Inmedicine, apancreatectomy is thesurgical removal of all or part of thepancreas. Several types of pancreatectomies exist, includingpancreaticoduodenectomy (Whipple procedure), distal pancreatectomy, segmental pancreatectomy, and total pancreatectomy.
Pancreatic surgeries have been reported as early as the 1800s,[1][2] however the first successful complete pancreatectomy was reported in 1944.[3] Surgery on the pancreas is complex, at times requiring both theresection, or removal of parts or the entire organ, as well asanastomosis, or the connection of different parts of the digestive system. Advances in technology have allowed for the improvement in outcomes, reduction of complications, and improvement in surgical techniques.[1][4]
The pancreas is adigestive andendocrine organ that serves as agland. It releases endocrine and exocrine hormones to help with metabolism and digestion.[5]
The pancreas is located behind the stomach. It is divided into the head, neck, body and tail. Some people have a fifth part of the pancreas known as the uncinate process.[6] The pancreas contains a main pancreatic duct where the exocrine molecules collect and then drain into theduodenum via thecommon bile duct. There is also an accessory pancreatic duct that drains above the main duct straight into the duodenum.
Blood supply to the pancreas comes from theceliac artery and thesuperior mesenteric artery, branches of the aorta.[6]
The pancreas releasesdigestive enzymes into the gastrointestinal tract via the pancreatic ducts. These enzymes make it possible to break down food and materials in the small intestine allowing nutritional molecules to be absorbed. The enzymes includetrypsin and chymotrypsin which help digest proteins,amylase which breaks down carbohydrates, as well aslipase which breaks down fats. The pancreas has majority exocrine function.[6]
The pancreas is also made up of areas of cells known aspancreatic islets which include alpha, beta, and delta cells.Alpha cells secreteglucagon,beta cells secreteinsulin, anddelta cells secretesomatostatin, all of which are important hormones for metabolism. The endocrine function of the pancreatic glands is only 1-2% of pancreatic function.[6]
Pancreatectomies may be performed for a variety of reasons, including:
| Pancreatectomy | |
|---|---|
_CRUK_287.svg) Diagram showing the area removed for a total pancreatectomy | |
| ICD-9-CM | 52.5-52.6 |
| MeSH | D010180 |
| OPS-301 code | 5-524-5-525 |
The most common surgical procedure involving removal of a portion of the pancreas is called apancreaticoduodenectomy.
Adistal pancreatectomy is removal of the body and/or tail of the pancreas. It is considered the standard procedure for cancer lesions found in the body or tail of the pancreas.[2][6][7] The surgery is considered safe, with low morbidity and mortality, with the exception of in the case of pancreatic adenocarcinomas, a type of cancer that has a poorprognosis.[2] Both open andlaparoscopic techniques have been used for this type of surgery.[2] Robot-assisted pancreatectomy also offers benefits in the morbidity and mortality.[1]
Asegmental pancreatectomy is used to remove part of the pancreas so that there is not an excess of loss of pancreatic tissue. It is used in instances pfbenign orlow-grade tumors of the pancreatic neck and body.[8] A study by Du et. al. published in 2013 showed decreased intraoperativehemorrhage and risk of post-operative diabetes, however, there was an increase in pancreatic fistula rate in patients that underwent a middle segmental pancreatectomy.[8]
Atotal pancreatectomy is the complete removal of the pancreas. It is a surgery used to remove the entire pancreas for issues such as chronic pancreatitis or advanced pancreatic cancers if non-surgical techniques do not work. This surgery is known to have disadvantages, however, over the years, surgical techniques as well as the surgical outcomes have improved.[9] Total removal of the pancreas can lead to an insufficiency of hormones produced.
In total pancreatectomy, thegallbladder, distalstomach, a portion of thesmall intestine, associatedlymph nodes and in certain cases thespleen are removed in addition to the entire pancreas.[10]
TP-IAT (total pancreatectomy withislet autotransplantation[11][12]) has also gained respectable traction within the medical community. These procedures are used in the management of several conditions involving the pancreas, such as benignpancreatic tumors,pancreatic cancer, andpancreatitis. TP-IAT is used to prevent post-operative diabetes and the subsequent complications.[13] The islet cells are isolated from the explanted pancreas into the portal vein in order to help mitigate the loss of endocrine function following total pancreatectomy.[14][15]
Reasons why patients should not receive a specific treatment to the disease/illness are known ascontraindications. Contraindications to pancreatectomies include a patient's other medical history orcomorbidities, poor functional status of the patient, and/or bleeding issues. Contraindications to pancreatectomy also can vary by type. In distal pancreatectomies, lesions that are not fully able to be removed are considered contraindications.[6]
Among the common complications of complete or nearly complete pancreatectomy are deficiencies of pancreatic endocrine or exocrine function, requiring replacement ofinsulin ordigestive enzymes. Patients can developtype 1 diabetes[16] after pancreatectomy and a study by Kim et al. determined that patients with BMIs >25 kg/m2 had higher incidences of pancreatic diabetes after distal pancreatectomy.[7] Type 1 diabetes can be treated with careful blood glucose monitoring and insulin therapy.
Complications also includefistulas, or the formation of an abnormal connection between two organs, and pancreatic leakage, where digestive enzymes can leak through the formation of the fistulas.[3] Treatment for pancreatic leaks after surgery can includestenting and occlusion of the pancreatic duct, the use ofoctreotide, a drug that mimics somatostatin which inhibits secretion from the pancreas, or two other types of surgeries that remove part of the stomach or small intestine along with the pancreas.[3]
After a total pancreatectomy, the body no longer produces its owninsulin orpancreatic enzymes, so patients have to take insulin and enzyme supplements. Those who were not already diabetic become so (type 3c diabetes).[13]Glycemic control is challenging even for relatively young and healthy apancreatic people, owing to thedigestive challenges of not having endogenous insulin and pancreatic enzymes underautonomic control. It can be challenging depending on age and comorbidities. But overall, quality of life in patients after total pancreatectomy is comparable with quality of life in patients who undergo a partial pancreatic resection.[17]