What is groove pancreatitis?

Groove Pancreatitis: Definition and Clinical Entity

Groove pancreatitis is a rare, distinct form of chronic segmental pancreatitis that affects the anatomical "groove" space between the pancreatic head, the second portion of the duodenum, and the common bile duct. 1, 2

Anatomical Location and Pathophysiology

• The pancreaticoduodenal groove is the specific anatomical region involved, comprising the space bounded by the head of the pancreas, duodenum, and common bile duct 1, 3

• The pathophysiological mechanism involves chronic leakage of pancreatic juices into the pancreaticoduodenal groove, leading to progressive inflammation and fibrosis in this confined space 2

• This represents a segmental or focal form of chronic pancreatitis rather than diffuse pancreatic involvement 4, 5

Epidemiology and Risk Factors

• Groove pancreatitis predominantly affects men in their 4th-5th decade of life, with a significant male predominance 1

• Chronic alcohol abuse is the primary trigger, making it the most important modifiable risk factor 1, 2, 3

• Additional risk factors include:

  • Tobacco smoking 1
  • Pancreatic ductal stones 1
  • Pancreatic divisum 1
  • Annular pancreas 1
  • Ectopic/heterotopic pancreas 1, 5
  • Peptic ulcer disease 5
  • Duodenal wall thickening 1

Clinical Presentation

• Severe abdominal pain is the hallmark presenting symptom 1, 4

• Associated symptoms include:

  • Nausea and vomiting (often postprandial) 1, 4
  • Weight loss 1, 3, 4
  • Diarrhea 1
  • Jaundice (though notably less common than in pancreatic adenocarcinoma) 1, 5

Critical Diagnostic Challenge

The most important clinical pitfall is that groove pancreatitis closely mimics pancreatic adenocarcinoma both clinically and radiologically, leading to frequent misdiagnosis and unnecessary pancreaticoduodenectomies 2, 3, 4

• Groove pancreatitis accounts for 2.7% to 24.5% of pancreaticoduodenectomies performed for presumed chronic pancreatitis, highlighting the diagnostic difficulty 4

• Characteristic imaging findings that favor groove pancreatitis over malignancy include:

  • Duodenal wall thickening 2
  • Duodenal and paraduodenal cysts 2
  • Absence of cholestatic jaundice despite pancreatic head involvement 5
  • Presence of duodenal obstruction 5

• Endoscopic ultrasound (EUS) and magnetic resonance cholangiopancreatography (MRCP) are the preferred imaging modalities for diagnosis 5

• Fine needle aspiration via EUS is often nondiagnostic, and biopsy or surgical resection may be required for definitive diagnosis 2, 5

Management Implications

• Treatment is usually conservative with medical management, particularly in confirmed cases 2, 4

• Surgical intervention (Whipple procedure/pancreaticoduodenectomy) or interventional procedures (biliary drainage) are reserved for:

  • Cases where symptoms persist despite medical therapy 2, 3
  • Situations where malignancy cannot be definitively excluded 3, 4

• Prognosis is markedly different from pancreatic adenocarcinoma, making accurate diagnosis critical to avoid unnecessary major surgery 3

Clinical Recognition

Suspect groove pancreatitis in middle-aged men with chronic alcohol consumption presenting with persistent abdominal pain, weight loss, and imaging showing a pancreatic head mass without cholestatic jaundice. 3, 5 The low incidence is partly attributable to lack of clinical familiarity with this entity 5, and artificial intelligence applications in diagnostic imaging show promise for improving differentiation from malignancy 1.