In this study, DGE independently impaired patients’ nutritional status during the first postoperative period; however, this impact was only discernible before POM three. On POM three and POM six, all nutritional parameters were equivalent between the patients who had DGE and those who did not. DGE’s influence on patients’ nutritional status after SSPPD may be limited to no more than three months, and DGE may not have impaired their long-term condition. This is the first study to investigate the precise effect of DGE on the serial changes of various nutritional markers.
Adjuvant chemotherapy is initiated in patients with PDAC after adequate recovery from surgery [16, 17]. As a result, maintaining patients’ nutritional condition after surgery is critical for initiating and tolerating adjuvant therapy. Matsumoto et al. previously reported that a low serum albumin level could be a predictor of incomplete adjuvant therapy . Given that serum albumin levels at POM one were lower in DGE patients in the current study, the presence of DGE may compromise adjuvant chemotherapy. In fact, a recent retrospective study reported by Futagawa et al. revealed the negative impact of DGE on long-term survival in patients with PDAC . Preventing DGE may be important to improving the prognosis of patients with PDAC after PD. Because the precise effect of DGE on various nutritional markers has received little attention, the findings of our study may aid in further research into the pathophysiology of DGE and its clinical significance.
Kawai et al. reported that at POM 24, patients with DGE had lower serum albumin and prealbumin levels than those without DGE, implying that the impact of DGE on the patients’ nutritional status of persists much longer than what our study revealed . However, their analysis was limited to a single point in time, and data on serial changes in nutritional status were lacking. Furthermore, the study only included 11 DGE patients; hence, the small sample size may have compromised the study’s findings. The disparity between our findings and those reported by Kawai et al. could also be due to differences in surgical procedures. While only the patients who underwent SSPPD were included in our study, the majority of patients who experienced DGE in the study by Kawai et al. underwent PPPD. As a result, preservation of the pylorus might have influenced the duration of DGE.
Several studies have attempted to elucidate the pathophysiology of DGE after PD [7–11]. Surgical procedure modifications such as pylorus resection, antecolic alimentary tract reconstruction, addition of Braun anastomosis, and Roux-en-Y reconstruction have been reported as possible solutions to reduce DGE, though the impact of these modifications on DGE is still controversial [8–11, 21, 22]. In the current study, it was discovered that stapled gastrojejunostomy was associated with less DGE than hand-sewn anastomosis. Several studies have shown that stapled anastomosis of gastro/duodenojejunostomy is superior to hand-sewn anastomosis in terms of DGE incidence after PD [23–25]. However, the majority of patients in previous studies underwent PPPD, and reports on SSPPD or conventional PD were scarce. The diameter of the anastomotic lumen, the stapling device (circular stapler or linear stapler), and the presence/absence of the pylorus ring were all significantly different between gastro/duodenojejunostomy within SSPPD and PPPD. Thus, mechanisms that may explain the superiority of stapled anastomosis over hand-sewn anastomosis may differ between the procedures. Murata et al. recently reported a retrospective study that demonstrated the superiority of stapled side-to-side gastrojejunostomy over conventional hand-sewn end-to-side gastrojejunostomy for DGE after SSPPD . Avoidance of anastomotic edema and subsequent stricture formation was considered as a possible mechanism that reduces DGE after stapled anastomosis in this study. Because there have only been a few retrospective studies to date, the efficacy of stapling anastomosis in preventing DGE after SSPPD should be studied further in larger RCTs.
POPF has been linked to DGE in the literature [26, 27]. In the present study, however, POPF was not found to be associated with DGE. Furthermore, intra-abdominal abscess, drain fluid amylase on POD three and serum C-reactive protein on POD seven were not associated with the incidence of DGE, implying that intra-abdominal inflammation played little role in the development of DGE in our cohort. It is possible that differences in patients’ backgrounds played a role. However, we were unable to identify any mechanism that could adequately explain this disparity.
There were several limitations to this study. First, it was a non-randomized study using a pre-built database. Because of the nature of the study design, there could have been patient heterogeneity. However, because this was a sub-study of a larger multicenter RCT, the database used in the present study might have been reliable. Second, the POPF definition and grading were based on the ISGPF 2005 criteria, which were revised in 2010. However, because the definition of clinically relevant POPF was only slightly altered, the changes in the new criteria may not have had an effect on the results of this study. Finally, because of the retrospective nature of the present study, there were no criteria for selecting gastrojejunostomy methods (hand-sewn or stapled). Because each surgeon selected his or her own procedures, there may be biases in analyzing risk factors for DGE.