***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background : Recurrent acute pancreatitis ( RAP ) and chronic pancreatitis ( CP ) are complex syndromes associated with numerous etiologies , clinical variables and complications . We developed the North American Pancreatitis Study 2 ( NAPS2 ) to be sufficiently powered to underst and the complex environmental , metabolic and genetic mechanisms underlying RAP and CP . Methods : Between August 2000 and September 2006 , a consortium of 20 expert academic and private sites prospect ively ascertained 1,000 human subjects with RAP or CP , plus 695 controls ( spouse , family , friend or unrelated ) . St and ardized question naires were completed by both the physicians and study subjects and blood was drawn for genomic DNA and biomarker studies . All data were double-entered into a data base and systematic ally review ed to minimize errors and include missing data . Results : A total of 1,000 subjects ( 460 RAP , 540 CP ) and 695 controls who completed consent forms and question naires and donated blood sample s comprised the final data set . Data were organized according to diagnosis , supporting documentation , etiological classification , clinical signs and symptoms ( including pain patterns and duration , and quality of life ) , past medical history , family history , environmental exposures ( including alcohol and tobacco use ) , medication use and therapeutic interventions . Upon achieving the target enrollment , data were organized and classified to facilitate future analysis . The approaches , rationale and data sets are described , along with final demographic results . Conclusion : The NAPS2 consortium has successfully completed a prospect i ve ascertainment of 1,000 subjects with RAP and CP from the USA . These data will be useful in elucidating the environmental , metabolic and genetic conditions , and to investigate the complex interactions that underlie RAP and CP OBJECTIVES : Some patients with chronic pancreatitis present recurrent flare-ups of pancreatitis and /or unrelenting pain . Current management is mostly limited to analgesics and surgery . We reasoned that anti-inflammatory radiotherapy , which has proven useful to alleviate other painful inflammatory painful disorders , might prove valuable for severely symptomatic patients with chronic pancreatitis . METHODS : We prospect ively studied the efficacy of single-dose anti-inflammatory radiotherapy in 15 consecutive patients with chronic pancreatitis who fulfilled the following criteria : either two flare-ups of pancreatitis in the previous 6 months and /or continuous pain for more than 3 months . Treatment consisted of a single radiation dose of 8 Gy to the pancreas . Exocrine function ( fecal elastase ) , endocrine function ( c peptide ) , quality of life ( EuroQol question naire ) , and clinical outcome were assessed before and after radiation . Response was defined as no further pain or flare-ups of pancreatitis . RESULTS : During follow-up ( median : 39 months ; range : 4–72 months ) , 12 patients had no further pain or flare-ups . One patient required a second radiation dose 1 year after the initial treatment , but he has remained well ever since ( 50 months ) . Two other patients did not respond to radiotherapy . After radiotherapy either exocrine or endocrine pancreatic function , or both , deteriorated in three patients . Patients who responded to treatment ( 13/15 ) gained 4–20 kg in body weight during follow-up ( median 4 kg ) and EuroQol improved significantly from 0.58 to 0.86 ( P<0.001 ) . CONCLUSIONS : Radiotherapy for severe symptomatic chronic pancreatitis appears to be a useful and effective therapeutic choice that could potentially substitute for or delay surgery BACKGROUND & AIMS The efficacy of endoscopic ultrasound-guided celiac plexus blockade ( EUS-CPB )  for painful chronic pancreatitis ( CP ) is uncertain . Triamcinolone is often mixed with bupivacaine to lengthen the analgesic effect . We investigated whether addition of triamcinolone increases and lengthens pain relief compared with EUS-CPB with only bupivacaine . METHODS We performed a single-center , blinded , r and omized , controlled trial of 40 adult patients referred for EUS-CPB for treatment of painful CP . Patients were assigned r and omly to groups that received EUS-CPB with triamcinolone and bupivacaine or EUS-CPB with only bupivacaine ( control ) . Question naires were collected when the study began ( baseline ) and 1 month later . The primary end point was a decrease in the pain disability index of 10 or more points at 1 month after the procedure . Secondary end points included change in visual analogue scale , narcotic requirements , and quality of life at 1 month . RESULTS There were no significant differences in primary outcomes between groups ( 14.3 % for patients who received triamcinolone vs 15.8 % for controls ; P = .64 ) . The trial was stopped for futility . There was no significant difference between groups in immediate response rates ( 85.7 % for patients who received triamcinolone vs 68.4 % for control ; P = .10 ) , or other secondary end points , including change in pain visual analogue scale ( 0.4 vs 1.0 ; P = .83 ) , treatment with morphine equivalents at 1 month ( -7.8 vs 0.0 ; P = .35 ) , change in quality of life at 1 month ( SF-12 mental component : 1.3 vs -2.1 ; P = .44 ; and physical component : -0.2 vs 1.7 ; P = .54 ) , or adverse events . The duration of response was shorter in the triamcinolone group ( mean , 5.3 vs 0.6 mo ; P = .01 ) . CONCLUSIONS Triamcinolone does not increase pain relief or lengthen the effects of EUS-CPB BACKGROUND This study was aim ed to investigate the effect of long-term treatment with high-protease pancreatic extract on the recurrent abdominal pain of patients with chronic pancreatitis . METHODS Twenty-six patients with a firm diagnosis of chronic pancreatitis and a pattern of recurrent pain were recruited and r and omly assigned to treatment with pancreatic extract ( Pancrex-Duo capsules , each containing 34,375 USP units of protease in enteric-coated microspheres ) or placebo , at a dose of four capsules four times daily , for 4 months . At the end of the first period patients were switched to the other medication for the next 4 months . Four patients did not complete the study because of unbearable recurring pain or inadequate compliance with treatment . The other 22 patients daily recorded the presence , intensity , and duration of pain and the consumption of analgesics , for 8 months . RESULTS No difference was found when intraindividual records during placebo and extract treatment periods were compared . Conversely , in the second 4 months of follow-up , regardless of the treatment given in the first period , there was a significant reduction in the cumulative pain score ( median , 95 ; range , 0 - 1005 , versus 134 ; 0 - 972 ; p < 0.05 ) , in the number of days ( 8 ; 0 - 132 , versus 13 ; 0 - 126 ; p < 0.02 ) and hours ( 54 ; 0 - 680 , versus 80 ; 0 - 602 ; p < 0.05 ) of pain , and in the analgesic consumption score ( 0 ; 0 - 22 , versus 12 ; 0 - 44 ; p = 0.02 ) . CONCLUSIONS Chronic supplementation with pancreatic extract is not beneficial in the management of recurrent pain in patients with chronic pancreatitis Controversies in the literature regarding definition , diagnosis , and therapy of chronic pancreatitis may be related in part to differences in the natural history of alcoholic and idiopathic ( nonalcoholic ) chronic pancreatitis . In order to evaluate this problem the long-term course of 205 patients with alcoholic ( 85.4 % with calcifications ) ( group A ) and 82 patients with idiopathic ( nonalcoholic ) chronic pancreatitis ( 76.8 % with calcifications ) ( group B ) has been analyzed prospect ively since 1963 . The patients were studied at regular intervals with particular regard to pain , pancreatic exocrine , and endocrine function and calcifications . The observation time was 2 years or longer in 230 patients with a median observation time of 6.7 years from diagnosis in group A and 10.6 years in group B. In group B over 50 % of the cases had  primary painless chronic pancreatitis . Progressive deterioration of exocrine and endocrine function was observed in both groups . However , in group A the rate of progression of exocrine dysfunction after diagnosis was more rapid and the incidence of diabetes in relation to marked exocrine insufficiency was much higher than in group B. Steatorrhea preceded diabetes in 56 % ( group A ) and 80 % ( group B ) , respectively . Onset of pancreatic calcifications was closely associated with pancreatic exocrine insufficiency in group A in contrast to group B. In addition lasting pain relief occurred spontaneously in about 30 % of patients in group B despite a normal exocrine function for 6 years or longer which is in disaccord with the results in alcoholic chronic pancreatitis . In conclusion group A and B have many features in common , in particular the high incidence of pancreatic calcifications and the progressive pancreatic dysfunction . However , the long-term profile of both groups differs in some important aspects , particularly in the clinical pattern and in the rate of progression of pancreatic dysfunction and morphology . These differences should be appreciated in the discussion of problems regarding definition , diagnosis , and surgical therapy of chronic pancreatitis BACKGROUND Chronic pancreatitis is a chronic inflammatory disorder characterized by progressive fibrosis of pancreatic tissue . The principal symptom is chronic pain result ing in reduced quality of life and inability to work . Short-term follow-up has shown that duodenum-preserving pancreatic head resections ( DPPHRs ) are superior in outcomes to pancreaticoduodenectomy . Therefore , these organ-sparing procedures have gained wide acceptance . This trial was conducted to compare patient outcomes 16 years after treatment for chronic pancreatitis by means of the Beger or the Frey procedure . STUDY DESIGN Seventy-four patients suffering from chronic pancreatitis were r and omly assigned to 2 treatment groups ( Beger n = 38 ) and Frey ( n = 36 ) . The perioperative courses in the r and omized controlled trial and the 8-year follow-up have been reported previously . All participating patients were contacted with a st and ardized , vali date d question naire to evaluate long-term survival , quality of life , pain , and exocrine and endocrine function . RESULTS No significant differences between the 2 groups in terms of quality of life , pain control , or other somatic parameters were detected after a median of 16 years postoperatively . Mortality was comparable after Beger and Frey procedures at 39 % vs 34 % , respectively , with postoperative survivals of 13.0 ± 1.1 years and 13.3 ± 0.9 years , respectively ( p = 0.660 ) . No statistically significant differences were found in rates of endocrine insufficiency ( Beger 87 % vs Frey 86 % ; p = 0.953 ) or exocrine insufficiency ( Beger 77 % vs Frey 83 % ; p = 0.655 ) . CONCLUSIONS Duodenum-preserving resections of the pancreatic head offered good and permanent pain relief and substantially increased quality of life in chronic pancreatitis . Overall , a 16-year long-term follow-up found comparable outcomes for the Beger and Frey procedures BACKGROUND In about 30 % of patients , chronic pancreatitis leads to an inflammatory enlargement of the pancreatic head with subsequent obstruction of the pancreatic duct , common bile duct , and duodenum . METHODS In a prospect i ve , r and omized controlled trial , we compared duodenum-preserving pancreatic head resection ( DPPHR ) with pylorus-preserving Whipple ( PPW ) operation to define the advantages of each operation with regard to ( 1 ) postoperative complications , ( 2 ) glucose tolerance and induction of diabetes mellitus , and ( 3 ) postoperative pain and quality of life up to 6 months after operation for chronic pancreatitis . RESULTS The two study groups of 20 patients were both well balanced with regard to sex , age , history of chronic pancreatitis , and indication for surgery .  Postoperative mortality was zero . After duodenum-preserving and pylorus-preserving resection , morbidity was 15 % and 20 % , respectively . After 6 months , patients who underwent the duodenum-preserving resection had less pain , greater weight gain , a better glucose tolerance , and a higher insulin secretion capacity . CONCLUSION The DPPHR compares favorably with the st and ard PPW operation and should be considered as an alternative procedure in the treatment of chronic pancreatitis BACKGROUND / AIMS Compared with alcoholic pancreatitis , little is known about the natural history of idiopathic pancreatitis . Two hundred forty-nine patients with alcoholic pancreatitis and 66 patients with idiopathic chronic pancreatitis seen at our institution between 1976 and 1982 were investigated . METHODS Records were analyzed retrospectively from the onset of symptomatic disease , and patients were followed up prospect ively until 1985 . Patients with early-onset ( n = 25 ) and late 
    Output:
    
Despite recommendations the aspects of pain assessed were limited and variable between tools .
Validation of these tools in CP patients was limited to quality of life measures .
None of the pain assessment tools evaluated duration of pain and postpr and ial pain .