S3622 Ruptured Pancreatic Tumor Complicated by Pneumoperitoneum and Sepsis in a Chemotherapy-Dependent Patient: A Case Report

Introduction: Pancreatic cancer is a leading cause of cancer-related mortality, often diagnosed at advanced stages with limited therapeutic options. Tumor necrosis, infection, and abscess formation are common in these patients, particularly those undergoing chemotherapy. Pneumoperitoneum, the presence of air in the peritoneal cavity, is a rare but critical finding, frequently linked to gastrointestinal perforation. Case Description/Methods: A 77-year-old man with a history of pancreatic cancer undergoing chemotherapy, along with diabetes mellitus, hyperlipidemia, and obstructive sleep apnea, presented to the emergency department with worsening abdominal pain and fever over 2 days. On presentation, he was hypotensive, tachycardic, and tachypneic. Laboratory studies showed leukocytosis, elevated bilirubin, and transaminitis. Computed tomography abdomen and pelvis revealed a 3 cm necrotic pancreatic tumor with air in the superior left hepatic lobe, consistent with a ruptured tumor. Additionally, there was a 7 cm × 7 cm fluid collection, pneumoperitoneum, and air in the biliary tree. The patient was diagnosed with septic shock, secondary to peritonitis from the ruptured tumor. He was admitted to the intensive care unit for intravenous fluids, pressor support, and broad-spectrum antibiotics. A computed tomography-guided percutaneous drainage was performed, with cultures revealing Escherichia coli. After targeted antibiotic therapy, his clinical status improved. He was discharged with follow-up. Discussion: This case illustrates a rare but serious complication of pancreatic cancer: rupture of a necrotic tumor mass causing pneumoperitoneum and peritonitis. Advanced pancreatic tumors are prone to necrosis and infection due to their poor vascular supply. Tumor rupture contaminates the peritoneal cavity, leading to pneumoperitoneum and sepsis. The diagnosis was confirmed by computed tomography imaging, which showed air in the peritoneal cavity and complex fluid collections. The presence of air in the biliary tree and pancreatic mass suggested biliary involvement, complicating management. Early recognition of pneumoperitoneum in patients with advanced pancreatic cancer is critical. Prompt imaging, appropriate antibiotic therapy, and interventional management are essential for improving outcomes, especially in immunocompromised patients undergoing chemotherapy.