stained positive for cytokeratin 19, confirm- ing their epithelial origin (Fig. 1E). How- ever, the former expressed MUC5AC and the latter did not stain for this marker. In conclusion, forced expression of constitu- tive active IKKβ in the pancreatic epithe- lium accelerates Kras G12D driven tumor formation. This study was supported in part by grants from National Institutes of Health (CA182820, CA197999, CA054807, and CA127297). The authors declare no conflict of interest. Mayumi Naramura, MD Amarnath Natarajan, PhD Eppley Institute for Cancer Research Fred & Pamela Buffett Cancer Center University of Nebraska Medical Center Omaha, NE anatarajan@unmc.edu REFERENCES 1. Tuveson DA, Hingorani SR. Ductal pancreatic cancer in humans and mice. Cold Spring Harb Symp Quant Biol. 2005;70:65–72. 2. Midha S, Chawla S, Garg PK. Modifiable and non-modifiable risk factors for pancreatic cancer: a review. Cancer Lett. 2016;38:269–277. 3. Daniluk J, Liu Y, Deng D, et al. An NF-κB pathway-mediated positive feedback loop amplifies Ras activity to pathological levels in mice. J Clin Invest. 2012;122:1519–1528. 4. Ling J, Kang Y, Zhao R, et al. KrasG12D- induced IKK2/β/NF-κB activation by IL-1α and p62 feedforward loops is required for development of pancreatic ductal adenocarcinoma. Cancer Cell. 2012;21: 105–120. 5. Maniati E, Bossard M, Cook N, et al. Crosstalk between the canonical NF-κB and Notch signaling pathways inhibits Pparγ expression and promotes pancreatic cancer progression in mice. J Clin Invest. 2011;121:4685–4699. Dakin Solution for Irrigation of Pancreatic Fluid Collections To the Editor: T he treatment of necrotizing pancreatitis has evolved from surgical management with pancreatic necrosectomy to image- guided percutaneous drainage as a first line procedure while reserving surgery for those who fail conservative management. 1 Guide- lines on catheter irrigation are broad, and irrigation is usually with normal or diluted saline. 2 To our knowledge, there are no previous studies that describe Dakin solu- tion as an irrigant in pancreatic drainage and very few overall studies that address it as an intra-abdominal irrigant. The purpose of our study was to evaluate the safety and efficacy of Dakin solution for irrigation of pancreatic fluid collections (PFCs). This was an institutional review board–approved retrospective study, which included all patients with pancreatitis complicated by PFC who underwent image-guided catheter drainage over a pe- riod of 7 years at a single institution. Of the 83 patients, 5 were lost to follow-up. A total of 78 patients were considered for Dakin safety and efficacy, drainage success, drainage failure, and PFC recurrence. Com- puted tomography of the abdomen and pelvis was used for the diagnosis of PFC in all patients. Drainage indications were pain, sepsis, or biliary obstruction. Single (17 patients) or multiple (62 patients) cath- eters were used for drainage. Follow-up included irrigation with Dakin solution 1 to 4 times per day. Parameters evaluated were patient discomfort, evidence of mal- odorous discharge, substantial serum elec- trolyte abnormalities (particularly sodium, chlorine, and carbon dioxide), removal of necrotic debris, clearance of local infection, drainage success with PFC resolution with catheter drainage, recurrent collections, drainage failure, and mortality. Dakin solution was well tolerated with no patient discomfort or malodorous dis- charge. Postprocedure electrolytes were ob- tained in 70 (90%) of 78, and there were no substantial electrolyte abnormalities in any patient. The irrigant was effective in all (78/78 patients), with a reduction in ne- crotic debris during the irrigation period and a clearance of local infection in all 78 pa- tients. Percutaneous drainage alone achieved PFC resolution in 69 (88%) of 78 patients. Pancreatic fluid collection recurred in 12 (15%) of 78 patients. Drainage failure oc- curred in 9 (12%) of 78 patients. Surgery was carried out in 2 (3%) of 78 patients (necrosectomy and surgical drainage). Seven patients (9%) died: 5 patients died of multiorgan failure, 1 of pulmonary embo- lism, and 1 patient of intracranial hemorrhage. Dakin solution is an antiseptic mixture containing dilute sodium hypochlorite (the primary ingredient of household bleach) that was first developed during the preantibiotic World War I era to treat wound infections. 3 Developed by bio- chemist Henry Drysdale Dakin and surgeon Alexis Carrel, more than 200 substances were tested before choosing buffered hypo- chlorite of soda as the preferred antiseptic substance because of its minimal tissue toxicity and superior wound sterilization capabilities. 4 Dakin solution became the primary method for wound treatment until antibiotics were introduced and available during World War II. 3 However, emergence of antibiotic resistance in the 1980s prompted renewed interest in Dakin solution, and vari- ous concentrations of the solution became commercially available. “Full-strength” Dakin solution is provided as a 0.5% sodium hy- pochlorite and considered the highest con- centration tolerable to skin as recommended by the Centers for Disease Control and Pre- vention. More dilute concentrations include 0.25%, 0.125%, and 0.0125% sodium hypo- chlorite. More dilute solutions are less toxic to normal cells involved in wound healing such as neutrophils and fibroblasts. 5 The use of Dakin solution other than solely as a topical agent for wound infec- tions has been infrequently described. For example, from the early 1920s until the be- ginning of the antibiotic era in the 1940s, Dakin solution was used for the treatment of thoracic empyema. 6,7 Few studies report Dakin solution as an intra-abdominal irrigant. Parcells et al 8 described an analysis of 1063 adult appendectomies and compared rates of postoperative overall surgical site infection, wound infection, and abdominal abscess following the use of normal saline (0.9%), Dakin solution (0.25% sodium hypochlo- rite), or an antibiotic solution (imipenem 1 mg/mL) as intraoperative irrigation solu- tions. In that study, Dakin solution appeared to be inferior to both normal saline and imipenem with respect to the percentage of cases affected regarding all 3 parame- ters of postoperative infection. Importantly, preclinical studies—both in vitro (exam- ining fibroblasts, mesothelial cells, and polymorphonuclear leukocytes in culture) 9 and in vivo (examining peritoneal injury in rats following intraperitoneal injection of Dakin solution) 10 —suggest Dakin solu- tion to be safe, although possible adverse concentration-dependent effects on normal cellular functions (eg, cell migration, re- lease of oxygen free radicals) do occur. Saline or other irrigants were not used as a control in this study, and it is unknown how saline and Dakin compared with re- spect to PFCs. The retrospective nature of this study is another limitation. In con- clusion, Dakin solution was safe and well suited for irrigation during image-guided catheter drainage of PFCs in patients with pancreatitis. A preliminary version of this study was presented at the Society of Interven- tional Radiology Annual Scientific Meeting in San Diego, CA, as follows: Beck CJ, D'Agostino HB, Vea R, Pilat M, Maranto Pancreas • Volume 47, Number 5, May/June 2018 Letters to the Editor © 2018 Wolters Kluwer Health, Inc. All rights reserved. www.pancreasjournal.com e29 Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.