Back to Authors

Kendrick, Michael

Mayo Clinic

Mayo Clinic

Citations 10

International Reference Values for Surgical Outcomes of Total Pancreatectomy
Berchtold, Caroline , Kuemmerli, Christoph, Li, Zhihao , Eden, Janina , Wu, Pengfei , Cecchetto, Sara Nicole, Kendrick, Michael L. , Pecorelli, Nicolò , Guarneri, Giovanni , Farooqui, Waqas , Tschuor, Christoph , Burgdorf, Stefan Kobbelgaard , Mühlhäusser, Julia , Gass, Jörn‐Markus , Koh, Ye-Xin, Seip, Tomas, Santibañes, Martín de , Todeschini, Letizia , Marchegiani, Giovanni, Belfil, Nadiya , Boggi, Ugo, Cappelle, Marie , Koerkamp, Bas Groot , Dutkowski, Philipp , Hackert, Thilo , Truty, Mark J. , Group, Outcomes for Total Pancreatectomy, Valle, Valentina , Giulianotti, Pier Cristoforo , Pessaux, Patrick, Thapa, Prabin , Kuzman, Matta , Pandanaboyana, Sanjay, He, Jin , Kendrick, Michael, Truty, Mark, Li, Zhihao , Groot Koerkamp, Bas , Müller, Philip C , Breuer, Eva , Vallorani, Alessia , Hansen, Carsten Palnæs , Guidetti, Cristiano , Campbell, Brady A. , Cecchetto, Sara Nicole, Gudmundsdottir, Hallbera , Starlinger, Patrick , Goh, Brian K P , Koh, Ye-Xin , Rebelo, Artur , Kleeff, Jorg H. , Marchegiani, Giovanni , Lesurtel, Mickaël , Machado, Marcel Autran C. , Kauffmann, Emanuele F. , Benedetto, Fabrizio Di , Roberts, Keith John , Nevler, Avinoam , Lavu, Harish , Nickel, Felix , He, Jing , Falconi, Massimo , Billeter, Adrian T. , Müller-Stich, Beat Peter , Group, Outcomes for Total Pancreatectomy, Halle-Smith, James Michael , Giannone, Fabio , Pessaux, Patrick , Sánchez‐Velázquez, Patricia , Maharjan, Dhiresh Kumar , Torres, Orlando Jorge Martins

JAMA Surgery | November 12, 2025 | Volume: 161 | Issue: 1 | Pages: 50

10.1001/jamasurg.2025.4941 Get It

Importance Total pancreatectomy (TP) is indicated for advanced pancreatic cancer or multifocal tumors. Furthermore, TP may be performed to avoid the risk of pancreatic fistula in selected patients to improve the perioperative risk profile. Objective To define reference values for TP based on a low-risk cohort treated at expert centers. Design, Setting, and Participants This multicenter study analyzed outcomes from patients undergoing primary TP for malignant or benign lesions from 25 international expert centers from January 2017 to November 2023. Low-risk patients undergoing TP (LR-TP) were without vascular resections or significant comorbidities. Exposures TP. Main Outcomes and Measures Twenty reference values were derived from the 75th or the 25th percentile of the median values of all centers. Outcomes of LR-TP were compared with a cohort of TP with vascular resection, TP due to high-risk pancreatic anastomosis, and the benchmark values for low-risk pancreatoduodenectomy. Results Of 994 patients, 333 (33.5%; median [IQR] age, 66 [58-72] years; 171 male [51.4%]) qualified as the LR-TP cohort. Reference values included blood loss (≤1000 mL), major complications (≤37%), 3-month postoperative mortality (<6%), and retrieved lymph nodes (≥29). Compared with TP with vascular resections, reference cutoffs were not met for major complications (51% vs LR-TP ≤37%) and 90-day mortality (11% vs LR-TP ≤6%). For TP due to high-risk anastomosis, failure to rescue rate (38% vs ≤6%) and 90-day mortality (11% vs LR-TP ≤6%) were not met. Compared with pancreatoduodenectomy, reference values for postoperative mortality were 3 times higher for LR-TP (≤2% vs ≤6%) and less for resected lymph nodes (≥16 vs ≥29). Conclusions and Relevance This case-control study provided global reference values for TP, indicating significantly higher postoperative morbidity and mortality compared with pancreatoduodenectomy. Perioperative morbidity of TP was especially increased in patients with vascular resections. These reference values can serve for quality control of pancreatic surgery.
Variations in the Use of Outpatient Surgery
Sangaralingham, Lindsey R. , Houten, Holly K. Van , Kendrick, Michael L. , Etzioni, David A. , Hanson, Kristine, Sangaralingham, Lindsey, Fong, Zhi, Kendrick, Michael, Etzioni, David, Zhang, Chi , Hanson, Kristine T. , Fong, Zhi Ven , Chang, Yu‐Hui , Habermann, Elizabeth B. , Thiels, Cornelius A.

JAMA Network Open | July 31, 2025 | Volume: 8 | Issue: 7 | Pages: e2524165

10.1001/jamanetworkopen.2025.24165 Get It

ImportanceIdentification of factors associated with variation in outpatient surgery may further quality improvement efforts to safely reduce postoperative hospital length of stay nationally.ObjectivesTo explore variation in the use of outpatient surgery, incorporating patient, geographic, and hospital factors.Design, Setting, and ParticipantsThis retrospective cross-sectional study used deidentified administrative claims data from OptumLabs Data Warehouse. Participants included adults who underwent 1 of 10 general, urological, or gynecological operations between January 1, 2015, and June 30, 2021, in the US. Patients who underwent combined procedures or reoperations or had at least 15 Elixhauser comorbidities were excluded. Data were analyzed from July 26 to December 16, 2023.ExposureInpatient or outpatient surgical procedures.Main Outcomes and MeasuresMultilevel logistic regression assessed variation in the use of outpatient surgery rates by hospital characteristics (bed size, presence of trainees, and rural referral center status) and hospital census division, adjusting for patient factors (age, sex, number of Elixhauser comorbidities, year, and rural-urban commuting area). This multilevel model allowed for the sources of variability to be quantitatively attributed to patient characteristics, geography, and hospital characteristics.ResultsA total of 330 424 (72.3%) of 456 954 included patients underwent outpatient surgery. The median age was 54 (IQR, 41-67) years, and of those with data available, most patients were female (268 692 of 414 193 [64.9%]). The likelihood of outpatient surgery varied significantly by hospital census division for all 10 operations (eg, MIS salpingo-oophorectomy range, 29.6%-58.8%; P < .001). Variation in hospital census division contributed most to outpatient surgery for 8 of 10 operations compared with other patient and hospital characteristics. Hospital census division contributed the greatest degree to the variation in outpatient simple mastectomy (20.6%) and the least to outpatient open ventral hernia repair (0.7%). Multivariable analysis showed that the odds of outpatient surgery for patients from metropolitan areas were higher for minimally invasive salpingo-oophorectomy (odds ratio [OR], 1.62; 95% CI, 1.34-1.95) and open ventral hernia repair (OR, 1.16; 95% CI, 1.09-1.24). Hospitals with 400 or more beds were independently associated with decreased odds of outpatient surgery compared with hospitals with 50 to 199 beds for 4 of 7 operations (MIS paraesophageal hernia repair [OR, 0.58; 95% CI, 0.47-0.71; P < .001]; MIS cholecystectomy [OR, 0.73; 95% CI, 0.68-0.78; P < .001]; open ventral hernia [OR, 0.51; 95% CI, 0.46-0.57; P < .001]; MIS ventral hernia repair [OR, 0.66; 95% CI, 0.56-0.77; P < .001]). The presence of a residency training program was independently associated with increased odds of outpatient surgery for simple mastectomy (OR, 1.35; 95% CI, 1.16-1.58; P < .001) and mastectomy with reconstruction (OR, 1.50; 95% CI, 1.27-1.77; P < .001) and decreased odds of outpatient surgery for minimally invasive cholecystectomy (OR, 0.96; 95% CI, 0.92-1.00; P = .04), open ventral hernia repair (OR, 0.93; 95% CI, 0.86-1.00; P = .04), and total thyroidectomy (OR, 0.84; 95% CI, 0.71-1.00; P = .04).Conclusions and RelevanceIn this cross-sectional study, significant variation existed in the use of outpatient surgery in the US and appeared to be driven primarily by hospital geography. Addressing these variations may improve the use of resources.
Imaging-based Surgical Site Infection Detection Using Artificial Intelligence
Muaddi, Hala , Anderson, Stephanie , Etzioni, David A. , McLaughlin, Sarah A. , Kendrick, Michael L. , Salehinejad, Hojjat , Anderson, Stephanie S., Etzioni, David, Kendrick, Michael, Choudhary, Ashok, Lee, Frank, Habermann, Elizabeth B. , Thiels, Cornelius A.

Annals of Surgery | July 3, 2025 | Volume: 282 | Issue: 3 | Pages: 419-428

10.1097/sla.0000000000006826 Get It

Objective: To develop an artificial intelligence–based pipeline to assess and triage patient-submitted postoperative wound images. Background: The rise of outpatient surgeries, remote monitoring, and patient-submitted wound images via online portals has contributed to a growing administrative workload on clinicians. Early identification of surgical site infection (SSI) is essential for reducing postoperative morbidity. Methods: Patients ≥18 years old who underwent surgery at 9 affiliated Mayo Clinic hospitals (2019-2022) and were captured by the National Surgical Quality Improvement Program (NSQIP) were included. Eligibility required submission of one image via the patient portal within 30 days after surgery. Images were independently screened in duplicate to determine the presence of an incision. SSI outcomes were obtained from NSQIP. The developed model consisted of 2 stages: incision detection and SSI detection in images with incisions. Four pretrained architectures were evaluated using 10-fold cross-validation, with upsampling and data augmentation to mitigate class imbalance. An end-to-end pipeline, image quality assessment and sensitivity analysis stratified by race were also performed. Results: Among 6060 patients, the median age was 54 years (interquartile range: 40–65), 61.4% (n=3805) were female, and 92.5% (n=5731) identified as White. SSIs were confirmed in 6.2% (n=386) images. Vision Transformer outperformed all others, achieving an incision detection accuracy of 0.94 (area under the curve=0.98) and an SSI detection accuracy of 0.73 (area under the curve=0.81). In addition, it demonstrated strong performance in assessing image quality. Sensitivity analysis revealed comparable performance across racial subgroups. Conclusion: This artificial intelligence pipeline demonstrates promising performance in automating wound image assessment and SSI detection, reducing clinical workload and improving postoperative care.
Comparative effectiveness of Roux‐en‐Y gastric bypass and sleeve gastrectomy in achieving diabetes remission in patients with diabetes‐related vascular diseases: A multicentred study
Ghusn, Wissam , Ma, Pearl , Ikemiya, Kayla , Salame, Marita , Kendrick, Michael, Higa, Kelvin , Hage, Karl , Mosleh, Kamal Abi , Storm, Andrew C. , Dayyeh, Barham K. Abu , Ghanem, Omar M.

Clinical Obesity | December 21, 2024 | Volume: 15 | Issue: 3 | Pages: No page available

10.1111/cob.12732 Get It

Summary Metabolic and bariatric surgeries (MBS), including Roux‐en‐Y Gastric Bypass (RYGB) and Sleeve Gastrectomy (SG), have proven effective in promoting long‐term diabetes remission among patients with type‐2 diabetes (T2D). In this multicentre retrospective cohort study, we investigated the effectiveness of RYGB and SG in achieving diabetes remission, specifically among patients with T2D and vascular complications, while accounting for similar baseline diabetes severity. Although various scores predict diabetes remission after bariatric surgery, they do not consider diabetes‐related vascular complications, which can influence outcomes even in patients with similar baseline T2D severity. We collected preoperative data on microvascular (retinopathy, nephropathy, neuropathy) and macrovascular comorbidities (coronary artery disease, cerebrovascular accidents, peripheral artery disease) to compare the efficacy of RYGB and SG. Among 961 patients analysed, those with vascular complications showed higher remission rates with RYGB (OR: 1.97) compared to SG, despite similar baseline diabetes severity. Notably, RYGB patients with microvascular complications had a significant advantage in achieving T2D remission (OR: 2.95). However, no significant differences in remission were observed in patients with macrovascular complications. These findings suggest that RYGB may be more effective than SG in specific patient populations, particularly those with microvascular complications, emphasizing the need for personalized treatment strategies.
Internal hernia in patients after duodenal switch: A multi‐centred comparative analysis
Lind, Romulo , Abich, Estela, Gonçalves, Graziella Galvão , Belluzzi, Amanda, Antunes, J. F. G. , Ghanem, Muhammad , Jawad, Muhammad A. , Kendrick, Michael, Teixeira, André , Hage, Karl , Abich, Estela, Antunes, Juliana, Ghanem, Omar M.

Clinical Obesity | December 18, 2024 | Volume: 15 | Issue: 3 | Pages: No page available

10.1111/cob.12729 Get It

Summary Biliopancreatic diversion with duodenal switch (BPD‐DS) and single anastomosis duodeno‐ileostomy with sleeve (SADI‐S) are associated with superior and sustained weight loss outcomes. Despite their growing popularity, long‐term safety profiles, particularly the risk of internal hernia (IH), remain underexplored. This study aimed to evaluate the incidence and characteristics of IH following BPD‐DS and SADI‐S procedures, comparing their clinical presentation, diagnostic methods, and outcomes. A retrospective chart review was performed for patients who underwent BPD‐DS or SADI‐S between 2008 and 2023 in two high‐volume tertiary referral centres for bariatric surgery in the United States. Demographic data, comorbidities, operative details, and follow‐up outcomes were collected. A subgroup analysis of IH cases was conducted to compare the incidence, location of hernias, and diagnostic modalities between procedures. Out of 1160 patients (85.1% BPD‐DS; 14.9% SADI‐S), the overall incidence of IH was 1.12%, with a higher rate in BPD‐DS (0.8%) than in SADI‐S (0.57%). Most IHs occurred within the first 24 months postoperatively. The majority of IHs in BPD‐DS patients were in the pseudo‐Petersen's space. The single IH case in the SADI‐S group occurred in the same space. Most patients presented with abdominal pain and were diagnosed by CT imaging. SADI‐S showed a lower IH rate compared to BPD‐DS, but further studies are needed to confirm these findings. The variability in clinical presentation complicates the diagnosis of IH, emphasizing the need for increased clinical vigilance.
The Influence of Area Deprivation Index on Surgical Outcomes in Pancreas Cancer
Muaddi, Hala , Glasgow, Amy E. , Chaar, Mohamad K. Abou , Habermann, Elizabeth B. , Smoot, Rory L. , Kendrick, Michael L. , Truty, Mark J. , Glasgow, Amy, Abou Chaar, Mohamad K, Habermann, Elizabeth , Kendrick, Michael, Truty, Mark, Smoot, Rory L , Abou Chaar, Mohamad , Starlinger, Patrick , Warner, Susanne G. , Thiels, Cornelius A.

Journal of Surgical Oncology | December 4, 2024 | Volume: 131 | Issue: 5 | Pages: 827-833

10.1002/jso.28002 Get It

ABSTRACT Background Surgical resection for pancreas ductal adenocarcinoma (PDAC) remains the mainstay of treatment. Regardless of enhanced survival rates, disparities in patient outcomes and experiences driven by the social determinants of health (SDH) persist. The area deprivation index (ADI) comprises 17 indicators related to education, employment, housing‐quality, and poverty. We sought to examine the impact of ADI on surgical outcomes of PDAC patients. Methods Patients who underwent pancreatoduodenectomy or distal pancreatectomy for PDAC between January 2011 and December 2022 were identified. ADI was calculated using patient zip codes and categorized into quartiles, with the highest indicating the most marginalized. The primary outcome was loss to follow‐up after surgical resection. To account for confounders, a competing risk multivariable regression analysis was used. Results A total of 1001 patients had a mean age of 66.6 (±9.64), with 46.3% ( n = 463) of patients being female. A majority, 94.6% ( n = 947), identified as white, and 64.1% ( n = 641) had at least a college degree. The median length of follow‐up after surgery was 1.8 years (interquartile range: 0.9–3.5). Multivariable analysis adjusting for competing risk of death, showed that patients who are least marginalized are 1.57 times more likely to have their follow‐up than those most marginalized (hazard ratio: 1.57, 95% confidence interval: 1.08–2.29, p = 0.017). Conclusion SDH impact many aspects of patient's care including a higher risk of loss to follow‐up for marginalized patients after surgery for PDAC. Future efforts should seek to identify and lower barriers faced by marginalized patients with system‐level changes to ensure equitable access.
Accuracy of DOTATATE PET imaging in the preoperative planning of small bowel neuroendocrine tumor resection
Zhang, Chi , Gudmundsdottir, Hallbera , Takahashi, Hiroaki , Day, Courtney N. , Glasgow, Amy E. , Wasif, Nabil , Grotz, Travis E. , Smoot, Rory L. , Truty, Mark J. , Kendrick, Michael L. , Nagorney, David M. , Grotz, Travis E , Truty, Mark, Cleary, Sean, Kendrick, Michael, Nagorney, David, Navin, Patrick, Thiels, Cornelius A , Smoot, Rory L , Gudmundsdottir, Hallbera , Takahashi, Hiroaki , Starlinger, Patrick , Warner, Susanne G. , Cleary, Sean P. , Navin, Patrick J. , Hálfdánarson, Þorvarður R. , Thiels, Cornelius A.

Journal of Surgical Oncology | August 2, 2023 | Volume: 128 | Issue: 7 | Pages: 1072-1079

10.1002/jso.27413 Get It

AbstractBackground and ObjectivesWe assessed the accuracy of preoperative gallium‐68 DOTA‐Tyr3‐octreotate (DOTATATE) positron emission tomography (PET) imaging in estimating multifocality and nodal metastases of small bowel neuroendocrine tumors (sbNETs).MethodsA multicenter analysis was performed on patients with sbNETs who underwent preoperative DOTATATE PET imaging and surgical resection, with manual palpation of the entire length of the small bowel, between January 2016 and August 2022. Preoperative imaging reports and blinded secondary imaging reviews were compared to the final postoperative pathology reports. Descriptive statistics were applied.ResultsOne‐hundred and four patients met inclusion criteria. Pathology showed 53 (51%) patients had multifocal sbNETs and 96 (92%) had nodal metastases. The original preoperative DOTATATE PET imaging identified multifocal sbNET in 28 (27%) patients and lymph node (LN) metastases in 80 (77%) patients. Based on original radiology reports, sensitivity for multifocal sbNET identification was 45%, specificity was 92%, positive predictive value (PPV) was 86%, and negative predictive value (NPV) was 62%. For the identification of LN metastases, sensitivity was 82%, specificity was 88%, PPV was 99%, and NPV was 29%.ConclusionsAlthough DOTATATE PET imaging is specific and relatively accurate, sensitivity and NPV are insufficient to guide surgical planning. Preoperative use should not replace open palpation to identify additional synchronous lesions or to omit regional lymphadenectomy.
Quality of Life and Gastrointestinal Symptoms in Long-term Survivors of Pancreatic Cancer Following Pancreatoduodenectomy
Zhang, Chi , Smoot, Rory L. , Kendrick, Michael L. , Truty, Mark J. , Zironda, Andrea , Kendrick, Michael, Cleary, Sean, Truty, Mark, Smoot, Rory L , Vierkant, Robert A. , Starlinger, Patrick , Warner, Susanne G. , Cleary, Sean P. , Thiels, Cornelius A.

Annals of Surgery | July 27, 2023 | Volume: 279 | Issue: 5 | Pages: 842-849

10.1097/sla.0000000000006053 Get It

Objective: To describe long-term quality of life (QOL) and gastrointestinal (GI) symptoms in patients who underwent pancreatoduodenectomy for pancreatic cancer in the modern era. Background: As advances in pancreatic cancer management improve outcomes, it is essential to assess long-term patient-reported outcomes after surgery. Methods: Patients who underwent curative intent pancreatoduodenectomy for pancreatic cancer between January 2011 and June 2019 from a single center were identified. Patients alive ≥3 years after surgery were considered long-term survivors (LTS). LTS who were alive in June 2022 received a 55-question survey to assess their QOL (EORTC-QLQ-C30) and GI symptoms (EORTC-PAN26 and Problem Areas in Diabetes Questionnaire). Responses were compared against population norms. Clinicodemographic characteristics in LTS versus non-LTS and survey completion were compared. Results: Six hundred seventy-two patients underwent pancreatoduodenectomy for pancreatic cancer; 340 were LTS. One hundred thirty-seven patients of the 238 eligible to complete the survey responded (response rate: 58%). Compared to the US general population, LTS reported significantly higher QOL (75 vs 64; P<0.001), less nausea/vomiting, pain, dyspnea, insomnia, appetite loss, and constipation, but more diarrhea (all P<0.001). Most patients (n=136/137, 99%) reported experiencing postoperative GI symptoms related to pancreatic insufficiency (n=71/135, 53%), reflux (n=61/135, 45%), and delayed gastric emptying (n=31/136, 23%). Most patients (n=113/136, 83%) reported that digestive symptoms overall had little to no impact on QOL, and 91% (n=124/136) would undergo surgery again. Conclusions: Despite known long-term complications following pancreatoduodenectomy, cancer survivors appear to have excellent QOL. Specific long-term gastrointestinal symptoms data should be utilized for preoperative education and follow-up planning.
Risk of non-hormonal cancer after bariatric surgery: meta-analysis of retrospective observational studies
Clapp, Benjamin , Portela, Ray , Sharma, Ishna , Nakanishi, Hayato , Marrero, Katie , Dayyeh, Barham Abu, Kendrick, Michael, Ghanem, Omar M. , Abu Dayyeh, Barham, Schauer, Philip R , Hálfdánarson, Þorvarður R.

British Journal of Surgery | October 4, 2022 | Volume: 110 | Issue: 1 | Pages: 24-33

10.1093/bjs/znac343 Get It

Abstract Background Obesity is associated with an increased incidence of at least 13 types of cancer. Although bariatric surgery has been associated with a reduced risk of hormonal cancers, data for non-hormonal cancers are scarce. The aim of this study was to evaluate the effect of bariatric surgery on the incidence of non-hormonal cancers. Methods Cochrane, Embase, PubMed, Scopus, and Web of Science were searched for articles between 1984 and 2018, following the PRISMA system. Meta-analysis was conducted using a random-effect model with subgroup analysis by procedure and cancer type. Results From 2526 studies screened, 15 were included. There were a total of 18 583 477 patients, 947 787 in the bariatric group and 17 635 690 in the control group. In comparison to the non-surgical group, the bariatric group had a lower incidence of cancer (OR .65 (95 per cent c.i. 0.53 to 0.80); P &lt; 0.002). In the subgroup analysis, Roux-en-Y gastric bypass and sleeve gastrectomy were associated with decreased risk of developing cancer, while no difference was observed with adjustable gastric banding. When evaluated by cancer type, liver (OR 0.417 (95 per cent c.i. 0.323 to 0.538)), colorectal (OR 0.64 (95 per cent c.i. 0.49 to 0.84)), kidney and urinary tract cancer (OR 0.77 (95 per cent c.i. 0.72 to 0.83)), oesophageal (OR 0.60 (95 per cent c.i. 0.43 to 0.85)), and lung cancer (OR 0.796 (95 per cent c.i. 0.45 to 0.80)) also presented a lower cancer incidence in the bariatric group. Conclusion Bariatric surgery is related to an almost 50 per cent reduction in the risk of non-hormonal cancers.
Cyclooxygenase-2 and Cytosolic Phospholipase A2 Are Overexpressed in Mucinous Pancreatic Cysts
Mensah, Elsie T., Smyrk, Thomas C. , Zhang, Lizhi , Bick, Benjamin L. , Wood‐Wentz, Christina M. , Buttar, Navtej , Chari, Suresh T. , Gleeson, Ferga C. , Kendrick, Michael L. , Pearson, Randall K., Petersen, Bret T. , Vege, Santhi Swaroop , Topazian, Mark , Bick, Benjamin, Kendrick, Michael, Pearson, Randall, Vege, Santhi, Enders, Felicity , Limburg, Paul, Lévy, Michaël , Limburg, Paul J. , Chari, Suresh T

Clinical and Translational Gastroenterology | April 21, 2019 | Volume: 10 | Issue: 4 | Pages: e00028

10.14309/ctg.0000000000000028 Get It

OBJECTIVES: Expression of prostaglandin biosynthetic pathway enzymes in mucinous pancreatic cysts is unknown. Cyclooxygenase-2 (COX-2) inhibition is a potential cancer chemoprevention strategy for these lesions. We evaluated the expression of COX-2, cytosolic phospholipase A2 (cPLA2), and protein kinase B (AKT) in the epithelium of pancreatic cysts and correlated enzyme expression with aspirin (ASA) use and cyst fluid prostaglandin E 2 (PGE 2 ) concentration. METHODS: Pathology of 80 resected pancreatic cysts was reviewed. Expression of COX-2, cPLA2, and AKT was quantified by tissue immunohistochemistry immunoreactivity scores (IRSs). IRS values were compared between cyst types and (in 30 cases) with matched cyst fluid PGE 2 concentrations. RESULTS: The mean IRS was higher in the epithelium of mucinous vs nonmucinous cysts for COX-2 (6.1 ± 4.7 vs 3.2 ± 2.8, P = 0.01) and cPLA2 (6.9 ± 3.0 vs 2.9 ± 2.9, P < 0.001). Cyst epithelial COX-2 expression was higher in mucinous cysts with low-grade dysplasia vs those with high-grade dysplasia or invasive carcinoma (IRS 8.0 ± 3.9 vs 1.5 ± 2.9, P < 0.001), whereas the opposite was found for cPLA2 (6.2 ± 3.0 vs 8.6 ± 2.3, P = 0.005). Cyst fluid PGE 2 concentrations did not correlate with either the IRS or a history of low- to moderate-dose ASA use. CONCLUSIONS: COX-2 and cPLA2 are overexpressed in the epithelium of mucinous pancreatic cysts. COX-2 and/or cPLA2 inhibition might prevent the emergence or progression of mucinous pancreatic cysts, but higher doses of ASA or nonsteroidal anti-inflammatory drugs may be necessary to substantially inhibit cyst epithelial COX-2 activity.