Groove Pancreatitis in Focus: Tumor-Mimicking Phenotype, Diagnosis, and Management Insights

Groove pancreatitis (GP) is an uncommon pancreatic condition implying a challenging differential diagnosis. This study aims to comprehensively evaluate the main risk factors, clinical presentation, imaging and endoscopic characteristics of patients with GP, providing insights into an effective diagnostic approach and therapeutic strategies. Methods: A retrospective analysis was conducted on patients diagnosed with GP, with demographic and clinical data collected. The diagnostic route was followed by an upper endoscopy and was finally confirmed by cross-sectional imaging. In patients with high malignancy suspicion or with an uncertain diagnosis, a pancreatic endoscopic ultrasound (EUS) was further performed. According to imaging features, we divided patients into two categories: with and without tumor-like appearance. Results: Altogether, 23 patients were included, 11 in the tumor-like category, and 12 in the non-tumor-like group; 95.6% were men, 78.2% alcohol consumers, and 73.9% smokers. In both groups, the main symptom was abdominal pain, followed by nausea and vomiting. The most frequent finding at upper endoscopy was edematous duodenal mucosa (16 patients, 80%), followed by mucosal hyperemia (8 patients, 40%). The main finding at cross-sectional imaging was duodenal wall thickening (14 patients, 60.9%), followed by pancreatic head enlargement and duodenal wall cysts (both seen in 12 patients, 52.2%). The EUS predominantly showed duodenal wall thickening (13 patients, 68.4%), and intramural and paraduodenal cysts (10 patients, 52.6%). Conclusions: GP predominantly affects men with a history of chronic alcohol and tobacco use. Its primary diagnostic challenge lies in distinguishing it from pancreatic carcinoma, with an accurate diagnostic workup being crucial in clinical practice.