Acute recurrent pancreatitis: Etiopathogenesis,diagnosis and treatment

Acute recurrent pancreatitis(ARP)refers to a clinical entity characterized by episodes of acute pancreatitis which occurs on more than one occasion.Recurrence of pancreatitis generally occurs in a setting of normal morpho-functional gland,however,an established chronic disease may be found either on the occasion of the first episode of pancreatitis or during the follow-up.The aetiology of ARP can be identified in the majority of patients.Most common causes include common bile duct stones or sludge and bile crystals;sphincter of oddi dysfunction;anatomical ductal variants interfering with pancreatic juice outflow;obstruction of the main pancreatic duct or pancreatico-biliary junction;genetic mutations;alcohol consumption.However,despite diagnostic technologies,the aetiology of ARP still remains unknown in up to 30%of cases:in these cases the term“idiopathic”is used.Because occult bile stone disease and sphincter of oddi dysfunction account for the majority of cases,cholecystectomy,and eventually the endoscopic biliary and/or pancreatic sphincterotomy are curative in most of cases.Endoscopic biliary sphincterotomy appeared to be a curative procedure per se in about 80%of patients.Ursodeoxycholic acid oral treatment alone has also been reported effective for treatment of biliary sludge.In uncertain cases toxinbotulin injection may help in identifying some sphincter of oddi dysfunction,but this treatment is not widely used.In the last twenty years,pancreatic endotherapy has been proven effective in cases of recurrent pancreatitis depending on pancreatic ductal obstruction,independently from the cause of obstruction,and has been widely used instead of more aggressive approaches.     

Autoimmune pancreatitis: Multimodality non-invasive imaging diagnosis

Autoimmune pancreatitis(AIP)is characterized by obstructive jaundice,a dramatic clinical response to steroids and pathologically by a lymphoplasmacytic infiltrate,with or without a pancreatic mass.Type 1AIP is the pancreatic manifestation of an Ig G4-related systemic disease and is characterized by elevated Ig G4serum levels,infiltration of Ig G4-positive plasma cells and extrapancreatic lesions.Type 2 AIP usually has none or very few Ig G4-positive plasma cells,no serum Ig G4 elevation and appears to be a pancreas-specific disorder without extrapancreatic involvement.AIP is diagnosed in approximately 2%-6%of patients that undergo pancreatic resection for suspected pancreatic cancer.There are three patterns of autoimmune pancreatitis:diffuse disease is the most common type,with a diffuse,“sausage-like”pancreatic enlargement with sharp margins and loss of the lobular contours;focal disease is less common and manifests as a focal mass,often within the pancreatic head,mimicking a pancreatic malignancy.Multifocal involvement can also occur.In this paper we describe the features of AIP at ultrasonography,computed tomography,magnetic resonanceand positron emission tomography/computed tomography imaging,focusing on diagnosis and differential diagnosis with pancreatic ductal adenocarcinoma.It is of utmost importance to make an early correct differential diagnosis between these two diseases in order to identify the optimal therapeutic strategy and to avoid unnecessary laparotomy or pancreatic resection in AIP patients.Non-invasive imaging plays also an important role in therapy monitoring,in follow-up and in early identification of disease recurrence.     

Autoimmune pancreatitis： Functional and morphological recovery after steroid therapy

Autoimmune pancreatitis, a recently recognized type of chronic pancreatitis, is not rare in Japan, but reports of it elsewhere are relatively uncommon. We report the first preoperatively diagnosed case of autoimmune pancreatitis in Hungary, which responded well to steroid treatment and provided radiographic and functional evidence of this improvement. A 62-year-old female presented with a 4-month history of recurrent epigastric pain and a 5-kg weight loss. The oral glucose tolerance test (OGTT) indicated diabetes mellitus and the result of the fecal elastase test was abnormal. Ultrasonography (US) and the CT scan demonstrated a diffusely enlarged pancreas, and endoscopic retrograde cholangiopancrea-tography (ERCP) an irregular main pancreatic duct with long strictures in the head and tail. Autoimmune pancreatitis was diagnosed. The patient was started on 32 mg prednisolone daily. After 4 wk, the OGTT and faecal elastase test results had normalized. The repeated US and CT scan revealed a marked improvement of the diffuse pancreatic swelling, while on repeated ERCP, the main pancreatic duct narrowing was seen to be ameliorated. It is important to be aware of this disease and its diagnosis, because AIP can clinically resemble pancreatobiliary malignancies, or chronic or acute pancreatitis. However, in contrast with chronic pancreatitis, its symptoms and morphologic and laboratory alterations are completely reversed by oral steroid therapy.     

A rare etiology of post-endoscopic retrograde cholangiopancreatography pneumoperitoneum

Major complications of endoscopic retrograde cholangiopancreatography （ERCP） include pancreatitis, hemorrhage, cholangitis, and duodenal perforation. The occurrence of free air in the peritoneal cavity post- ERCP is a rare event （〈 1%）, which is usually the result of duodenal or ductal perforation related to therapeutic ERCP with sphincterotomy. We describe for the first time a different aetiology of pneumoperitoneum, in an 84-year-old woman with pancreatic cancer and a large hepatic metastasis, after ERCP with common bile duct stent deployment. Our patient developed, pneumoperitoneum due to air leakage from rupture of intrahepatic bile ducts and Glisson’s capsule in the area of a peripheral large hepatic metastasis. The potential mechanism underlying this complication might be post- ERCP pneumobilia and increased pressure of intrahepatic bile ducts leading to rupture of intrahepatic bile ducts in the liver metastatic mass owing to neoplastic tissue friability. This case indicates the need for close clinical and radiological observation of patients with hepatic masses （primary or metastatic） subjected to ERCP. In such patients, avoidance of excessive air insufflation during ERCP and/or placement of a nasogastric tube for bowel decompression immediately after ERCP might be a reasonable strategy to prevent such unusual complications.     

Head mass in chronic pancreatitis: Inflammatory or malignant

Chronic pancreatitis increases the risk of developing pancreatic cancer. This often presents as a mass lesion in the head of pancreas. Mass lesion in the head of pancreas can also occur secondary to an inflammatory lesion. Recognising this is crucial to avoid unnecessary surgery. This is sometimes difficult as there is an overlap in clinical presentation and conventional computed tomography(CT) abdomen findings in inflammatory andmalignant mass. Advances in imaging technologies like endoscopic ultrasound in conjunction with techniques like fine needle aspiration, contrast enhancement and elastography as well as multidetector row CT, magnetic resonance imaging and positron emission tomography scanning have been shown to help in distinguishing inflammatory and malignant mass. Research is ongoing to develop molecular techniques to help characterise focal pancreatic mass lesions. This paper reviews the current status of imaging and molecular techniques in differentiating a benign mass lesion in chronic pancreatitis and from malignancy.     

Is endoscopic therapy the treatment of choice in all patients with chronic pancreatitis?

Chronic pancreatitis(CP) is a progressive inflammatory disease of the pancreas characterized by destruction of the pancreatic parenchyma with subsequent fibrosis that leads to pancreatic exocrine and endocrine insufficiency.Abdominal pain and local complications(bile duct or duodenal stenosis and pancreatic tumor) secondary to CP are indications for therapy.At the beginning,medical therapy is used.More invasive treatment is recommended for patients with pancreatic duct stones(PDS) and pancreatic obstruction in whom standard medical therapy is not sufficient.Recently,Clarke et al assessed the long-term effectiveness of endoscopic therapy(ET) in CP patients.The authors compared ET with medical treatment.They reported that ET was clinically successful in 50% of patients with symptomatic CP.In this commentary,current CP treatment,including indications for ET and surgery in CP patients,is discussed.Recommendations for endoscopic treatment of CP according to the European Society of Gastrointestinal Endoscopy Clinical Guidelines are reviewed.Different surgical methods used in the treatment of CP patients are also discussed.ET is the most useful in patients with large PDS,pancreatic duct obstruction and dilation.It should be the first-line option because it is less invasive than surgery.Surgery should be the first-line option in patients in whom ET has failed or in those with a pancreatic mass with suspicion of malignancy.ET is a very effective and less invasive procedure,but it cannot be recommended as the treatment of choice in all CP patients.     

Acute pancreatitis： Etiology and common pathogenesis

Acute pancreatitis is an inflammatory disease of the pancreas. The etiology and pathogenesis of acute pancreatitis have been intensively investigated for centuries worldwide. Many causes of acute pancreatitis have been discovered, but the pathogenetic theories are controversial. The most common cause of acute pancreatitis is gallstone impacting the distal common bile-pancreatic duct. The majority of investigators accept that the main factors for acute billiary pancreatitis are pancreatic hyperstimulation and bile-pancreatic duct obstruction which increase pancreatic duct pressure and active trypsin reflux.Acute pancreatitis occurs when intracellular protective mechanisms to prevent trypsinogen activation or reduce trypsin activity are overwhelmed. However, little is known about the other acute pancreatitis. We hypothesize that acute biliary pancreatitis and other causes of acute pancreatitis possess a common pathogenesis. Pancreatic hyperstimulation and pancreatic duct obstruction increase pancreatic duct pressure, active trypsin reflux, and subsequent unregulated activation of trypsin within pancreatic acinar cells. Enzyme activation within the pancreas leads to auto-digestion of the gland and local inflammation. Once the hypothesis is confirmed, traditional therapeutic strategies against acute pancreatitis may be improved. Decompression of pancreatic duct pressure should be advocated in the treatment of acute pancreatitits which may greatly improve its outcome.     

Carcinoma in situ arising in a tubulovillous adenoma of the distal common bile duct： A case report

Tubulovillous adenomas are common in the colon and rectum, but are rare in the common bile duct. Biliary adenomas may produce obstructive jaundice, which can be easily confused with a malignant neoplasm or stone. We report a case of a carcinoma in situ arising in a tubulovillous adenoma of the distal common bile duct causing obstructive jaundice. A 55-year-old male presented with a 10-d history of pruritus and progressive jaundice. Abdominal sonography and computed tomography showed a mass in the distal common bile duct. Endoscopic retrograde cholangiopancreatography showed luminal narrowing of the bile duct due to a polypoid mass. Positron emission tomography demonstrated no abnormal uptake. It was thought that this mass was a malignant tumor, thus a pylorus-preserving panceaticoduodenectomy was performed. The final pathology showed a tubulovillous adenoma with carcinoma in situ of the distal common bile duct. At follow-up 8 mo later, endoscopy showed multiple polyps in the rectum, colon and stomach. The polyps were removed by endoscopic mucosal resection and shown to be tubular adenomas with high grade dysplasia. Biliary adenomas require careful follow-up for early detection of recurrence and malignant transformation.     

Double common bile duct： A case report

Double common bile duct （DCBD） is a rare congenital anomaly in which two common bile ducts exist. One usually has normal drainage into the papilla duodeni major and the other usually named accessory common bile duct （ACBD） opens in different parts of upper gastrointestinal tract （stomach, duodenum, ductus pancreaticus or septum）. This anomaly is of great importance since it is often associated with biliary lithiasis, choledochal cyst, anomalous pancreaticobiliary junction （APBJ） and upper gastrointestinal tract malignancies. We recently recognized a rare case of DCBD associated with APB3 with lithiasis in better developed common bile duct. The opening site of ACBD was in the pancreatic duct. The anomaly was suspected by transabdominal ultrasonography and finally confirmed by endoscopic retrograde cholangiopancreatography （ERCP） followed by endoscopic sphincterotomy and stone extraction. According to the literature, the existence of DCBD with the opening of ACBD in the pancreatic duct is most frequently associated with APB3 and gallbladder carcinoma. In case of DCBD, the opening site of ACBD is of greatest clinical importance because of its close implications with concomitant pathology. The adequate diagnosis of this rare anomaly is significant since the operative complications may occur in cases with DCBD which is not recognized prior to surgical treatment.     

IgG4-related sclerosing disease

Based on histological and immunohistochemical exami- nation of various organs of patients with autoimmune pancreatitis （AIP）, a novel clinicopathological entity of IgG4-related sclerosing disease has been proposed. This is a systemic disease that is characterized by extensive IgG4-positive plasma cells and T-lymphocyte infiltration of various organs. Clinical manifestations are apparent in the pancreas, bile duct, gallbladder, salivary gland, retroperitoneum, kidney, lung, and prosrate, in which tissue fibrosis with obliterative phlebitis is pathologically induced. AlP is not simply pancreatitis but, in fact, is a pancreatic disease indicative of IgG4- related sclerosing diseases. This disease includes AlP, sclerosing cholangitis, cholecystitis, sialadenitis, retro-peritoneal fibrosis, tubulointerstitial nephritis, interstitial pneumonia, prostatitis, inflammatory pseudotumor and lymphadenopathy, all IgG4-related. Most IgG4-related sclerosing diseases have been found to be associated with AlP, but also those without pancreatic involvement have been reported. In some cases, only one or two organs are clinically involved, while in others, three or four organs are affected. The disease occurs predominantly in older men and responds well to steroid therapy. Serum IgG4 levels and immunos-taining with anti-IgG4 antibody are useful in making the diagnosis. Since malignant tumors are frequently suspected on initial presentation, IgG4-related sclerosing disease should be considered in the differential diagnosis to avoid unnecessary surgery.     

Autoimmune pancreatitis associated with retroperitoneal fibrosis

CONTEXT: Autoimmune pancreatitis is sometimes associated with other autoimmune diseases. We have presented two cases of autoimmune pancreatitis with retroperitoneal fibrosis and compared our findings with those found in the literature. CASE 1: A 71-year-old male developed anorexia and weight loss. Abdominal ultrasonography (US) and computed tomography (CT) showed diffuse swelling of the pancreas and the peritoneal soft tissue surrounding the aorta, associated with right hydronephrosis. Endoscopic retrograde pancreatography showed narrowing of the main pancreatic duct. He was diagnosed as having autoimmune pancreatitis associated with retroperitoneal fibrosis and underwent steroid therapy. After 3 weeks, a follow-up CT showed a marked reduction in the size of both the pancreas and retroperitoneal mass. CASE 2: A 62-year-old male was admitted to another hospital complaining of obstructive jaundice. Abdominal CT and US showed swelling of the pancreas. Endoscopic retrograde cholangiopancreatography demonstrated stenosis of the lower bile duct and narrowing of the main pancreatic duct. With the diagnosis of pancreatic head carcinoma, a choledochojejunostomy and a gastrojejunostomy were performed. Histological examination of the biopsy of the pancreatic mass revealed marked fibrosis with lymphoplasmacytic infiltration. One year later, a retroperitoneal mass was detected on follow-up CT. He was treated with prednisolone for two years. Recurrence of retroperitoneal mass with left hydronephrosis occurred 18 months later. There was no sign of recurrence of the autoimmune pancreatitis. He was again treated with prednisolone, and the retroperitoneal mass was gradually reduced. CONCLUSIONS: A total of 7 cases including the present cases have been reported. All were middle-aged males. Steroid therapy was effective for both the pancreatic and the retroperitoneal masses.     

Spontaneous regression of a pancreatic head mass and biliary obstruction due to autoimmune pancreatitis.

BACKGROUND: Autoimmune pancreatitis is an evolving entity. METHODS: A patient who had spontaneous regression of a pancreatic head mass and biliary obstruction due to autoimmune pancreatitis is presented. RESULTS: A 58-year-old diabetic woman with jaundice was referred for pancreatic head carcinoma diagnosed by magnetic resonance imaging (MRI). At laparotomy, a pancreatic head mass (4 x 3 cm) that involved the transverse mesocolon and two other hard masses (1 cm) in the pancreatic body and tail were found. The gallbladder was palpated as a hard tumor mass. Frozen section examination of the gallbladder and pancreatic biopsies revealed cholecystitis and pancreatitis with lymphoplasmacytic infiltration. The common bile duct was brittle and unsuitable for anastomosis. Starting 1 month after the operation, drainage from the biliary catheter decreased gradually and stopped. There was no parenchymal lesion on MRI examination in the 2nd postoperative month. Cholangiography from the percutaneous catheter showed flow of contrast agent into the duodenum. Serum immunoglobulin G, G4 and E levels were increased. CONCLUSION: To the best of our knowledge, this is the first report of spontaneous regression of a pancreatic head mass and biliary obstruction due to autoimmune pancreatitis.     

ERCP features in 27 patients with autoimmune pancreatitis

BACKGROUND: Autoimmune pancreatitis has been proposed as a new clinical entity. However, the ERCP features of this entity have not been well described. METHODS: Clinical and radiographic features in 27 patients with a diagnosis of autoimmune pancreatitis were evaluated. RESULTS: All 27 patients were at first suspected to have pancreatic cancer. The patients were predominantly elderly men and presented with jaundice or mild symptoms and pancreatic enlargement, but no attack of acute pancreatitis. A cholestatic biochemical profile and serum IgG elevation were usually present. A diffusely or segmentally irregular and narrow main pancreatic duct and a positive response to corticosteroid therapy were characteristic. During observation without treatment, serial pancreatography in 2 patients demonstrated progression of diffuse, irregular narrowing of the main pancreatic duct over periods, respectively, of 2 and 6 months. Both the irregular narrowing of the main pancreatic duct and distal bile duct strictures improved in various degrees in response to corticosteroid therapy. CONCLUSIONS: Segmental or diffuse irregular narrowing of the main pancreatic duct are ERCP features of autoimmune pancreatitis.     

Autoimmunpankreatitis

Autoimmune pancreatitis (AIP) has been established for more than 15?years as a disease entity of chronic pancreatitis. Although the autoimmune etiology is well established AIP is still an enigmatic disease. Morphological hallmarks of the disease are narrowing of the pancreatic duct system and frequently even narrowing of the bile duct by periductal lymphoplasmocytic inflammation. In cases of more localized inflammation obstructive jaundice due to a mass-forming lesion in the pancreatic head may mimic pancreatic ductal adenocarcinoma. Therefore, even in tertiary referral center, AIP patients underwent pancreatic surgery for suspected pancreatic cancer due to misclassification. Histopathologically, the disease can be differentiated into lymphoplasmacytic sclerosing pancreatitis (LPSP) with IgG4-positive cells or idiopathic ductocentral chronic pancreatitis (IDCP) with granulocyte epithelial lesions and eosinophils. Recently, LPSP has been coined AIP type 1 and IDCP as AIP type 2 following a recent consensus conference. Serologically, patients may present with elevated serum IgG and IgG4 levels. Additionally, autoantibodies have been described targeting ductal and acinar antigens. Association with other autoimmune manifestations in a wide range of organs is relatively frequent. In most cases, autoimmune pancreatitis responds to steroid treatment very quickly, which is of specific importance when considering the differential diagnosis of pancreatic cancer.     

Autoimmune Pankreatitis

Autoimmune pancreatitis has been established as a special entity of pancreatitis. It is an enigmatic disease since it is adding an autoimmune etiology to the existing causes of pancreatitis. Morphological hallmarks of the disease are narrowing of the pancreatic duct system and the bile duct by periductal lymphoplasmocytic inflammation. This results in many cases in obstructive jaundice due to a mass-forming lesion in the pancreatic head mimicking pancreatic ductal adenocarcinoma. Therefore, patients will frequently undergo surgery. Histopathologically, the disease can be diagnosed by IgG4-positive plasma cells. Serologically, patients may present with elevated serum IgG and IgG4 levels. Other autoantibodies are also described. Association with other autoimmune manifestations in a wide range of organs is frequent. Autoimmune pancreatitis will respond to steroid treatment, which is of specific importance because pancreatic cancer is one of its clinical differential diagnoses. It is important to positively diagnose autoimmune pancreatitis, especially if the bile ducts are affected, since cholangitis may be or become a prominent problem before or after surgery.     

Complete obstruction of the lower common bile duct caused by autoimmune pancreatitis: is biliary reconstruction really necessary?

Recent observations suggest that an immune response is involved in the development of chronic pancreatitis. We report a case of autoimmune pancreatitis in a patient who showed complete obstruction of the lower common bile duct. A 63‐year‐old man was admitted to a local hospital, complaining of appetite loss and back pain. The patient had obstructive jaundice, and percutaneous transhepatic gallbladder drainage was performed. Fluorography through the biliary drainage catheter showed complete obstruction of the lower common bile duct. The patient had no history of alcohol consumption and no family history of pancreatic disease. Physical examination revealed an elastic hard mass palpable in the upper abdomen. Abdominal ultrasound and abdominal computed tomography (CT) scans showed enlargement of the pancreas head. While autoimmune pancreatitis was highly likely, due to the patient's high serum immunoglobulin level, the possibility of carcinoma of the pancreas and/or lower common bile duct could not be ruled out. Laparotomy was performed, and wedge biopsy samples from the pancreas head and body revealed severe chronic pancreatitis with infiltration of reactive lymphocytes, a finding which was compatible with autoimmune pancreatitis. Cholecystectomy and biliary reconstruction, using choledochojejunostomy, were performed, because the complete bile duct obstruction was considered to be irreversible, due to severe fibrosis. After the operation, prednisolone (30 mg/day) was given orally for 1 month, and the entire pancreas regressed to a normal size. Complete obstruction of the common bile duct caused by autoimmune pancreatitis has not been reported previously; this phenomenon provides an insight into autoimmune pancreatitis and provokes a controversy regarding whether biliary reconstruction is needed for the treatment of complete biliary obstruction caused by autoimmune pancreatitis.     

Autoimmune pancreatitis, pancreatic mass, and lower gastrointestinal bleed.

Autoimmune pancreatitis (AIMP) is a recently described clinical entity causing chronic pancreatitis. It often presents with diffuse enlargement of the pancreas and/or a focal mass at the head of the pancreas causing common bile duct obstruction and jaundice. In most instances, AIMP is mistaken for pancreatic cancer. A number of laboratory abnormalities such as positive antinuclear antibody, hypergammaglobulinemia, and antibody to carbonic anhydrase are often present in these patients. Currently, pancreatic biopsy demonstrating characteristic histopathologic changes is essential to establish the diagnosis. We report the first case of AIMP presenting as a pancreatic tail mass and lower gastrointestinal bleed.     

Laparoscopic Pancreatic Biopsy in Autoimmune Pancreatitis—Report of TWO Cases

Two cases of autoimmune pancreatitis that were diagnosed by laparoscopic pancreatic biopsy are reported. Patient 1 was a 71–year-old woman with obstructive jaundice and dry eyes. Endoscopic retrograde cholangiopancreatography (ERCP) revealed stenosis of the distal common bile duct and proximal main pancreatic duct. Only the head of the pancreas was enlarged. The patient had associated Sjogren's syndrome and sclerosing cholangitis. Patient 2 was a 65–year-old man with obstructive jaundice that occurred after laparoscopic cholecystectomy. ERCP revealed a diffusely irregular and narrowed pancreatic duct and stenosis of the distal common bile duct. The whole pancreas was enlarged. Both patients underwent laparoscopic pancreatic biopsy to rule out pancreatic cancer. The definitive diagnosis in each case was autoimmune pancreatitis. The postoperative course in both cases was uneventful. Both patients recovered quickly with steroid therapy undertaken soon after the biopsy. In summary, a laparoscopic approach for the pancreatic biopsy in autoimmune pancreatitis appears to be feasible and useful in determining the therapeutic strategy. (Dig Endosc 1999; 11: 250–254)     

Inflammatory pseudotumor of the liver and peripheral eosinophilia in autoimmune pancreatitis

AIM: Inflammatory pseudotumor (IPT) of the liver is a rare benign lesion, the etiology of which remains obscure. It is not associated with any particular diseases apart from phlebitis and Crohn's disease. METHODS: A middle-aged male with hepatic IPT and peripheral eosinophilia associated with autoimmune pancreatitis (AIP) was selected for this study and review of literature. RESULTS: A 59-year-old male was admitted with obstructive jaundice, marked eosinophilia (1 343/mm3) and hypergammaglobulinemia (4 145 mg/dL). Imaging techniques revealed dilatation of the intrahepatic bile duct, stenosis of the common bile duct with diffuse wall thickening, gallbladder wall thickening, irregular narrowing of the pancreatic duct, and swelling of the pancreatic parenchyma. Multiple liver masses were also demonstrated and diagnosed as IPT by biopsy specimens. Six months later, the abnormal features of the biliary tree remarkably improved by the oral administration of prednisolone, and the liver masses disappeared. The swelling of the pancreatic head also improved. The peripheral eosinophil count normalized. IPT associated with AIP, as we know, has not been reported in the literature. The clinical features of the present case mimicked those of pancreatic cancer with liver metastasis. This case deserves to be documented to prevent misdiagnosis of similar cases.     

Segmental groove pancreatitis accompanied by protein plugs in Santorini's duct

"Groove pancreatitis", a form of segmental pancreatitis affecting the head of the pancreas, is local-ized within the "groove" between pancreas head, duo-denum, and common bile duct. Differentiation between groove pancreatitis and pancreatic head carcinoma is often difficult. We report a case of groove pancreatitis in which a hypoechoic mass between the duodenal wall and pancreas was clearly imaged, and narrowing of the second portion of the duodenum and bile duct stenosis were also found. The diagnosis was confirmed by surgery (pylorus-preserving pancreato duodenectomy). The patient was relieved from abdominal pain post operation. Up to the present, the patient has been good condition. We review the clinicopathologic and radiologic features of groove pancreatitis in the Japanese literature and discuss the possible role of Santorini's duct in its pathogenesis. We consider that impacted protein plugs in Santorini's duct are a pathogenic factor in the development of groove pancreatitis. Therefore, the findings of Santorini's duct on endoscopic retrograde pancreatography are very important in the diagnosis of groove pancreatitis. Groove pancreatitis presents various clinical features, such as biliary stenosis, duodenal stenosis, and pancreatic mass, and often masquerades as pancreatic head carcinoma. This condition should be kept in mind in the differential diagnosis of pancreatic head carcinoma. (Received Apr. 17, 1997; accepted Sept. 26, 1997)