***TASK*** the task is to summarize an input biomedical literature in six sentences 
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    Input: BACKGROUND For patients with chronic pancreatitis and a dilated pancreatic duct , ductal decompression is recommended . We conducted a r and omized trial to compare endoscopic and surgical drainage of the pancreatic duct . METHODS All symptomatic patients with chronic pancreatitis and a distal obstruction of the pancreatic duct but without an inflammatory mass were eligible for the study . We r and omly assigned patients to undergo endoscopic transampullary drainage of the pancreatic duct or operative pancreaticojejunostomy . The primary end point was the average Izbicki pain score during 2 years of follow-up . The secondary end points were pain relief at the end of follow-up , physical and mental health , morbidity , mortality , length of hospital stay , number of procedures undergone , and changes in pancreatic function . RESULTS Thirty-nine patients underwent r and omization : 19 to endoscopic treatment ( 16 of whom underwent lithotripsy ) and 20 to operative pancreaticojejunostomy . During the 24 months of follow-up , patients who underwent surgery , as compared with those who were treated endoscopically , had lower Izbicki pain scores ( 25 vs. 51 , P<0.001 ) and better physical health summary scores on the Medical Outcomes Study 36-Item Short-Form General Health Survey question naire ( P=0.003 ) . At the end of follow-up , complete or partial pain relief was achieved in 32 % of patients assigned to endoscopic drainage as compared with 75 % of patients assigned to surgical drainage ( P=0.007 ) . Rates of complications , length of hospital stay , and changes in pancreatic function were similar in the two treatment groups , but patients receiving endoscopic treatment required more procedures than did patients in the surgery group ( a median of eight vs. three , P<0.001 ) . CONCLUSIONS Surgical drainage of the pancreatic duct was more effective than endoscopic treatment in patients with obstruction of the pancreatic duct due to chronic pancreatitis . ( Current Controlled Trials number , IS RCT N04572410 [ controlled-trials.com ] . ) OBJECTIVE This study evaluated the effect of operative drainage of the main pancreatic duct ( MPD ) on functional derangements associated with chronic pancreatitis ( CP ) . SUMMARY BACKGROUND DATA The author previously reported delayed functional impairment in an evaluation of the impact of operative drainage in patients with CP . The author now reports on a prospect i ve study of 143 patients with this diagnosis . METHODS Each patient underwent 1 ) ERCP , 2 ) the Bentiromide PABA ,  3 ) 72-hour fecal fat test , 4 ) oral glucose tolerance test ( OGTT ) and 5 ) fat meal (LIPOMUL)--stimulated pancreatic polypeptide release ( PP ) . All patients were stratified as mild/moderate ( M/M ) or severe CP on the basis of a 5-point system that was developed by the author . Patients were studied at 16-month intervals . RESULTS All 143 patients underwent initial and follow-up evaluations in a mean follow-up of 47.3 months ; 83 of 143 patients had M/M grade at initial evaluation . Eighty-seven patients underwent ( MPD ) decompression to relieve abdominal pain . In a separate prospect i ve 17 patients with a diagnosis of CP , a grade of M/M and non-disabling abdominal pain were r and omized to operative or non-operative treatment ; 9 of these r and omized patients were operated upon and 8 were not . No patient improved their grade during follow-up ; 47 of 83 M/M patients had operative drainage and 36 did not . This grade was preserved in 41 of 47 ( 87 % ) operated patients but in only 8 of the 36 non-operated patients ( 22 % ) . In the r and omized trial , seven of nine operated patients retained their functional status in follow-up , whereas only two of eight patients ( 25 % ) r and omized to non-operation preserved their functional grade . CONCLUSIONS These data in this large study as well as among a previous r and omized sample , support a policy of early operative drainage before the development of irreversible functional impairment in patients with chronic pancreatitis and associated dilation of the main pancreatic duct OBJECTIVE To analyze the efficacy of extended drainage -- that is , longitudinal pancreaticojejunostomy combined with local pancreatic head excision (LPJ-LPHE)- and pylorus-preserving pancreatoduodenectomy ( PPPD ) in terms of pain relief , control of complications arising from adjacent organs , and quality of life . SUMMARY BACKGROUND DATA Based on the hypotheses of pain origin ( ductal hypertension and perineural inflammatory infiltration ) , drainage and resection constitute the main principles of surgery for chronic pancreatitis . METHODS Sixty-one patients were r and omly allocated to either LPJ-LPHE ( n = 31 ) or PPPD ( n = 30 ) . The interval between symptoms and surgery ranged from 12 months to 10 years ( mean 5.1 years ) . In addition to routine pancreatic diagnostic workup , a multidimensional psychometric quality -of-life question naire and a pain score were used . Endocrine and exocrine functions were assessed in terms of oral glucose tolerance and serum concentrations of insulin , C-peptide , and HbA1c , as well as fecal chymotrypsin and pancreolauryl testing . During a median follow-up of 24 months ( range 12 to 36 ) , patients were reassessed in the outpatient clinic . RESULTS One patient died of cardiovascular failure in the LPJ-LPHE group ( 3.2 % ) ; there were no deaths in the PPPD group . Overall , the rate of in-hospital complications was 19.4 % in the LPJ-LPHE group and 53.3 % in the PPPD group , including delayed gastric emptying in 9 of 30 patients ( 30 % ; p < 0.05 ) . Complications of adjacent organs were definitively resolved in 93.5 % in the LPJ-LPHE group and in 100 % in the PPPD group . The pain score decreased by 94 % after LPJ-LPHE and by 95 % after PPPD .  Global quality of life improved by 71 % in the LPJ-LPHE group and by 43 % in the PPPD group ( p < 0.01 ) . CONCLUSIONS Both procedures are equally effective in terms of pain relief and definitive control of complications affecting adjacent organs , but extended drainage by LPJ-LPHE provides a better quality of life Background This study aim ed to compare the outcomes of endoscopic treatment ( ET ) and surgical treatment ( ST ) for common bile duct ( CBD ) stricture in patients with chronic pancreatitis ( CP ) . Methods From 2004 to 2009 , 39 patients ( 35 men and 4 women ; median age , 52 years ; range , 38–66 years ) were referred for CBD stricture in CP . Of these 39 patients , 33 ( 85 % ) underwent primary ET , and 6 underwent primary ST . Treatment success was defined in both groups as the absence of signs denoting recurrence , with normal serum bilirubin and alkaline phosphatase levels after permanent stent removal in ET group . The follow-up period was longer than 12 months for all the patients . Results For the patients treated with ET , the mean number of biliary procedures was 3 ( range , 1–10 ) per patient including extractible metallic stents in 35 % and multiple plastic stents in 65 % of the patients . The mean duration of stent intubation was 11 months . The surgical procedure associated with biliary drainage ( 4 choledochoduodenostomies , 1 choledochojejunostomy , and 1 biliary decompression within the pancreatic head ) was a Frey procedure for five patients and a pancreaticojejunostomy for one patient . The overall morbidity rate was higher in the ST group . The total hospital length of stay was similar in the two groups ( 16 vs 24 days , respectively ; p = 0.21 ) . In terms of intention to treat , the success rates for ST and ET did not differ significantly ( 83 % vs 76 % ; p = 0.08 ) . Due to failure , 17 patients required ST after ET . Event-free survival was significantly longer in the ST group ( 16.9 vs 5.8 months ; p = 0.01 ) . The actuarial success rates were 74 % at 6 months , 74 % at 12 months , and 65 % at 24 months in the ST group and respectively 75 % , 69 % , and 12 % in the ET group ( p = 0.01 ) . After more than three endoscopic procedures , the success rates were 27 % at 6 months and 18 % at 18 months . Conclusion For bile duct stricture in CP , surgery is associated with better long-term outcomes than endoscopic therapy . After more than three endoscopic procedures , the success rate is low This paper discusses the various philosophies that influence the selection of patients for entry into r and omized controlled trials .  Although a number of different and often competing issues have to be considered depending upon the trial , keeping entry criteria simple , wide and at times even flexible is usually preferable . Such a strategy can be a positive virtue by helping to attain the large numbers of patients that are usually needed to reliably detect the sorts of moderate benefits that are plausible , at a reasonable cost and by providing answers that are relevant to many different categories of patients with a particular condition Background A number of studies support the use of endoscopically placed pancreatic duct ( PD ) stents to decrease pain in chronic pancreatitis ( CP ) . Nevertheless , flaws in study design have prevented experts from reaching a consensus . Purpose ( 1 ) Evaluate the efficacy of PD stenting to ameliorate abdominal pain in patients with CP and ductal strictures ; ( 2 ) evaluate the placebo response rate from sham endoscopic therapy ; ( 3 ) compare pain medication usage , healthcare utilization , psychological distress , and quality of life before and after endoscopic stenting ; ( 4 ) prospect ively evaluate the durability of the response . Methods Patients with typical abdominal pain , imaging confirmation of CP and endoscopic retro grade cholangiopancreatography ( ERCP ) confirmation of PD stricture will complete question naires to assess quality of life , psychological distress , pain intensity/unpleasantness , pain medication usage , and healthcare utilization . Enrolled patients will be r and omized to ERCP with sphincterotomy and PD stenting versus sham procedure .  Pain level and medication usage will be assessed weekly with telephone interviews . At 6—8 weeks , patients treated with stents will undergo stent removal ; those r and omized to the sham procedure without significant improvement ( < 50 % reduction in pain score ) will cross over to the treatment group ; and those r and omized to sham procedure who experienced improvement ( > 50 % reduction ) will be followed clinical ly . Patients will be followed in clinic or by phone biannually ( up to 3 years ) . The primary endpoint is improvement in abdominal pain . The secondary endpoints are reduction in narcotic use , healthcare utilization , and work days missed ; return to employment ; improvement in quality of life and weight gain . Results Proposed study . Limitations Strict inclusion criteria may limit enrollment . Conclusion The proposed study represents the first trial of endoscopic stenting for symptomatic CP and ductal strictures with a credible sham procedure , assessment of multiple dimensions of pain , and psychosocial factors . Clinical Trials 2009 ; 6 : 455—463 . Objective : To report on the long-term follow-up of a r and omized clinical trial comparing pancreatic head resection according to Beger and limited pancreatic head excision combined with longitudinal pancreatico-jejunostomy according to Frey for surgical treatment of chronic pancreatitis . Summary Background Data : Resection and drainage are the 2 basic surgical principles in surgical treatment of chronic pancreatitis . They are combined to various degrees by the classic duodenum preserving pancreatic head resection ( Beger ) and limited pancreatic head excision combined with longitudinal pancreatico-jejunostomy ( Frey ) . These procedures have been evaluated in a r and omized controlled trial by our group . Long-term follow up has not been reported so far . Methods : Seventy-four patients suffering from chronic pancreatitis were initially allocated to DPHR ( n = 38 ) or LE ( n = 36 ) . This postoperative follow-up included the following parameters : mortality , quality of life ( QL ) , pain ( vali date d pain score ) , and exocrine and endocrine function . Results : Median follow-up was 104 months ( 72 - 144 ) . Seven patients were not available for follow-up ( Beger = 4 ; Frey = 3 ) . There was no significant difference in late mortality ( 31 % [ 8/26 ] versus 32 % [ 8/25 ] ) . No significant differences were found regarding QL ( global QL 66.7 [ 0–100 ] versus 58.35 [ 0–100 ] ) , pain score ( 11.25 [ 0–75 ] versus 11.25 [ 0–99.75 ] ) , exocrine ( 88 % versus 78 % ) or endocrine insufficiency ( 56 % versus 60 % ) . Conclusions : After almost 9 years ’ long 
    Output:
    
The trial showed that surgical intervention result ed in a higher percentage of participants with pain relief and better preservation of pancreatic function .
For patients with obstructive chronic pancreatitis and dilated pancreatic duct , this review shows that surgery is superior to endoscopy in terms of pain relief .
Morbidity and mortality seem not to differ between the two intervention modalities , but the small trials identified do not provide sufficient power to detect the small differences expected in this outcome .Regarding the comparison of surgical intervention versus conservative treatment , this review has shown that surgical intervention in an early stage of chronic pancreatitis is a promising approach in terms of pain relief and pancreatic function .