct and main pancreatic duct. We suspected acute cholangitis caused by a pancreatic cancer and performed an endoscopic biliary drainage. Two weeks after the procedure, computed tomography revealed significant shrinkage of the tumor. The tumor gradually reduced and pseudoprogression in lung large cell neuroendocrine carcinoma was ultimately diagnosed. Acute cholangitis caused by pseudoprogression resembling pancreatic cancer during immune therapy has not yet been reported. We are mindful that pseudoprogression should be considered as a differential diagnosis if a rapidly developing pancreatic tumor is observed during immunotherapy.

Primary hepatic lymphoma diagnosed using endoscopic ultrasound-guided liver biopsy: a case report.

BACKGROUND: Because of the rarity of primary hepatic lymphomas, diagnosis of this disease entity may often be difficult, and performing a liver biopsy is the only way to establish a definitive diagnosis. Recently, endoscopic ultrasound-guided liver biopsy has emerged as a safe technique for obtaining liver tissue. However, there is no report on the use of endoscopic ultrasound-guided liver biopsy for diagnosing primary hepatic lymphomas. CASE PRESENTATION: An 85-year-old Asian man was admitted to our hospital because of multiple liver lesions without any identifiable primary tumor or extrahepatic lymphadenopathy. Serum tumor markers, including alpha-fetoprotein, were in the normal range. We provisionally diagnosed the patient with a cancer of unknown primary origin with liver metastases. An endoscopic ultrasound-guided fine needle liver biopsy of the tumor in the left lobe of the liver was performed using a transgastric approach, and histology revealed a primary hepatic lymphoma of a diffuse large B-cell lymphoma type. CONCLUSIONS: Primary hepatic lymphomas are quite rare, and diagnosis is often difficult without performing a biopsy. Endoscopic ultrasound-guided liver biopsy is a useful diagnostic modality even in such cases.

Needle tract seeding following endoscopic ultrasound-guided fine-needle aspiration for pancreatic cancer: a report of two cases.

BACKGROUND: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a useful tool in pancreatic cancer diagnosis. However, the procedure itself may cause peritoneal dissemination and needle tract seeding at the puncture site. We herein report two cases of gastric wall metastasis due to needle tract seeding after EUS-FNA. CASE PRESENTATION: Case 1: A 68-year-old woman was admitted to our hospital for persistent cough. Computed tomography (CT) scan revealed inflammatory changes in the left lung field, and incidentally, a 15-mm hypovascular mass was detected in the pancreatic body. She underwent EUS-FNA and was diagnosed as pancreatic adenocarcinoma. She underwent distal pancreatectomy with splenectomy; however, a small hard mass was observed in the posterior gastric wall during surgery. We performed partial gastrectomy, and the resected specimen was diagnosed as a needle tract seeding following EUS-FNA. She then underwent adjuvant chemotherapy with TS-1, but the pancreatic cancer showed recurrence 6 months after surgery. She died due to peritoneal dissemination 18 months after surgery. Case 2: A 70-year-old man was incidentally detected with a pancreatic body mass on a CT scan as part of his follow-up for recurrence of basal cell carcinoma. He underwent EUS-FNA and was diagnosed as pancreatic adenocarcinoma. He had nodules in both lungs, and it was difficult to differentiate them from lung metastasis of pancreatic cancer. Therefore, he underwent neoadjuvant chemoradiotherapy, and thereafter, the lung nodules showed no changes; hence, he underwent distal pancreatectomy with splenectomy. During surgery, we observed a hard mass in the posterior gastric wall. We performed partial gastrectomy, and the resected specimen was diagnosed as needle tract seeding due to EUS-FNA. He underwent chemotherapy with TS-1, and he is still alive 18 months after surgery at the time of writing. CONCLUSION: For resectable pancreatic body or tail tumors, EUS-FNA should be carefully performed to prevent needle tract seeding and intraoperative as well as postoperative assessment for gastric wall metastasis is mandatory.