Abstract

Introduction Signet-ring cell carcinoma can arise from virtually all organs. Most signet-ring cell carcinoma arise from stomach (90%), while occurrence elsewhere within the gasterointestinal accounts for less than 1% of gastrointestinal malignancies. Signet-ring cell carcinoma may present with significant phenotypic variability, including cutaneous metastases7, though primary symptoms involving the pancreas are rare. Case report A Forty-eight-year-old male with no past medical history presented to the emergency department with abdominal pain, nausea, and vomiting. Laboratory data revealed normal electrolytes and liver function tests but a lipase of 525 units/liter. Computed tomography scan demonstrated soft-tissue stranding surrounding the pancreas with extensive mesenteric lymphadenopathy. He denied alcohol intake and additional data, including, IgG4, triglycerides and abdominal ultrasound were unrevealing. He was treated for acute pancreatitis. Following discharge he re-presented to the emergency department one week later with abdominal pain and jaundice. His liver function test were concerning for an obstructive process with alkaline phosphatase of 300IU/L, total bilirubin of 11.7 mg/dL, direct bilirubin of 7.5 mg/dL without transaminitis. Endoscopic retrograde cholangio pancreatography and endoscopic ultrasound demonstrated a heterogeneous mass at the pancreatic head. Fine needle aspiration of the mass and nodes revealed pathology consistent with signet-ring cell carcinoma with BRAF, KRAS, and TP53 mutations. Immunophenotype staining was pankeratin, keratin20, and CDX2 positive and cytokeratin7 negative, most consistent with a lower gastrointestinal primary. An esophagogastroduodenoscopy with random gastric biopsies was negative. Discussion We present a rare case of signet-ring cell carcinoma presenting as acute pancreatitis. Our case had an esophagogastroduodenoscopy with negative biopsies along with imaging that was unremarkable for any gastric primary. While there are few case reports that have had pancreatitis associated with signet-ring cell carcinoma, nearly all reported cases were from Ampulla of Vater metastasis which was not observed in our case. In conclusion we hope that by presenting our case we can broaden our knowledge of clinical scenarios of signet-ring cell carcinoma to hasten diagnosis and, subsequently, treatment.