[Cephalic pancreaticoduodenectomy for adenocarcinoma of the head of the pancreas: does pylorus preservation change morbidity and prognosis?]

The effect of pylorus removal on delayed gastric emptying after pancreaticoduodenectomy: a meta-analysis of 2,599 patients

BACKGROUND

Delayed gastric emptying is a serious complication of pancreaticoduodenectomy. The effect of pylorus removal on delayed gastric emptying has not been well evaluated.

STUDY DESIGN

We searched five databases (PubMed, EMBASE and the Cochrane Central Register of Controlled Trials, Scopus and Web of Science) up to July 2014. The meta-regression analysis was performed to evaluate any factors accountable for the heterogeneity. Publication bias was assessed by Egger's test, and corrected by Duval's trim and fill method. Subgroup analyses were conducted for different surgical techniques of pyloric removal. Other intraoperative and postoperative parameters were compared between two groups.

RESULTS

We included 27 studies involving 2,599 patients, with a moderate-high heterogeneity for primary outcome (I(2) = 63%). Meta-regression analysis showed that four variables primarily contributed to the heterogeneity, namely nasogastric tube intubation time, solid food start time, preoperative diabetes percentage and the number of patients in pylorus-preserving group. After excluding four studies, the remaining twenty-three studies showed reduced heterogeneity (I(2) = 51%). Then we used Duval's trim and fill method to correct publication bias. The corrected MH odds ratio was 0.78 (95% CI: 0.52-1.17). A subgroup analysis showed that pylorus removal tends to reduce delayed gastric emptying incidence for subtotal stomach-preserving pancreaticoduodenectomy or pylorus-resecting pancreaticoduodenectomy, compared with pylorus-preserving group. However, standard Whipple procedure failed to show any significant reduction of DGE compared with pylorus-removal group. No significant differences were observed in terms of length of hospital stay, infection and pancreatic fistula; however, pylorus removal resulted in longer operation time, more blood loss and higher mortality.

CONCLUSION

The pylorus removal does not significantly reduce the overall incidence of delayed gastric emptying. Subtotal stomach-preserving pancreaticoduodenectomy or pylorus-resecting pancreaticoduodenectomy tends to reduce delayed gastric emptying incidence, but needs further validation.

[Survival, mortality and quality of life after pylorus-preserving or classical Whipple operation. A systematic review with meta-analysis]

BACKGROUND

Two surgical procedures are mainly performed for the treatment of pancreatic head cancer and periampullary carcinoma: the classical Whipple operation and the pylorus-preserving Whipple operation.

METHODS

This manuscript represents an extension of a systematic review and meta-analysis previously published in the Annals of Surgery. A systematic literature search was performed in MEDLINE, EMBASE and the Cochrane Library (central) to identify randomized controlled trials (RCTs) and observational studies. A meta-analysis based on a random-effects model was performed for the hazard ratios (HR) of survival and the odds ratios (OR) of postoperative mortality. The results of the different studies on quality of life (QoL) could not be summarized quantitatively in a meta-analysis and were therefore summarized qualitatively. Subgroup analyses were performed by study type, RCTs, prospective cohort studies (PSs), retrospective cohort studies (RSs), study quality and tumor localization (pancreatic head cancer versus periampullary carcinoma).

RESULTS

The systematic literature search retrieved 4,503 studies of which 4,460 did not fulfill the inclusion criteria. The remaining 43 studies (6 RCTs, 12 PSs and 25 RSs) representing 3,893 patients were finally included in the review. There was neither a significant survival difference for patients with pancreatic head cancer in the pooled estimate of the RCTs (HR 0.80; 95% CI 0.53-1.22; p=0.16) nor in the pooled estimate of the PSs (HR 0.84; 95% CI 0.7-1.0; p=0.95) or the RSs (HR 0.84; 95% CI 0.7-1.01; p=0.21). Survival of patients with periampullary carcinoma was not significantly different in the RCTs (HR 1.02; 95% CI 0.49-2.13; p=0.3), the PSs (HR 1.26; 95% CI 0.46-3.42; p=0.65) or the RSs (HR 0.86; 95% CI 0.6-1.24; p=0.33). Postoperative mortality was not significantly different after both types of operations (RCTs: HR 0.49; 95% CI 0.17-1.4; p=0.18; PSs: HR 0.63; 95% CI 0.34-1.18; p=0.15; RSs: HR 0.7; 95% CI 0.37-1.31; p=0.27). QoL was reported as either the same in both groups or in favor of the pylorus-preserving Whipple operation.

CONCLUSIONS

Mortality, survival and QoL were not significantly different between the classical Whipple and the pylorus-preserving Whipple operations. Given the poor quality of the underlying trials a pragmatic RCT is recommended to prove the findings of this systematic review.