Pancreatosplenectomy and Spleen-Preserving Distal Pancreatectomy

Background

Pancreatosplenectomy (pancreaticosplenectomy) or spleen-preserving distal pancreatectomy is performed to surgically treat pancreatic disease of the tail and body. Distal pancreatectomy involves surgical resection of the body and tail of the pancreas to the left of the superior mesenteric vein (SMV)–portal vein confluence, [1 with or without splenectomy.

The choice of procedure depends upon the disease process, the characteristics of the lesion, and the surgeon's experience. Spleen-preserving distal pancreatectomy is reserved for chronic pancreatitis, proven benign pancreatic lesions and cysts, neuroendocrine tumors, and trauma.

Lesions in the body and tail of the pancreas become symptomatic as they enlarge and invade surrounding structures. However, with the increasing use of imaging studies, more incidental pancreatic lesions are discovered and diagnosed. Smaller lesions diagnosed at earlier stages are more amenable to surgical treatment.

Indications

Pancreatic neoplasms

Adenocarcinomas of the distal pancreas account for 15-25% of pancreatic adenocarcinomas. [2 Distal pancreatosplenectomy with lymphadenectomy is indicated for adenocarcinoma that is locally resectable without distant metastasis. Spleen-preserving distal pancreatectomy is contraindicated for malignant lesions of the distal pancreas.

Neuroendocrine tumors represent 2-4% of pancreatic tumors. [2 All neuroendocrine tumors have malignant potential and should be resected with curative intent.

Solid pseudopapillary tumors are evenly distributed throughout the pancreas, with 46-67% present in the body and tail. These tumors represent 0.9-2.5% of solid pancreatic tumors, with 82-93% of cases diagnosed in young women. [2 Attempts should be made for curative resection unless other contraindications are present.

Chronic pancreatitis

Chronic pancreatitis is defined as chronic and recurrent inflammation of the pancreas. [3 Surgery is indicated for pain, pseudocysts, suspicion of malignancy, stenosis of the middle to distal pancreatic duct, pancreatolithiasis, and stenosis of the celiac or mesenteric vessels. Intractable pain is the most common indication for distal pancreatectomy in chronic pancreatitis, with relief of symptoms in 31-90% patients. [34]

Pancreatic cysts

Serous cystadenomas are typically benign and represent 20-40% of cystic pancreatic tumors. [5 Mucinous tumors have malignant potential and account for 20-40% of cystic tumors. [5 Resection is indicated in symptomatic enlarging cysts greater than 2 cm. Intraductal papillary mucinous tumor is believed to follow the adenoma carcinoma sequence and should be resected with curative intent.

Because of their similarities in appearance on diagnostic imaging, pancreatic pseudocysts and cystic tumors may be distinguished by means of endoscopic ultrasonography (US) with fine-needle aspiration (FNA). Findings suggestive of malignancy include mucin, mucin-secreting cells, or a high carcinoembryonic antigen (CEA) level. [5]

Symptomatic or enlarging pancreatic pseudocysts can be treated with distal pancreatectomy after the acute pancreatitis episode has resolved. However, pseudocysts are best treated with internal drainage procedures as opposed to resection.

Contraindications

Contraindications for distal pancreatosplenectomy and spleen-preserving distal pancreatectomy include the following:

  • Metastatic disease
  • Peritoneal carcinosis
  • Vascular invasion
  • Pancreatitis involving the entire pancreas

Technical Considerations

Anatomy

The pancreas, from Greek pan- ("all") and kreas ("flesh"), is a 12- to 15-cm-long J-shaped (like a hockey stick), soft, lobulated, retroperitoneal organ. It lies transversely, though a bit obliquely, on the posterior abdominal wall behind the stomach, across the lumbar (L1-2) spine (see the image below).

Pancreas anatomy. Pancreas anatomy.

The head of the pancreas lies in the duodenal C loop in front of the inferior vena cava (IVC) and the left renal vein. The body and tail of the pancreas run obliquely upward to the left in front of the aorta and left kidney. The pancreatic neck is the arbitrary junction between the head and body of the pancreas. The narrow tip of the tail of the pancreas reaches the splenic hilum in the splenorenal (lienorenal) ligament.

For more information about the relevant anatomy, see Pancreas Anatomy.

Procedural planning

About 50% of patients with adenocarcinoma have unresectable disease, and 35% have distant metastasis at the time of diagnosis. [6Therefore, staging laparoscopy is recommended prior to resection. Major vasculature involvement with the celiac root, peritoneal disease, and metastasis to the liver are contraindications for resection. [6]

No consensus has been reached regarding whether a laparoscopic or open distal pancreatectomy should be performed. [78Laparoscopic distal pancreatectomy has advantages similar to other laparoscopic procedures, such as decreased length of stay, decreased intraoperative blood loss, and fewer postoperative complications. [910(See Outcomes.) However, its applicability in the setting of malignancy requires further study. [11]

Complication prevention

When a splenectomy is planned with a distal pancreatectomy, meningococcal, pneumococcal, and Haemophilus influenzae type B vaccines should be given, ideally 2 weeks prior to the planned resection. Antibiotics, such as a second- or third-generation cephalosporin, should be administered 30 minutes prior to incision.

Outcomes

Multiple meta-analyses have demonstrated laparoscopic distal pancreatectomy to be safe with improved postoperative outcomes compared to open resection. [12 Jin et al found laparoscopic distal pancreatectomy to be associated with fewer blood transfusions, decreased blood loss, earlier oral intake, and fewer surgical site infections (SSIs). [13 There was no difference found in operative time or incidence of pancreatic fistula.

In a retrospective review by Kooby et al, [9 short-term oncologic outcomes (node harvest, margin status) and long-term oncologic outcomes (survival) were comparable in open and laparoscopic distal pancreatectomy.

A review article by Borja-Cacho et al [14 concluded that laparoscopic distal pancreatectomy had a similar morbidity to open pancreatectomy, but had a decreased length of stay. This study concluded that laparoscopic distal pancreatectomy is a safe procedure that is appropriately used for benign pancreatic disease. A randomized, prospective multicenter trial is required for further comparison to determine if laparoscopic distal pancreatectomy is appropriate in malignant pancreatic lesions.

In a randomized trial by Nigri et al, [15 the conversion rate for laparoscopic to a hand-assisted technique was 37%. The conversion rate for laparoscopic to open was 11%. Reasons for conversion include multiple intra-abdominal adhesions and hemorrhage.

Several studies have examined the feasibility of robotic distal pancreatectomy. Robotics have the benefit of three-dimensional (3D) visualization, and improved ergonomics to allow for fine dissection. The safety profile is similar to that for laparoscopic procedures; however, robotic distal pancreatectomy has been associated with increased cost and operating times. Due to the varying outcomes in negative margins and lymph node yield, no consensus has been reached on the oncologic appropriateness of robotic distal pancreatectomy in malignancy. [1617]

Murakawa et al evaluated short- and long-term outcomes in 49 consecutive patients who underwent radical antegrade modular pancreatosplenectomy (RAMPS; see Technique) for pancreatic cancer. [18 They reported a median operating time of 278 minutes (range, 140-625), a median intraoperative blood loss of 850 mL (range, 60-2790), an overall morbidity of 51.4%, and a mortality of 0%. After follow-up (median, 41.1 months), the 1-year overall survival rate was 84.1% and the 3-year overall rate was 38.6%. Median overall survival was 22.6 months.

Abe et al studied 93 patients who underwent treatment of pancreas body and tail adenocarcinoma, comparing the results of standard retrograde pancreatosplenectomy (n = 40) with those of RAMPS (n = 53). [19In the RAMPS group, more lymph nodes were retrieved (28.4 ± 11.6 vs 20.7 ± 10.1), R0 resection was more frequent (90.5% vs 67.5%), there was less intraoperative bleeding (485.4 ± 63.3 mL vs 682.3 ± 72.8 mL), and operating time was shorter (267.3 ± 11.5 min vs 339.4 ± 13.2 min). 

Equipment

Preoperative placement of invasive monitors, such as an arterial line and a central venous line, should be considered and used in accordance with the patient’s clinical picture.

A standard general surgery open tray can be used. A gastrointestinal anastomosis (GIA) stapler, surgical clips, an ultrasonic scalpel, and vascular clamps should also be available in the event of vascular injury.

Various techniques for transecting the pancreas are described (see Technique). The appropriate instruments for a giving approach should be available, according to the surgeon's preference and experience.

Patient Preparation

This procedure is completed with the patient under general endotracheal anesthesia.

After anesthesia is induced, the patient is placed on the table in a supine position with the arms extended or in a modified right lateral decubitus position with the arms tucked. For the open approach, a midline, left subcostal, or bilateral subcostal incision allows adequate exposure. Trocar placement for laparoscopic distal pancreatectomy is discussed elsewhere (see Technique).

Monitoring & Follow-up

If stable, patients can be sent to a surgical floor in the immediate postoperative period. Unstable patients should be admitted to the intensive care unit (ICU) for further resuscitation and monitoring. A diet can be started as early as postoperative day 1 and advanced as tolerated to a diabetic diet.

Drain output should be recorded daily and monitored for increases in output and changes in color as the diet is advanced. A drain amylase level should be checked prior to discharge with a cutoff value of greater than 5000 U/L of amylase for removal or continuation. If a fistula is suspected and adequately drained, the drain should remain until the fistula resolves.

Pancreatic fistulas can form along the track of the previous drain, and should be managed conservatively. Fistula was defined by the International Study Group of Pancreatic Fistula as “output via an operatively placed drain of any measurable volume of drain fluid on or after postoperative day 3 with amylase content greater than three times the upper normal serum value.” [14]

The drain is removed once the output has decreased. Fistulas typically heal spontaneously, but output can be controlled with a low-fat diet, somatostatin analogues, and octreotide. Persistent fistulas may require a pancreatic duct stent, total parenteral nutrition (TPN), and bowel rest.

In the immediate postoperative period, patients should be monitored with sliding scale insulin and tight glucose control. Patients are at risk for developing diabetes, and blood glucose should be monitored with subsequent follow-up. Malabsorption from deficiency of the exocrine pancreas can occur and should be treated with pancreatic replacement enzymes and diet modification. Patients with malignant tumors should have interval follow-up in 3-6 months with serial imaging to evaluate for disease recurrence.

Technique

Updated: Nov 20, 2018 
  • Author: Camille Blackledge, MD; Chief Editor: Kurt E Roberts, MD  more...
      
SECTIONS

Open Retrograde Distal Pancreatosplenectomy

Staging laparotomy should be performed before resection. The peritoneum, omentum, mesentery, and viscera should be visually inspected and palpated for signs of peritoneal or metastatic disease.

Once the abdomen is entered, the lesser omentum can be accessed by dividing the gastrocolic ligament below the gastroepiploic vessels. The short gastric vessels are ligated to expose the body and tail of the pancreas. [20(See the image below.)

Ligated tail of the pancreas. Ligated tail of the pancreas.

The spleen is mobilized by dividing the splenorenal and splenophrenic ligaments. The remaining short gastric vessels at the upper pole of the spleen should be divided.

The peritoneal reflection covering the pancreas is divided with Metzenbaum scissors or electrocautery. Sharp dissection behind the pancreas frees it from the retroperitoneal space, and care should be taken to remain in the plane between the kidneys and pancreas, leaving Gerota’s fascia intact. As the spleen is retracted medially with the tail of the pancreas, small perforating vessels are ligated and divided. This maneuver allows direct visualization of the posterior aspect of the pancreas. (See the image below.)

Ligated vessels of the pancreas. Ligated vessels of the pancreas.

The splenic artery, located superiorly, should be clearly identified and ligated at its origin. The splenic artery should be ligated first to avoid splenic congestion. The confluence of the splenic vein and the superior mesenteric vein (SMV), posteriorly, should be dissected, and the splenic vein should be ligated and divided at its origin. (See the image below.)

Remaining pancreas. Remaining pancreas.

The pancreas can then be divided with either the electrocautery or a gastrointestinal anastomosis (GIA) stapler. The pancreatic duct should be identified and suture-ligated with 3-0 silk sutures. Horizontal mattress, figure-eight, or a continuous running suture can all be used as methods to close the pancreatic remnant. A Jackson-Pratt drain is placed near the transected end of the pancreatic remnant and brought out through a separate incision. The abdomen is closed with a 1-0 polydioxanone suture and staples on the skin.

Radical Antegrade Modular Pancreatosplenectomy

Radical antegrade modular pancreatosplenectomy (RAMPS) [21 was described by Strasberg et al [22 as an approach to distal pancreatectomy that allows better oncologic resection with lymphadenectomy. If there is extensive tumor involvement, this resection allows en-bloc removal of the pancreas and all involved tissue.

The lesser sac is entered as previously described for open retrograde distal pancreatosplenectomy, and the dissection is carried to the origin of the right gastroepiploic artery.

From the inferior border, the pancreatic neck is dissected off of the SMV and the portal vein. [1 The middle colic vein may be ligated if necessary to facilitate exposure. The hepatic artery should be identified at the superior border of the pancreas. The hepatic artery is traced to identify the lymph nodes on the hepatic artery proper and the portal vein, which are mobilized. Ligating the gastroduodenal artery reveals the anterior surface of the portal vein and allows its complete dissection away from the pancreatic neck.

The neck is then transected with either a GIA stapler or an electrocautery. The splenic artery and vein are then ligated and divided at their respective origins.

Depending on the extent of tumor involvement, dissection is extended posteriorly to include retroperitoneal tissue and lymphatics anterior to the left renal vein and adrenal gland. Careful vertical dissection should reveal the entry of the superior mesenteric artery (SMA) into the aorta, which should fall within the boundaries of the lymphadenectomy. Lymph nodes should be taken in the area to the left of the SMA, bounded superiorly and inferiorly by the celiac artery and SMA and posteriorly by the aorta.

The spleen is mobilized by dividing the splenorenal and splenophrenic attachments. An R0 resection may require en-bloc removal of the left adrenal gland and kidney, the transverse colon, the stomach, the duodenum, and the jejunum. [6]

A drain is left adjacent to the pancreatic bed.

Spleen-Preserving Distal Pancreatectomy

The approach for spleen-preserving distal pancreatectomy is similar to that described for RAMPS. Despite the increase in time due to the difficulty with dissection, preserving the spleen has the additional benefit of preserving hematologic and immunologic function. It has been shown to be safe when compared to distal pancreatosplenectomy. [2324]

The lesser sac is entered as previously described for open retrograde distal pancreatosplenectomy, and the dissection is carried to the origin of the right gastroepiploic artery.

From the inferior border, the pancreatic neck is dissected off of the SMV and the portal vein. [1 The middle colic vein may be ligated if necessary to facilitate exposure. The hepatic artery should be identified at the superior border of the pancreas. The hepatic artery is traced to identify the lymph nodes on the hepatic artery proper and portal vein, which are mobilized. Ligating the gastroduodenal artery reveals the anterior surface of the portal vein and allows its complete dissection away from the pancreatic neck.

The splenic artery and vein are carefully dissected from the posterior surface of the pancreas. Vascular control with vessel loops or a Penrose drain can be used for retraction or in the event of vascular injury and hemorrhage. The pancreas is then divided and rotated laterally. As the pancreas is gently elevated, short branches of the splenic artery and vein are ligated with surgical ties or clips and then cut.

The dissection is carried out from medial to lateral in the direction of the splenic hilum. Once all pancreatic branches to the splenic vein have been ligated and divided, the pancreatic tail is removed.

The pancreatic stump is then treated according to the surgeon's preference, and a drain is left near the pancreatic remnant.

Questions have been raised regarding whether it is preferable to preserve or ligate the splenic vessels in a spleen-preserving distal pancreatectomy. Some analyses have suggested that splenic vessel preservation is associated with lower complication rates [2526; however, the available data are limited, and further studies are warranted.

Laparoscopic Distal Pancreatectomy

The patient should be placed supine or in a modified lithotomy position with the left side elevated.

The first trocar should be a 10-mm supraumbilical port just to the left of the midline. The abdomen is insufflated, and subsequent trocars are placed under direct visualization by using a 10-mm 30º laparoscope. A staging laparoscopy is performed by inspecting peritoneal surfaces, the omentum, mesentery, and all viscera. [22]

A second 10- to 12-mm trocar is placed in the left midclavicular line. A 5-mm trocar is then placed in the midepigastric/subxiphoid area. The fourth trocar is placed in the left anterior axillary line. [27]

The lesser omentum is entered by dividing the transverse mesocolon toward the spleen. As the stomach is retracted cephalad, attachments to the pancreas should be divided. The dissection is continued medially along the inferior aspect of the gastroepiploic vessels.

The spleen is mobilized by dividing the splenocolic ligament. The short gastric vessels are ligated and divided with an ultrasonic scalpel, a coagulator, or clips.

The pancreas should be dissected at the superior border to identify the splenic artery. At this point, if dissection is adequate, the splenic artery can be ligated and divided. The splenic artery and vein are dissected away from the posterior border to allow retraction of the pancreas.

An endoscopic GIA stapler is used to divide the pancreas. If this was not previously done, the splenic artery is identified and transected using a vascular load. As the pancreas is retracted laterally, the splenic vein is divided in a similar manner. The pancreas can also be transected as a unit with the artery and vein. [27 The remaining splenic attachments are divided to facilitate removal. The midline incision is extended, and the specimen is removed in an endoscopic retrieval pouch.

If the spleen is to be preserved, the splenic vessels may be either ligated or preserved. A study by Worhunsky et al did not find either approach to be clearly superior with regard to outcome and splenic preservation and concluded that the choice should be based on technical considerations, including location in the pancreas. [28]

A dual-incision approach to laparoscopic spleen-preserving distal pancreatectomy has been described that uses fewer trocars. Kim et al assessed the safety and feasibility of this approach (n = 22) versus conventional laparoscopic spleen-preserving distal pancreatectomy (n = 26) and reported significantly shorter operating times and reduced blood loss in the dual-incision group, as well as more successful preservation of splenic vessels. [29]

Robot-assisted approaches to pancreatoduodenectomy and distal pancreatectomy have been described that appear comparable to conventional laparoscopic approaches in terms of perioperative outcomes; however, there is a need for further randomized controlled trials to achieve a clearer determination of the clinical safety and efficacy of these approaches. [3031]

Resection and Closure of Pancreatic Stump

Various techniques have been described for resection of the pancreas and treatment of the pancreatic remnant. These techniques have included pancreatic duct ligation, transaction with linear stapling devices, enteric drainage, sealing with fibrin glue, enteric drainage, transection with an ultrasonic coagulator, pancreaticojejunal anastomosis, gastric or jejunal seromuscular patch, and prolamine injection. [32]

These methods have all been attempted in an effort to decrease the risk of postoperative pancreatic duct leak and fistula formation. Studies have been unsuccessful in attempts to find one method superior. However, the most commonly used methods are linear staple transection and pancreatic transection with ligation of the pancreatic duct and closure of the remaining stump.

Complications

Risk factors associated with increased mortality include the following [33:

  • Male sex
  • Obesity
  • Smoking
  • Steroid use
  • Neurologic disease
  • Abnormal platelet count
  • Elevated creatinine

Other complications include pancreatic leak, pancreatic fistula (2-24%), intra-abdominal abscess (1-12%), new-onset insulin-dependent diabetes, hemorrhage, small-bowel obstructionsepsis, and surgical-site infection (SSI). [634]

The American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) found sepsis to be the most common complication (8.7%), followed by SSI (5.9%), and pneumonia. In a multivariate analysis of distal pancreatectomy by Kelly et al, [34 the 30-day complication rate was 28.1%, mortality was 1.2%, and serious complications occurred in 22.2% of cases.

Risk factors for pancreatic fistula include the following [35:

Methods to decrease pancreatic leaks and fistulas have been investigated, such as fibrin glue on the transected pancreas, somatostatin, and octreotide, but no method has been established as clearly superior. However, a Cochrane Review demonstrated an overall 34% decreased incidence of pancreatic leak with the use of somatostatin analogues. This best evidence paper recommended the use of somatostatin analogues in the postoperative period for patients undergoing pancreatic resection. [36]

Literature suggests that using a stapler to transect the pancreas can decrease pancreatic leak and fistula rates, but more investigations are needed before a definitive conclusion can be drawn. Drain placement is recommended to help identify and control pancreatic leaks.