Faculty Bibliography

BACKGROUND:Positron emission tomography (PET) as an adjunct to conventional imaging in the staging of pancreatic adenocarcinoma is controversial. Herein, we assess the utility of PET in identifying metastatic disease and evaluate the prognostic potential of standard uptake value (SUV). METHODS:Imaging and follow-up data for patients diagnosed with pancreatic adenocarcinoma were reviewed retrospectively. Resectability was assessed based on established criteria, and sensitivity, specificity, and accuracy of PET were compared to those of conventional imaging modalities. RESULTS:For 123 patients evaluated 2005-2011, PET and CT/MRI were concordant in 108 (88 %) cases; however, PET identified occult metastatic lesions in seven (5.6 %). False-positive PETs delayed surgery for three (8.3 %) patients. In a cohort free of metastatic disease in 78.9 % of cases, the sensitivity and specificity of PET for metastases were 89.3 and 85.1 %, respectively, compared with 62.5 and 93.5 % for CT and 61.5 and 100.0 % for MRI. Positive predictive value and negative predictive value of PET were 64.1 and 96.4 %, respectively, compared with 75.0 and 88.9 % for CT and 100.0 and 91.9 % for MRI. Average difference in maximum SUV of resectable and unresectable lesions was not statistically significant (5.65 vs. 6.5, p = 0.224) nor was maximum SUV a statistically significant predictor of survival (p = 0.18). CONCLUSION/CONCLUSIONS:PET is more sensitive in identifying metastatic lesions than CT or MRI; however, it has a lower specificity, lower positive predictive value, and in some cases, can delay definitive surgical management. Therefore, PET has limited utility as an adjunctive modality in staging of pancreatic adenocarcinoma.

BACKGROUND:Laparoscopic retroperitoneal (RP) adrenalectomy has gained popularity as the preferred approach over transabdominal (TA) method; however, surgeons have been reluctant to offer this operation to obese patients because of the concerns over inadequate working space and overall perceived higher rate of complications. The aim of the present study was to evaluate the feasibility and safety of RP adrenalectomy compared with TA adrenalectomy, specifically in morbidly obese patients. METHODS:All laparoscopic adrenalectomies performed at our institution between 2004 and 2012 were reviewed retrospectively. Presenting features, operative characteristics, and postoperative outcomes were evaluated. Complications were graded using Clavien system. Continuous variables were compared using Student t-test. Categorical variables were compared using χ(2)-test. Prediction models were constructed using linear or logistic regression as appropriate. RESULTS:Eighty-one RP and 130 TA procedures were performed, 26 (12.3%) and 60 (28.4%), respectively in obese patients (BMI > 30). Among the obese patients, operative time and estimated blood loss were less for RP (90 versus 130 min; P < 0.001 and 0 versus 50 mL; P < 0.001). Differences in the length of stay, overall mortality, incidence and severity of postoperative complications, and rates of readmission were not statistically significant between RP and TA procedures for all comers and in the obese patients. Controlling the operative characteristics and patient-specific factors, neither operative approach nor obesity was found to independently predict the postoperative complications. CONCLUSIONS:Laparoscopic RP adrenalectomy is a safe and feasible technique for obese patients. In the obese patients and for all comers, it offers shorter operative time, decreased estimated blood loss, with comparable length of stay and morbidity and mortality rates. We therefore recommend that this technique should be considered for patients undergoing adrenal resection.

OBJECTIVES/OBJECTIVE:The purpose of this study was to evaluate the utility of intraoperative sonography of the liver in the staging of pancreatic adenocarcinoma and its impact on the rate of postoperative tumor recurrence in the liver. METHODS:We performed a retrospective analysis of the rate in which intraoperative sonography of the liver changed surgical management in 470 surgical candidates with pancreatic adenocarcinoma. In postsurgical patients, we performed a χ(2) analysis to examine whether the patients who underwent hepatic intraoperative sonography had a lower rate of recurrent disease in the liver within the first 6 months of surgery compared to patients who did not undergo the procedure. RESULTS:Hepatic intraoperative sonography affected management in less than 1% of cases, detecting 1 unsuspected liver metastasis in 470 surgical patients with pancreatic adenocarcinoma. Of 3 patients with equivocal liver lesions identified on preoperative computed tomography or magnetic resonance imaging, hepatic intraoperative sonography excluded metastasis and cleared all the patients for surgical resection. There was no significant difference in postoperative liver recurrence between the group of patients who received intraoperative sonography before resection and patients who did not have the procedure done (P > .99). CONCLUSIONS:Routine intraoperative sonography of the liver does not affect staging of pancreatic adenocarcinoma. It may be useful for evaluating equivocal lesions.

BACKGROUND:Accurate assessment of complications is critical in analysing surgical outcomes. The post-operative morbidity index (PMI), derived from the Modified Accordion Severity Grading System and American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP), is a quantitative measure of post-operative morbidity. This study utilizes PMI to establish the complication burden for a distal pancreatectomy (DP). METHODS:From 2005-2011, nine centres contributed ACS-NSQIP complication data for 655 DPs. Each complication was assigned an Accordion severity weight ranging from 0.11 for grade 1 to 1.00 for grade 6 (death). The PMI is the sum of complication severity weights divided by the total number of patients. RESULTS:ACS-NSQIP complications occurred in 177 patients (27.0%). The non risk-adjusted PMI for DP is 0.087. Bleeding/Transfusion and Organ Space Infection were the most common complications. Frequency and burden differed across Accordion grades. While grade 4-6 complications represented only 15.4% of complication occurrences, they accounted for 30.4% of the burden. Subgroup analysis demonstrates that the PMI did not vary based on laparoscopic versus open approach or the performance of a splenectomy. DISCUSSION/CONCLUSIONS:This study uses two validated systems to quantitatively establish the morbidity of a DP. The PMI allows estimation of both the frequency and severity of complications and thus provides a more comprehensive assessment of risk.

BACKGROUND:Large centralized databases are used with increasing frequency for reporting hospital-specific and nationwide trends and outcomes after various surgical procedures in order to improve quality of surgical care. American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) is a risk-adjusted, case-weighted complication tracking initiative that reports 30-day outcomes from more than 400 academic and community institutions in the US. However, the accuracy of event reporting specific to pancreatic surgery has never been examined in depth. METHODS:We retrospectively reviewed medical records of patients, the information on whose postoperative course was originally reported through ACS-NSQIP between 2006 and 2010. Preoperative characteristics, operative data, and postoperative events were recorded after review of electronic medical records including physician and nursing notes, operative room records and anesthesiologist reports. Fidelity of reported clinical events was assessed. Accuracy, sensitivity, and specificity were calculated for each variable of interest. RESULTS:Two hundred and forty-nine pancreatectomies were reviewed, including 145 (58.2 %) Whipple procedures, 19 (7.6 %) total pancreatectomies, 65 (26.1 %) distal pancreatectomies, and 15 (6.0 %) central or partial resections. Median age was 65.7, males comprised 41.5 % of the group, and 74.3 % of patients were Caucasian. The overall rate of complications reported by NSQIP was 44.0 %, compared with 45.0 % in our review, however discordance was observed in 27.3 % of the time, including 34 cases of reporting a complication where there was not one, and 34 cases of missed complication. The most frequently reported event was postoperative bleeding requiring transfusion, however this was also the event most commonly misclassified. Additionally, three procedures unrelated to the index operation were recorded as reoperation events. While a pancreas-specific module does not yet exist, ACS-NSQIP reports a 7.6 % rate of organ-space surgical site infections; when compared with our institutional rate of Grades B and C postoperative fistula (10.4 %), we observed discordance 4.4 % of the time. Delayed gastric emptying, a common post-pancreatectomy morbidity, was not captured at all. Additionally, there were significant inaccuracies in reporting urinary tract infections, postoperative pneumonia, wound complications, and postoperative sepsis, with discordance rates of 4.4, 3.2, 3.6, and 6.8 %, respectively. CONCLUSIONS:ACS-NSQIP data are an important and valuable tool for evaluating quality of surgical care, however pancreatectomy-specific postoperative events are often misclassified, underscoring the need for a hepatopancreatobiliary-specific module to better capture key outcomes in this complex and unique patient population.

BACKGROUND:The diagnosis of serous cystadenoma (SCA), a rare benign pancreatic neoplasm, can alter the management of patients with pancreatic masses. Although characteristic imaging findings and fluid chemical analysis have been described, SCAs are not always recognized preoperatively. Furthermore, scant cellular yield on fine-needle aspiration (FNA) often leads to a nondiagnostic or nonspecific benign diagnosis. α-Inhibin (AI), a sensitive marker for SCA, is infrequently required for diagnosis in surgical specimens due to their characteristic histologic appearance. The objective of the current study was to determine whether AI staining can improve SCA diagnosis on FNA specimens. METHODS:Fifteen confirmed cases of SCA with prior FNA specimens were selected for this study. FNAs were evaluated for cellularity, cellular arrangement, and cytomorphology. Resection specimens were reviewed. RESULTS:Of the 15 FNA cases, approximately 75% demonstrated scant cellularity (11 of 15 cases). On smears, the cells were arranged as flat sheets, corresponding to strips of cells on cell block sections. The cells were small and round to cuboidal, with clear cytoplasm; occasional plasmacytoid cells and oncocytic cells were identified. Flattened cells, corresponding to attenuated epithelial cells lining macrocysts on the resections, were also noted. Stromal fragments were present in 5 FNAs and correlated with the hyalinized stroma in the resection specimens. AI immunostaining was positive in 88% of cases (7 of 8 of cases), thereby supporting the diagnosis of SCA. CONCLUSIONS:The results of the current study indicate that low cellularity and bland cytology are inherent to SCAs. Performing cell blocks and AI staining on FNA specimens is useful for establishing the diagnosis of SCA. An immunohistochemical panel including AI, chromogranin, and synaptophysin may enhance the diagnostic accuracy of pancreatic FNA specimens.

BACKGROUND:Quality of life after total pancreatectomy (TP) is perceived to be poor secondary to insulin-dependent diabetes and pancreatic insufficiency. As a result, surgeons may be reluctant to offer TP for benign and premalignant pancreatic diseases. METHODS:We retrospectively reviewed presenting features, operative characteristics, and postoperative outcomes of all patients who underwent TP at our institution. Quality of life was assessed using institutional questionnaires and validated general, pancreatic disease-related, and diabetes-related instruments (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire [EORTC QLQ-C30 and module EORTC-PAN26], Audit of Diabetes Dependent Quality of Life), and compared with frequency-matched controls, patients after a pancreaticoduodenectomy (PD). Continuous variables were compared using Student t-test or analysis of variance. Categorical variables were compared using χ(2) or Fisher exact test. RESULTS:Between 1994 and 2011, 77 TPs were performed. Overall morbidity was 49%, but only 15.8% patients experienced a major complication. Perioperative mortality was 2.6%. Comparing 17 TP and 14 PD patients who returned surveys, there were no statistically significant differences in quality of life in global health, functional status, or symptom domains of EORTC QLQ-C30 or in pancreatic disease-specific EORTC-PAN26. TP patients had slightly but not significantly higher incidence of hypoglycemic events as compared with PD patients with postoperative diabetes. A negative impact of diabetes assessed by Audit of Diabetes Dependent Quality of Life did not differ between TP and PD. Life domains most negatively impacted by diabetes involved travel and physical activity, whereas self-confidence, friendships and personal relationships, motivation, and feelings about the future remained unaffected. CONCLUSIONS:Although TP-induced diabetes negatively impacts select activities and functions, overall quality of life is comparable with that of patients who undergo a partial pancreatic resection.

BACKGROUND:Pancreatic surgery with vascular reconstruction is increasingly performed to offer the benefits of surgical resection to patients with locally advanced disease. The short- and long-term patency rates and the clinical significance of thrombosis of such reconstructions are unknown. METHODS:We reviewed pancreatectomies requiring venous reconstruction from 1994 to 2011. We sought to identify predictors of acute (within 30 days) and late thrombosis. We compared survival of patients with thrombosis to patients with patent reconstructions. RESULTS:Of 203 pancreatectomies requiring venous reconstruction, acute thrombosis occurred in nine (4.4 %) cases and was associated with increased perioperative mortality (22.2 versus 4.6 %, p = 0.023). Even when nonfatal, acute thrombosis was associated with decreased median survival (7.1 versus 15.9 months, p = 0.011) and increased hazard of death (hazard ratio 8.6, confidence interval 3.7-19.9, p < 0.001). A late loss of patency was seen in 31.2 % of cases at a median of 9.5 months. Later loss of patency was not associated with decreased median survival or increased hazard of death. CONCLUSIONS:Acute thrombosis of the portal venous reconstructions after pancreatectomy is associated with increased perioperative mortality and, even when nonfatal, is associated with decreased survival. Late loss of patency occurs in one-third of patients but does not affect survival.