
664 Practice of Oncology / Cancers of the Gastrointestinal Tract Evaluation and Assessing Resectability not add much additional value and are not routinely performed in the initial assessment for resectability. Although periampullary cancer (adenocarcinoma of the pan- Resection is attempted if (1) patients are medically fit for a pan- creas, ampulla of Vater, bile duct, or periampullary duode- createctomy, (2) there is no evidence of metastases, and (3) patients num) should be considered in any patient who presents with are believed to have resectable disease. Resectability is ultimately a conjugated hyperbilirubinemia, the likelihood is highest in decided by the operating surgeon, but general guidelines have been older patients (e.g., >55 years). In individuals with an expected proposed and are based on the likelihood of achieving a complete, pancreatic cancer, a thorough history and physical should be margin-negative resection.81,82 Resectability equates to a high prob- performed, followed by appropriate imaging for staging and to ability of an R0 resection; borderline resectability equates to a likely assess resectability. Critical findings on physical exam include result of an R1 resection (positive microscopic margins); and unre- scleral icterus, jaundice, and lymphadenopathy (e.g., Sister sectable (or locally advanced) PDA is likely to result in R2 resection Mary Joseph or Virchow nodes). A chest x-ray or chest CT (residual macroscopic disease). Resectable lesions do not invade the scan is performed to assess for pulmonary metastases and as a superior mesenteric artery (SMA), celiac axis (CA), common hepatic baseline study. Either a high-quality MRI or CT scan of the artery (CHA), or superior mesenteric–portal vein axis (SMV-PV). In abdomen is performed to evaluate the pancreas and measure contrast, locally advanced lesions encase (i.e., >180° invasion) any the extent of disease. We typically prefer CT for its superior of the previously mentioned arteries or occlude the SMV-PV such resolution and detailed depiction of the relevant vasculature. that no reconstructive options remain. Borderline resectable lesions Water is administered as oral contrast, and nonionic intrave- involve the visceral vessels to a lesser extent; they can abut the vis- nous contrast is rapidly injected. Slices are captured at 1-mm ceral arteries (<180° invasion), distort the visceral veins, or even oc- intervals from the diaphragm to the iliac crests at three different clude the SMV-PV, but with venous reconstruction still technically times or phases: early arterial, late arterial, and venous. Multi- feasible (Table 49.3).83 Most pancreatic surgeons offer patients with planar reformatting and three-dimensional (3D) surface render- resectable lesions an attempt at resection (although some centers ad- ing is performed during the early arterial and venous phases vocate neoadjvuant treatment prior to resection even for resectable (Fig. 49.4).80 Positron-emission tomography (PET)/CT scans do lesions84). Patients with locally advanced lesions are recommended A B C D Figure 49.4 Slices from a triphasic CT scan in a patient with resectable pancreatic cancer. (A) Late arterial phase. Double duct sign with dilated common bile and pancreatic ducts, and an atrophic pancreatic body. (B) Mass. (C) Coronal reconstructions, venous phase, with the mass apparent, and (D) clearly away from the superior mesenteric–portal vein axis (SMV/PV) axis. Yellow arrow = PDA; green arrow = common bile duct; red arrow = pancreatic duct; and blue arrow = SMV. (Courtesy of Jennifer Brumbaugh, Department of Surgery, Thomas Jefferson University.) tahir99 - UnitedVRG Chapter 49 Cancer of the Pancreas 665 TABLE 49.3 Criteria for Reseectability Resectable Borderline Resectable Locally Advanced Vessel R0 Resection Likely R1 Resection Likely R2 Resection Likely SMA No abutment Tumor abutment Tumor encasement Celiac axis/ No abutment Tumor abutment Tumor encasement hepatic artery SMV–PV Abutment may be Vein Distortion or short- Occluded and no present but no vein segment occlusion with suitable technical option for distortion vessel above and below reconstruction Note: R0 = gross total resection; histologically negative margins. R1 resection = gross total resection; one or more histologically positive margins. R2 resection = subtotal resection, visible tumor unresected. Abutment is ≤180° vessel circumference; encasement is >180° vessel circumference. SMA, superior mesenteric artery; SMV–PV, superior mesenteric vein–portal vein. Modified from Varadhachary GR, Tamm EP, Abbruzzese JL, et al. Borderline resectable pancreatic cancer: definitions, management, and role of preoperative therapy. Ann Surg Oncol 2006;13:1035–1046. to undergo palliative treatment without the intent to cure. Consider- pancreatic remnant is closed with suture (Fig. 49.5B) or staples. able debate remains for borderline PDAs; resection may be offered, A central pancreatectomy or local excision for a PDA is seldom if but increasingly, neoadjuvant treatment is recommended for even ever performed for PDA due to inadequate lymph node harvest. abutment or narrowing of the SMV-PV.81 Neoadjuvant chemo- A minimally invasive pancreatectomy using laparoscopy or a therapy (± radiation) can facilitate resection, and may improve the robotic-assisted approach may be safely performed. Although a likelihood of a complete resection with negative margins, even in minimally invasive approach is more common for benign and pre- the absence of a radiographic response.85 malignant lesions, a presumed diagnosis of PDA is not a contra- Obtaining a tissue diagnosis is not essential for all cases. Indica- indication.87 A meta-analysis comparing open versus laparoscopic tions include instances when (1) neoadjuvant treatment is advised distal pancreatectomies for PDA revealed similar oncologic and or (2) the pretest probability of an alternative diagnosis is consider- pathologic outcomes in the two groups. Patients undergoing lapa- able (e.g., suspicion for benign causes of pancreatitis, medically roscopy had a shorter postoperative stay by 4 days, less blood loss, OF ONCOLOGY PRACTICE managed neoplasms such as lymphoma, or a benign stricture). In and fewer surgical site infections.88 Importantly, studies compar- these instances, an EUS with fine-needle aspiration (FNA) biopsy ing the two techniques have not been prospective and random- is an effective method for obtaining tissue and has an accuracy in ized, and are, therefore, all subject to selection bias, with the more excess of 90%.86 When the diagnosis is clear based on imaging and difficult resections falling into the open group. Although most history, it is appropriate to proceed to attempted resection without high-volume pancreatic centers offer minimally invasive left-sided a preoperative tissue diagnosis. Similarly, placement of an endo- resections, laparoscopic PD is more technically challenging, and scopic biliary stent is frequently performed in jaundiced patients only a handful of centers have a significant experience.89 These preoperatively, but is essential in only selected cases. A multicenter centers report comparable outcomes with minimally invasive ver- prospective and randomized trial compared routine preoperative sus open pancreatic surgery in their own experience, although an biliary drainage with delayed resection to early surgery without advantage of laparoscopic PD has not yet been proven in a pro- stenting in jaundiced patients with pancreatic cancer. Serious spective and randomized study. complications were increased nearly twofold in the routine bili- ary drainage group (74% versus 39%; p <0.001), suggesting that International Study Group of Pancreatic biliary decompression be reserved for jaundiced patients unable Surgery Contributions to undergo resection in a short-time frame (1 to 2 weeks).86 A pan- creaticoduodenectomy is safely performed, even when the total Surgically related mortality after PD has improved dramatically bilirubin is markedly elevated. Patients, who are otherwise healthy, over the last 3 decades, and is lower than 5% at most high volume with normal renal function and clotting parameters will usually centers.27 However, morbidity remains high (∼40%). The most tolerate a safely performed pancreaticoduodenectomy with a total common complications include pancreatic leak (20%), delayed bilirubin as high as 20 mg/dL. gastric emptying (15%), and wound infection (10%). Bile and duodenal leaks occur in roughly 3% and 1% of patients, respec- Surgery tively.27 The greatest limitation to studies focused on pancreatec- tomy-related complications has been a lack of standard definitions Technical aspects of a pancreatectomy are detailed elsewhere across institutions, making comparisons between institutions’ re- and are well beyond the scope of this chapter, hence will only ports difficult. The formation of an International Study Group of be reviewed briefly here. For right-sided pancreatic cancers, a Pancreatic Surgery (ISGPS) to address this issue has been a great pancreaticoduodenectomy (PD) is performed. The specimen advance in pancreatic surgery–related outcomes research. The includes the gallbladder, duodenum, head of the pancreas (the group has published consensus criteria and definitions for com- pancreatic transection typically is at the level of the neck), proxi- plication grading on the following pancreatic-specific morbidities: mal jejunum, and distal common bile duct. The most proximal postoperative pancreatic fistula (leak),90 delayed gastric
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