[Current indications for pylorus saving duodenopancreatic head resection in malignancy]

[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.

Peripyloric lymph node metastasis is a rare condition in carcinoma of the pancreatic head

OBJECTIVES

Pylorus preserving pancreatoduodenectomy (PPPD) was introduced to achieve a better functional result compared with the conventional Kausch-Whipple procedure (PD). In PPPD, peripyloric and perigastric lymphatic tissue is not removed compared with PD. The aim of this prospective study was to identify the frequency of peripyloric and perigastric lymph node metastases in ductal adenocarcinoma of the pancreatic head (PC).

METHODS

Fifty specimens following Kausch-Whipple procedure including partial gastric resection for PC were analyzed for peripyloric and perigastric lymph node metastases by a standardized clearing technique. All lymph nodes of the specimens were counted, discriminating between those not removed ("group A") and those removed ("group B") in pylorus preserving resection of the pancreatic head. Additionally, the duodenal wall and paraduodenal tissue at a potential duodenal resection margin 2 cm distal of the pylorus were investigated histologically.

RESULTS

Three of the 50 specimens (6%) carried peripyloric lymph node metastases, whereas 32 of the 50 specimens (64%) contained lymph node metastases in total. Four of 362 group A and 90 of 748 group B lymph nodes showed metastatic spread of the carcinoma. The 4 lymph node metastases in group A could be identified exclusively in 88 peripyloric lymph nodes but in none of the 274 perigastric lymph nodes at the lesser or greater curvature. In 2 of the 3 patients with peripyloric lymph node metastases, these lymph nodes were the only lymph nodes with metastatic involvement in the entire specimen. In 1 specimen, a small tumor nest of less than 2 mm in diameter was detected at a distance of less than 1 mm to the pylorus, although pyloric involvement was not suspected intraoperatively. The potential PPPD resection margin of the duodenal wall was not infiltrated by intramural tumor spread in any specimen.

CONCLUSION

In a minority of 6%, PC metastasizes in peripyloric lymph nodes. Lymph nodes of the lesser and greater curvature of the stomach are not involved in patients with PC. Thus, we conclude by the data of this prospective study that the limited benefits of the extended lymph node dissection in a conventional Kausch-Whipple resection are far outweighed by the disadvantages construed by this procedure.