Prevention of Postoperative Pancreatic Fistula Following Pancreaticoduodenectomy by Preoperative Radiotherapy : a Phase 2 Trial

To assess overall surgical complication rate at W22 (90 days after surgery)

defined as a grade 1 to 5 according to the Dindo-Clavien classification complications occurring within 3 month from surgery

Time frame: Week 22

To assess severe surgical complication rate at W22 (90 days after surgery)

defined as a grade 3 to 5 according to the Dindo-Clavien classification complications occurring within 3 month from surgery

Time frame: Week 22

To assess, during surgery (W10), the hardness of pancreas texture on the specimen after resection with a durometer

determined intraoperatively by Durometer measurement of the radiated and irradiated pancreatic tissue in Shore OO

Time frame: Week 10

To assess, during surgery (W10), the hardness of pancreas texture on the specimen after resection by the surgeon

Determined intraoperatively by the pancreatic surgeon. Texture is scaled as soft/intermediate/hard at W10

Time frame: Week 10

To assess, during surgery (W10), technical difficulties added by radiotherapy, according to the surgeon

Determined by 2 questions * To what extent was the surgery complicated by the radiotherapy? (Answers: 1 - not complicated; 2 - slightly complicated; 3 - clearly complicated; 4 - severely complicated; 5 - impossible) * Did you have to adapt the surgical plan due to the administration of radiotherapy? (Answers: Yes/No)

Time frame: Day of surgery- Week 10

To assess on a pathological point of view the resected specimen at W14

determined by the pathologist by evaluation of macroscopic differences between radiated and irradiated pancreatic tissue. \- The extent and distribution of fibrosis and fat infiltration were evaluated using the score established by Rebours et al. in intra- and extralobular locations

Time frame: Day of surgery-week 14

To assess on a pathological point of view the resected specimen at W14

determined by the pathologist by evaluation of macroscopic differences between radiated and irradiated pancreatic tissue. \- Fibrosis quantification was also assessed by determining the area of collagen using Sirius red staining (as performed in FIBROPANC trial)

Time frame: Day of surgery-week 14

Pancreatic functionnal outcomes at W22 (de novo diabetes)

Determined by \- De novo diabetes : In accordance with French and European recommendations, diabetes is diagnosed if fasting blood glucose is greater than or equal to 1.26 g/L on two occasions, or greater than or equal to 2 g/L at any time of the day, or if HbA1c is greater than 6.5%

Time frame: Week 22

Pancreatic functionnal outcomes at W22 (exocrine pancreatic insufficiency)

Determined by \- Exocrine pancreatic insufficiency: A fecal elastase level \< 100 mg/g stool is commonly accepted for diagnosing severe exocrine pancreatic insufficiency, a fecal elastase level between 100 and 200 mg/g indicates moderate exocrine pancreatic insufficiency, and a level \> 200 mg/g stool rules out exocrine pancreatic insufficiency

Time frame: Week 22

To assess mortality rate at W22

Time frame: Week 22

To assess overall length of hospital stay after surgery

Length of hospital stay between the operation and the day of discharge from hospital

Time frame: Up to Week 34

To assess readmission rate at W22

Proportion of readmission at W22, whatever the cause

Time frame: Week 22

To assess radiation-induced complications rate, overall and by grade at W9, W10, W14, W22, W34

to CTCAE classification (Common Terminology Criteria for Adverse Events), overall and by grade (grade 1 to 5)

Time frame: Week 9, Week 10, Week 14, Week 22 and Week 34

To assess safety of radiotherapy at W9, and W34

Proportion of patients at W9 and W34 who underwent at least one side effects of radiotherapy among gastritis or gastric bleeding

Time frame: Week 9 and Week 34