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Su1653 Trends in Pancreatic Surgery: Indications, Operative Techniques and Postoperative Outcome of 1120 Pancreatic Resections
Su1650
technique led to preservation a long GDA stump and use of a large metallic clip as a radiographic marker/guide. This was found to aid in easier and quicker IR localization and coiling or stenting of the bleeding vessel. The mortality rate has decreased to 0% in patients undergoing immediate IR intervention.
Preoperative Prediction of the "High-Risk Pancreas" by Artificial Neuronal Network Analysis of Over 450 Pancreatoduodenectomies Hryhoriy Lapshyn, Frank Makowiec, Dirk Bausch, Ulrich T. Hopt, Tobias Keck, Ulrich Wellner
Su1653
Introduction: Pancreatoduodenectomy (PD) has become a standard operation with low mortality in high-volume centers, however perioperative morbidity remains substantial, mainly due to postoperative pancreatic fistula (POPF). Development of preoperative protective measures is hampered by a lack of strictly preoperative risk stratification. Predictive power of single parameters can be enhanced by optimally weighed combination of risk factors in an artificial neuronal network (ANN). Methods: A panel of clinical and radiological parameters were assessed retrospectively from patients with pancreatoduodenectomy in our institution and risk factors analysis for the endpoint POPF (clinically relevant Grade B/C of ISGPS definition) were identified. Preoperatively available parameters were used for prediction of a high risk pancreas in an ANN. Internal validation of the thereby identified risk group was performed by testing for POPF and other relevant complications. Results A total of 471 patients with PD operated from 2001 to 2012 were included. Out of twelve clinical and radiological risk factors for POPF B/C, the most powerful was a soft pancreas. When an ANN was trained to predict a soft high-risk pancreas, correct prediction was achieved in 83% in the test group. Patients predicted to have a high-risk pancreas had a significantly higher rate of POPF and severe complications compared to the low-risk group (POPF B/C (38% vs 8%, p=0.000), intraabdominal abscess (23% vs 10%, p=0.000), severe complications (26% vs 13%, p=0.003), severe postpancreatectomy hemorrhage (18% vs 6%, p=0.012)), as well as a five-fold elevated mortality (5% vs 1%, p=0.034). Conclusion Clinical and radiological parameters combined in an ANN model can correctly predict a high-risk pancreas and severe complications already before the operation.
Trends in Pancreatic Surgery: Indications, Operative Techniques and Postoperative Outcome of 1120 Pancreatic Resections Frank Makowiec, Tobias Keck, Ulrich Adam, Hartwig Riediger, Uwe A. Wittel, Ulrich F. Wellner, Ulrich T. Hopt Low mortality rates after pancreatic resection (PaRes) have been reported by many centers. Hospital volume, surgeon volume and adequate management of complications are factors contributing to a better outcome. The aim of our study was to evaluate trends in indications, operative techniques and postoperative outcome in more than 1100 PaRes performed in our institution since 1994. Methods: 1120 PaRes were performed since 1994. The vast majority of the operations was performed by three surgeons. The perioperative data were documented in a pancreatic database. For our analyses the study period was subclassified into three periods (A 1994-2001/n=363; B 2001-2006/n=305; C since 2007/n=452). Results: 81% of the PaRes were personally performed by one of the 3 principal surgeons. The average annual number of PaRes increased from 52 (period A) to 80 (C; n=107 in 2011). The median age increased from 51 (A) to 65 years (C; p ,0.001). In the entire group (n=1120) indications for surgery were pancreatic/periampullary cancer (49%), chronic pancreatitis (CP; 33%) and various other lesions (18%). The percentage of PaRes for CP decreased from over 50% in period A to 17% (C; p ,0.01). In contrast the frequency of IPMNs increased from below 1% (A) to 8% (C; p ,0.05). About two thirds of the operations were pancreaticoduodenectomies (most PPPD). Due to the lower numbers of operations for CP the rates of duodenum-preserving resections decreased from 18% (A) to 4% (C; p ,0.05). A more aggressive approach in some patients with cancer and more resected IPMNs led to an increase in total pancreatectomies during the study period from 1% (A) to 6% (C). The frequency of mesenterico-portal vein resections increased from 8% (A) to 20% (C; p ,0.01). Distal resections were performed in 17%. Laparoscopic pancreatic head and distal resections were introduced by one surgeon in period C and were performed in 4.7% of all cases (12% of the cases in period C). Overall mortality was 2.4% and comparable in the 3 periods (2.8%, 2.0%, 2.4%; p=0.8). The 3 principal surgeons in our series also had comparable mortality rates (1.9-3.4%; p=0.41). Overall complication rates increased from 42% (A) to 56% (C; p,0.01). The rate of pancreatic leak grade B/C also increased from 5% (A) to 12% (C; p,0.01) but the frequencies of relaparotomies were comparable (10-14%; n.s.) Conclusions: Operative mortality in our high-volume institutional series of more than 1100 pancreatic resections was low throughout the study period. Mortality remained low despite a more aggressive surgical approach to (malignant) pancreatic disease (more extended resections, more vein resections, older patients). An increased overall morbidity may be explained by more clinically relevant pancreatic fistulas (more patients with soft pancreas) and better documentation (many patients in randomized studies after period A).
Su1651
SSAT Abstracts
Activation of Pancreatic Enzyme Plus Bacterial Infection Plays an Important Role in the Pathogenic Mechanism of Clinically Relevant POPF After Pancreaticoduodenectomy Kenichiro Uemura, Yoshiaki Murakami, Takeshi Sudo, Yasushi Hashimoto, Naru Kondo, Naoya Nakagawa, Hayato Sasaki, Kenjiro Okada, Hiroki Ohge, Taijiro Sueda Background: Postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD) is relatively common, and remains a major cause of morbidity and surgical mortality. However, the underlying pathogenic mechanism of POPF, with the exception of technical error, still remains unclear. We previously reported that postoperative pancreatitis after PD plays an important role in the pathogenic mechanism of POPF after PD. We hypothesized that the bacterial infection in addition to the activation of pancreatic enzyme around the pancreatico-enteric anastomosis could be associated with occurrence of clinically relevant POPF (CR-POPF) after PD. Objectives: We retrospectively analyzed the possible association of postoperative pancreatitis, bacterial colonization in the surgical drain, and CR-POPF after PD using prospectively collected data base. Methods: 250 consecutive patients undergoing PD were included. All patients were administered prophylactic antibiotics, which were selected based on perioperative bile cultures. POPFs were diagnosed by International Study Group Pancreatic Fistula (ISGPF) criteria. Hyperamylasemia was defined as serum amylase more than 3 times the upper limit of the reference value. Closed suction drains were inserted along the pancreatico-enteric anastomosis, and surgical drains were examined bacteriologically when they were removed. Results: Of 250 patients, 23% developed POPF; Grade A in 16%, Grade B in 6%, and Grade C in 1%. A total of 32% of the patients had hyperamylasemia on postoperative day (POD) 1, and the presence of hyperamylasemia on POD1 was closely associated with the development of POPF (p ,0.01). A total of 43% of the patients had bacterial colonization in the surgical drain. In the patients without bacteria in surgical drain, only 1% of the patients developed CR-POPFs, while 29% of the patients with bacteria in surgical drain developed CR-POPFs (p,0.01). Moreover, in the patients without hyperamylasemia and no bacterial colonization in the surgical drain, no patients developed CRPOPF, while 60% of the patients with CR-POPF had both hyperamylasemia and bacterial colonization in the surgical drain (p ,0.01). Conclusion: Bacterial infection in addition to activation of pancreatic enzyme around the pancreatico-enteric anastomosis might play an important role in the pathogenic mechanism of CR-POPF after PD. Prevention of postoperative pancreatitis of remnant pancreas with infection control might be an area of focus for reducing the incidence of CR-POPF after PD.
Su1655 Is Frozen Section Histopathology of Any Value in Patients Undergoing Resection of Intraductal Papillary Mucinous Neoplasms? Daniel Joyce, Gavin A. Falk, Kevin M. El-Hayek, Sricharan Chalikonda, Gareth MorrisStiff, Matthew Walsh INTRODUCTION: Intraductal papillary mucinous neoplasms (IPMN) are cystic lesions of the pancreas that follow a step-wise dysplastic sequence from adenoma to invasive adenocarcinoma. Obtaining a frozen section (FS) at the time of pancreatic resection could be important to determine whether additional resection of the remnant is required. The aim of this study is to report the correlation between FS of the pancreatic neck and final histopathology for patients with IPMN including those with IPMN carcinomas. METHODS: The departmental pancreatic cyst database was interrogated to identify all patients with a histopathological diagnosis of IPMN with or without pancreatic adenocarcinoma arising from within the IPMN. The degree of dysplasia on the final pathology report was classified as high (HGD), moderate (MGD), or low (LGD. Frozen section results were reviewed with particular reference to identification of invasive carcinoma or high-grade dysplasia and these findings were compared to final histopathological findings, and related to patient outcome. RESULTS: During the period January 2000 to December 2011, 121 patients underwent resection, consisting of 41 patients with an invasive carcinoma and 80 with IPMN alone: HGD [n=18]; MGD [n= 14]; and LGD [n=48] (on final pathology). There were 70 females and 51 males with a median age of 68 years (IQR: 58-73). Of the patients with IPMN carcinomas, 36 (88%) had a FS. Carcinoma or HGD was seen at the transaction margin on FS in 4 patients undergoing pancreatoduodenectomy leading to 4 extended resections, 2 of which were total pancreatectomies. There was 1 false-positive for invasive cancer that was found to be non invasive on final pathology and 1 false-negative for HGD/invasive carcinoma on frozen section that was found to be an invasive cancer on final pathology. For those with IPMN alone, 64 had frozen section analysis performed. None had carcinoma/HGD at the transection margin on FS or on subsequent histopathology. 3 patients in this group died of IPMN-related carcinomas in their remnant pancreas. 2 had HGD on their initial resection and 1 had only LGD, and all developed the subsequent cancers away from the transaction margin. CONCLUSIONS: Frozen section analysis allows identification of foci of carcinoma or HGD at the transection margin during pancreatic resection for IPMN that should result in further resection. However, the development of progressive disease in the pancreatic remnants of patients without initial evidence of carcinoma means that radiological surveillance is required for this cohort.
Su1652 Evolution of the Treatment of Gastroduodenal Artery Pseudoaneurysms and Mesenteric Arterial Hemorrhage Following Pancreaticoduodenectomy Joseph Chen, Laura Findeiss, Aram N. Demirjian, David K. Imagawa Introduction: Postoperative mortality in high volume centers for pancreaticoduodenectomy (Whipple) has decreased to less than 4%. Late postoperative bleeding occurs in 0.5-5% of cases, with reported mortality rates of up to 60%. Patients/Methods: This is a retrospective analysis of 313 patients who underwent pancreaticoduodenectomy from 2003-2012 at our institution, a high-volume, multidisciplinary hepato-pancreato-biliary center. The main outcome measure was mortality. Results: From 2003-2012, 10 out of 313 patients (3%) presented with delayed major hemorrhage following pancreaticoduodenectomy, occurring between postoperative days 6-18. Visceral arteries known to be affected were the gastroduodenal artery (GDA) (4), hepatic artery (3), and the pancreaticoduodenal artery (1). 5 patients presented with gastrointestinal hemorrhage and 5 patients presented with hemoperitoneum. 1 patient underwent immediate operative intervention, 2 patients underwent immediate operation followed by percutaneous intervention by interventional radiology (IR). Immediate IR intervention was performed in 7 patients. Mortality from GDA/visceral arterial hemorrhage occurred in 1 patient (10%). Conclusion: Delayed mesenteric arterial hemorrhage following pancreaticoduodenectomy requires early recognition and management. The mortality rate in our early experience with immediate operative intervention was 33%. A modified operative
SSAT Abstracts
S-1082
technique led to preservation a long GDA stump and use of a large metallic clip as a radiographic marker/guide. This was found to aid in easier and quicker IR localization and coiling or stenting of the bleeding vessel. The mortality rate has decreased to 0% in patients undergoing immediate IR intervention.
Preoperative Prediction of the "High-Risk Pancreas" by Artificial Neuronal Network Analysis of Over 450 Pancreatoduodenectomies Hryhoriy Lapshyn, Frank Makowiec, Dirk Bausch, Ulrich T. Hopt, Tobias Keck, Ulrich Wellner
Su1653
Introduction: Pancreatoduodenectomy (PD) has become a standard operation with low mortality in high-volume centers, however perioperative morbidity remains substantial, mainly due to postoperative pancreatic fistula (POPF). Development of preoperative protective measures is hampered by a lack of strictly preoperative risk stratification. Predictive power of single parameters can be enhanced by optimally weighed combination of risk factors in an artificial neuronal network (ANN). Methods: A panel of clinical and radiological parameters were assessed retrospectively from patients with pancreatoduodenectomy in our institution and risk factors analysis for the endpoint POPF (clinically relevant Grade B/C of ISGPS definition) were identified. Preoperatively available parameters were used for prediction of a high risk pancreas in an ANN. Internal validation of the thereby identified risk group was performed by testing for POPF and other relevant complications. Results A total of 471 patients with PD operated from 2001 to 2012 were included. Out of twelve clinical and radiological risk factors for POPF B/C, the most powerful was a soft pancreas. When an ANN was trained to predict a soft high-risk pancreas, correct prediction was achieved in 83% in the test group. Patients predicted to have a high-risk pancreas had a significantly higher rate of POPF and severe complications compared to the low-risk group (POPF B/C (38% vs 8%, p=0.000), intraabdominal abscess (23% vs 10%, p=0.000), severe complications (26% vs 13%, p=0.003), severe postpancreatectomy hemorrhage (18% vs 6%, p=0.012)), as well as a five-fold elevated mortality (5% vs 1%, p=0.034). Conclusion Clinical and radiological parameters combined in an ANN model can correctly predict a high-risk pancreas and severe complications already before the operation.
Trends in Pancreatic Surgery: Indications, Operative Techniques and Postoperative Outcome of 1120 Pancreatic Resections Frank Makowiec, Tobias Keck, Ulrich Adam, Hartwig Riediger, Uwe A. Wittel, Ulrich F. Wellner, Ulrich T. Hopt Low mortality rates after pancreatic resection (PaRes) have been reported by many centers. Hospital volume, surgeon volume and adequate management of complications are factors contributing to a better outcome. The aim of our study was to evaluate trends in indications, operative techniques and postoperative outcome in more than 1100 PaRes performed in our institution since 1994. Methods: 1120 PaRes were performed since 1994. The vast majority of the operations was performed by three surgeons. The perioperative data were documented in a pancreatic database. For our analyses the study period was subclassified into three periods (A 1994-2001/n=363; B 2001-2006/n=305; C since 2007/n=452). Results: 81% of the PaRes were personally performed by one of the 3 principal surgeons. The average annual number of PaRes increased from 52 (period A) to 80 (C; n=107 in 2011). The median age increased from 51 (A) to 65 years (C; p ,0.001). In the entire group (n=1120) indications for surgery were pancreatic/periampullary cancer (49%), chronic pancreatitis (CP; 33%) and various other lesions (18%). The percentage of PaRes for CP decreased from over 50% in period A to 17% (C; p ,0.01). In contrast the frequency of IPMNs increased from below 1% (A) to 8% (C; p ,0.05). About two thirds of the operations were pancreaticoduodenectomies (most PPPD). Due to the lower numbers of operations for CP the rates of duodenum-preserving resections decreased from 18% (A) to 4% (C; p ,0.05). A more aggressive approach in some patients with cancer and more resected IPMNs led to an increase in total pancreatectomies during the study period from 1% (A) to 6% (C). The frequency of mesenterico-portal vein resections increased from 8% (A) to 20% (C; p ,0.01). Distal resections were performed in 17%. Laparoscopic pancreatic head and distal resections were introduced by one surgeon in period C and were performed in 4.7% of all cases (12% of the cases in period C). Overall mortality was 2.4% and comparable in the 3 periods (2.8%, 2.0%, 2.4%; p=0.8). The 3 principal surgeons in our series also had comparable mortality rates (1.9-3.4%; p=0.41). Overall complication rates increased from 42% (A) to 56% (C; p,0.01). The rate of pancreatic leak grade B/C also increased from 5% (A) to 12% (C; p,0.01) but the frequencies of relaparotomies were comparable (10-14%; n.s.) Conclusions: Operative mortality in our high-volume institutional series of more than 1100 pancreatic resections was low throughout the study period. Mortality remained low despite a more aggressive surgical approach to (malignant) pancreatic disease (more extended resections, more vein resections, older patients). An increased overall morbidity may be explained by more clinically relevant pancreatic fistulas (more patients with soft pancreas) and better documentation (many patients in randomized studies after period A).
Su1651
SSAT Abstracts
Activation of Pancreatic Enzyme Plus Bacterial Infection Plays an Important Role in the Pathogenic Mechanism of Clinically Relevant POPF After Pancreaticoduodenectomy Kenichiro Uemura, Yoshiaki Murakami, Takeshi Sudo, Yasushi Hashimoto, Naru Kondo, Naoya Nakagawa, Hayato Sasaki, Kenjiro Okada, Hiroki Ohge, Taijiro Sueda Background: Postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD) is relatively common, and remains a major cause of morbidity and surgical mortality. However, the underlying pathogenic mechanism of POPF, with the exception of technical error, still remains unclear. We previously reported that postoperative pancreatitis after PD plays an important role in the pathogenic mechanism of POPF after PD. We hypothesized that the bacterial infection in addition to the activation of pancreatic enzyme around the pancreatico-enteric anastomosis could be associated with occurrence of clinically relevant POPF (CR-POPF) after PD. Objectives: We retrospectively analyzed the possible association of postoperative pancreatitis, bacterial colonization in the surgical drain, and CR-POPF after PD using prospectively collected data base. Methods: 250 consecutive patients undergoing PD were included. All patients were administered prophylactic antibiotics, which were selected based on perioperative bile cultures. POPFs were diagnosed by International Study Group Pancreatic Fistula (ISGPF) criteria. Hyperamylasemia was defined as serum amylase more than 3 times the upper limit of the reference value. Closed suction drains were inserted along the pancreatico-enteric anastomosis, and surgical drains were examined bacteriologically when they were removed. Results: Of 250 patients, 23% developed POPF; Grade A in 16%, Grade B in 6%, and Grade C in 1%. A total of 32% of the patients had hyperamylasemia on postoperative day (POD) 1, and the presence of hyperamylasemia on POD1 was closely associated with the development of POPF (p ,0.01). A total of 43% of the patients had bacterial colonization in the surgical drain. In the patients without bacteria in surgical drain, only 1% of the patients developed CR-POPFs, while 29% of the patients with bacteria in surgical drain developed CR-POPFs (p,0.01). Moreover, in the patients without hyperamylasemia and no bacterial colonization in the surgical drain, no patients developed CRPOPF, while 60% of the patients with CR-POPF had both hyperamylasemia and bacterial colonization in the surgical drain (p ,0.01). Conclusion: Bacterial infection in addition to activation of pancreatic enzyme around the pancreatico-enteric anastomosis might play an important role in the pathogenic mechanism of CR-POPF after PD. Prevention of postoperative pancreatitis of remnant pancreas with infection control might be an area of focus for reducing the incidence of CR-POPF after PD.
Su1655 Is Frozen Section Histopathology of Any Value in Patients Undergoing Resection of Intraductal Papillary Mucinous Neoplasms? Daniel Joyce, Gavin A. Falk, Kevin M. El-Hayek, Sricharan Chalikonda, Gareth MorrisStiff, Matthew Walsh INTRODUCTION: Intraductal papillary mucinous neoplasms (IPMN) are cystic lesions of the pancreas that follow a step-wise dysplastic sequence from adenoma to invasive adenocarcinoma. Obtaining a frozen section (FS) at the time of pancreatic resection could be important to determine whether additional resection of the remnant is required. The aim of this study is to report the correlation between FS of the pancreatic neck and final histopathology for patients with IPMN including those with IPMN carcinomas. METHODS: The departmental pancreatic cyst database was interrogated to identify all patients with a histopathological diagnosis of IPMN with or without pancreatic adenocarcinoma arising from within the IPMN. The degree of dysplasia on the final pathology report was classified as high (HGD), moderate (MGD), or low (LGD. Frozen section results were reviewed with particular reference to identification of invasive carcinoma or high-grade dysplasia and these findings were compared to final histopathological findings, and related to patient outcome. RESULTS: During the period January 2000 to December 2011, 121 patients underwent resection, consisting of 41 patients with an invasive carcinoma and 80 with IPMN alone: HGD [n=18]; MGD [n= 14]; and LGD [n=48] (on final pathology). There were 70 females and 51 males with a median age of 68 years (IQR: 58-73). Of the patients with IPMN carcinomas, 36 (88%) had a FS. Carcinoma or HGD was seen at the transaction margin on FS in 4 patients undergoing pancreatoduodenectomy leading to 4 extended resections, 2 of which were total pancreatectomies. There was 1 false-positive for invasive cancer that was found to be non invasive on final pathology and 1 false-negative for HGD/invasive carcinoma on frozen section that was found to be an invasive cancer on final pathology. For those with IPMN alone, 64 had frozen section analysis performed. None had carcinoma/HGD at the transection margin on FS or on subsequent histopathology. 3 patients in this group died of IPMN-related carcinomas in their remnant pancreas. 2 had HGD on their initial resection and 1 had only LGD, and all developed the subsequent cancers away from the transaction margin. CONCLUSIONS: Frozen section analysis allows identification of foci of carcinoma or HGD at the transection margin during pancreatic resection for IPMN that should result in further resection. However, the development of progressive disease in the pancreatic remnants of patients without initial evidence of carcinoma means that radiological surveillance is required for this cohort.
Su1652 Evolution of the Treatment of Gastroduodenal Artery Pseudoaneurysms and Mesenteric Arterial Hemorrhage Following Pancreaticoduodenectomy Joseph Chen, Laura Findeiss, Aram N. Demirjian, David K. Imagawa Introduction: Postoperative mortality in high volume centers for pancreaticoduodenectomy (Whipple) has decreased to less than 4%. Late postoperative bleeding occurs in 0.5-5% of cases, with reported mortality rates of up to 60%. Patients/Methods: This is a retrospective analysis of 313 patients who underwent pancreaticoduodenectomy from 2003-2012 at our institution, a high-volume, multidisciplinary hepato-pancreato-biliary center. The main outcome measure was mortality. Results: From 2003-2012, 10 out of 313 patients (3%) presented with delayed major hemorrhage following pancreaticoduodenectomy, occurring between postoperative days 6-18. Visceral arteries known to be affected were the gastroduodenal artery (GDA) (4), hepatic artery (3), and the pancreaticoduodenal artery (1). 5 patients presented with gastrointestinal hemorrhage and 5 patients presented with hemoperitoneum. 1 patient underwent immediate operative intervention, 2 patients underwent immediate operation followed by percutaneous intervention by interventional radiology (IR). Immediate IR intervention was performed in 7 patients. Mortality from GDA/visceral arterial hemorrhage occurred in 1 patient (10%). Conclusion: Delayed mesenteric arterial hemorrhage following pancreaticoduodenectomy requires early recognition and management. The mortality rate in our early experience with immediate operative intervention was 33%. A modified operative
SSAT Abstracts
S-1082