What Is Pancreatic Ductal Carcinoma?

Intraductal papillary mucinous neoplasm (IPMN) in the pancreatic duct is a rare pancreatic cystic tumor. Due to insufficient understanding of it, it has often been diagnosed as chronic pancreatitis or mucinous cystadenomas in the past. IPMN and IPMT (Intraductal papillary mucinous tumor) is the title of the same disease.

Intraductal papillary myxoma

Intraductal papillary mucinous neoplasm (IPMN) in the pancreatic duct is a rare pancreatic cystic tumor. Due to insufficient understanding of it, it has often been diagnosed as chronic pancreatitis or mucinous cystadenomas in the past. IPMN and IPMT (Intraductal papillary mucinous tumor) is the title of the same disease.

It originates from the ductal epithelium of the pancreas, grows like a papilla, secretes too much mucus, and causes the main pancreatic duct and / or branch pancreatic duct to expand or cystic.

IPMN occurs predominantly in the elderly, and is most commonly seen between 6o and 7o years old, with a male to female ratio of about 2: 1. Clinical signs and symptoms depend on the extent of catheter dilation and the amount of mucus produced. It can manifest as upper abdominal pain and fatigue, and can also cause clinical manifestations of chronic pancreatitis and even acute attacks due to obstruction of pancreatic juice outflow.

The tumor can grow locally or spread along the main pancreatic duct or branch pancreatic duct, leading to the progressive expansion of the adjacent main pancreatic duct or branch pancreatic duct. A large amount of mucus is secreted in the dilated duct, and tumors located in the pancreatic head and the uncinate area can protrude into the duodenum, allowing the mucus to flow from the enlarged duodenal papilla into the intestinal cavity. Under the microscope, there are countless small nipples in the tumor. The surface is covered with columnar epithelium, and the degree of epithelial differentiation varies widely. It can be from atypical hyperplasia to papillary adenoma or adenocarcinoma, or it can be mixed. Therefore, some scholars also use ipmt to refer to IPMN for malignant or potentially malignant tumors.

nickname

Chronic pancreatitis or myxoid cystadenoma.

English name

IPMN and IPMT

Common locations

Tumors in the head of the pancreas and the uncinate area can penetrate into the duodenum

Common symptoms

Causes pancreatitis, making it difficult to distinguish it from pancreatic duct dilatation and pseudocyst formation caused by chronic pancreatitis

It originates from the ductal epithelium of the pancreas, grows like a papilla, secretes too much mucus, and causes the main pancreatic duct and / or branch pancreatic duct to expand or cystic.

Ipmn can be divided into 3 types according to different origins, and the main pancreatic duct type is relatively rare, divided into 2 subtypes of segmental type and diffuse type. Those in the head of the pancreas are mostly diffuse due to mucus obstruction; those in the body and tail of the pancreas are mostly segmental.

CT and MRI (including MRCP) show moderate to significant dilatation of the main pancreatic duct, duodenal papillae can enlarge and protrude into the intestinal cavity, and the nipple protrusions on the pancreatic duct wall are small and flat and difficult to show. Branched pancreatic ducts occur in the pancreatic uncinate process and can also be located at the tail of the body. CT and mri mainly manifest as lobular or grape-like cystic lesions, which are aggregated from smaller cystic lesions and have traffic. Fusion into a single large cyst-like mass, papillary protrusions <3 mm are difficult to show. The main pancreatic duct may be slightly dilated or accompanied by pancreatic atrophy. Multi-dimensional reconstruction of MRCP can more vividly display the characteristics of cystic lesions. The mixed type is the pancreatic duct branching of the pancreas and the main pancreatic duct. It can also be a combination of the body and tail branch pancreatic duct and main pancreatic duct expansion. If solid nodules> 10 mm in the tumor, main pancreatic duct dilatation> 10mm, diffuse or polycentric origin, intramural calcification, and clinical symptoms of diabetes should be highly vigilant, suggesting malignant IPMN.

IPMN should be distinguished from other pancreatic cystic lesions. Ipmn can cause pancreatitis manifestations, making it difficult to distinguish it from pancreatic duct dilatation and pseudocyst formation caused by chronic pancreatitis. The presence of wall nodules and papillary human duodenal cavities is helpful for the diagnosis of ipmt, and Chronic pancreatitis caused a dilated pancreatic duct with bead-like formation and gross calcification, which is rare in IPMN.

Although pancreatic ductal cancer necrotic cysts can also appear as cystic tumors, solid components can still be seen around them. In addition, characteristics such as easy to invade the main blood vessels around the pancreas and the growth of eosinophils are significantly different from IPMN and easy to identify.

Mucosal cystic tumors can also see wall nodules and separations, but most of them are located at the tail of the body. Middle-aged women are more likely to have a single large sac or several large sacs to form a round or oval-shaped mass, without the main Pancreatic duct dilatation. IPMN is more common in elderly men. It is mostly located in the pancreatic axillary process, and the main pancreatic duct is dilated to different degrees. It is not difficult to distinguish between the two. Although serous cystadenoma can also present with multiple microcapsule-like manifestations, its young age and stellate fibrous scar and radial calcification can be seen in the center, which can be distinguished from IPMN.

For branched ipmn that is isolated from the pancreatic uncinate process and the tumor diameter is less than 2.5 cm, it can be closely observed clinically. For other types of IPMN, due to their potentially malignant characteristics, they should be actively surgically removed, which is more effective than pancreatic head cancer. And ampulla cancer is good.