The measurement of amylase in drain fluid for the detection of pancreatic fistula after gastric cancer surgery: an interim analysis

Surgical Outcomes of Pancreatic Solid Pseudopapillary Neoplasm: Experiences of 24 Patients in a Single Institute

Background and Objectives: The pancreatic solid pseudopapillary neoplasm (SPN), a rare tumor predominantly affecting young women, has seen an increased incidence due to improved imaging and epidemiological knowledge. This study aimed to understand the outcomes of different interventions, possible complications, and associated risk factors. Materials and Methods: This study retrospectively analyzed 24 patients who underwent pancreatic surgery for SPNs between September 1998 and July 2020. Results: Surgical intervention, typically required for symptomatic cases or pathological confirmation, yielded favorable outcomes with a 5-year survival rate of up to 97%. Despite challenges in standardizing preoperative evaluation and follow-up protocols, aggressive complete resection showed promising long-term survival and good oncological outcomes. Notably, no significant differences were found between conventional and minimally invasive (MI) surgery in perioperative outcomes. Histopathological correlations were lacking in prognosis and locations. Among the patients, one developed diffuse liver metastases 41 months postoperatively but responded well to chemotherapy and transcatheter arterial chemoembolization, with disease stability observed at 159 postoperative months. Another patient developed nonalcoholic steatohepatitis after surgery and underwent liver transplantation, succumbing to poor medication adherence 115 months after surgery. Conclusions: These findings underscore the importance of surgical intervention in managing SPNs and suggest the MI approach as a viable option with comparable outcomes to conventional surgery.

Tandem Mass Tag-Based Proteomic Profiling Identifies Biomarkers in Drainage Fluid for Early Detection of Anastomotic Leakage after Rectal Cancer Resection

Anastomotic leakage (AL), one of the most severe complications in rectal surgery, is often diagnosed late because of the low specificity of the clinical symptoms and limitations of current clinical investigations. Identification of patients with early AL remains challenging. Here, we explored the protein expression profiles of AL patients to provide potential biomarkers to identify AL in patients who undergo surgery for rectal cancer. We screened differentially expressed proteins (DEPs) in drainage fluid from AL and non-AL patients using a tandem mass tag method. A total of 248 DEPs, including 98 upregulated and 150 downregulated proteins, were identified between AL and non-AL groups. Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses suggested that DEPs were enriched in neutrophil degranulation, bacterial infection, proteolysis, hemostasis, and complement and coagulation cascades. The results of enzyme-linked immunosorbent assay validated that the expression of the top three upregulated DEPs, AMY2A, RETN, and CELA3A, was significantly increased in the drainage fluid of AL patients, compared with that of non-AL patients (AMY2A, P = 0.001; RETN, P < 0.0001; and CELA3A, P = 0.023). Thus, our findings provide several potential biomarkers for the early diagnosis of AL after rectal cancer resection.

Pancreatic thickness as a predictor of postoperative pancreatic fistula after laparoscopic or robotic gastrectomy

BACKGROUND

Despite technical advances in minimally invasive gastrectomy for gastric cancer, an increased incidence of postoperative pancreatic fistula (POPF) has been reported. POPF can cause infectious and bleeding complications, which could lead to surgery-related death; therefore, reduction of the post-gastrectomy POPF risk is crucial. This study aimed to investigate the importance of pancreatic anatomy as a predictor of POPF in patients undergoing laparoscopic or robotic gastrectomy.

METHODS

Data were collected from 331 consecutive patients who underwent laparoscopic or robotic gastrectomy for gastric cancer. The thickness of the pancreas anterior to the most ventral level of the splenic artery (TPS) was measured. The correlation between TPS and POPF incidence was investigated using univariate and multivariate analyses.

RESULTS

The cutoff value of TPS was 11.8 mm, which predicted a high drain amylase concentration on postoperative day 1, and patients were categorized into thin (Tn group) and thick TPS groups (Tk group). There was no significant difference in the background characteristics between the two groups, except for sex (P = 0.009) and body mass index (P < 0.001). The incidences of POPF grade B or higher (2% vs. 16%, P < 0.001), all postoperative complications of grade II or higher (12% vs. 28%, P = 0.004), and postoperative intra-abdominal infections of grade II or higher (4% vs. 17%, P = 0.001) were significantly higher in the Tk group. Multivariable analysis identified that high TPS was the only independent risk factor for grade B or higher POPF and grade II or higher postoperative intra-abdominal infectious complications.

CONCLUSIONS

The TPS is a specific predictive factor for POPF and postoperative intra-abdominal infectious complications in patients undergoing laparoscopic or robotic gastrectomy. Careful pancreatic manipulation during suprapancreatic lymphadenectomy is necessary for patients with increased TPS (> 11.8 mm) to avoid postoperative complications.

Somatostatin-analog effect on pancreatic fistula after radical gastrectomy: a pilot randomized controlled trial

PURPOSE

Radical gastrectomy with D2 lymphadenectomy can trigger a high incidence of postoperative pancreatic fistula (POPF), which produces a poor clinical prognosis. We sought to evaluate the effect of somatostatin analogs (SSA) on POPF and clinical prognosis after radical gastrectomy.

METHODS

A total of 123 patients with a high risk of POPF after radical gastrectomy (drainage fluid amylase concentration on a postoperative day [POD] 1 > 3 times the upper limit of normal serum amylase value) were randomly divided into the SSA group (n = 61) and the control group (n = 62). The former received continuous intravenous SSA (0.3 mg/8 h) for 3 days from POD1, and the latter normal saline. The primary outcome was the incidence of POPF.

RESULTS

The incidence of POPFs in the SSA group was significantly lower than that in the control group (3.3% vs. 14.5%, P = 0.029). The incidence of short-term postoperative complications was significantly lower in the SSA group than in the control group (9.8% vs. 24.2%, P = 0.034). The median white blood cell counts, neutrophil counts, and the percentage of neutrophils on POD4 were significantly lower in the SSA group than in the control group (all P < 0.05). The SSA group had a shorter mean time to the first liquid diet (87.33 ± 17.92 h vs. 93.97 ± 17.29 h, P = 0.039). And the SSA group had less median daily drainage volume (96.33 mL vs. 119.67 mL, P = 0.025) and shorter drainage duration (7.0 days vs. 10.0 days, P = 0.013).

CONCLUSION

Postoperative treatment with a somatostatin analog reduced the incidence of POPF and short-term complications after radical gastrectomy. (TRN: ChiCTR2200056201, Reg. Date: 2022/2/1).

Prophylactic Drain Versus No Drain in Curative Gastric Cancer Surgery-A Randomized Controlled Trial

BACKGROUND

The adoption of enhanced recovery after surgery protocols has questioned the placement of prophylactic drain after curative gastrectomy. A 2015 Cochrane meta-analysis did not find convincing evidence of routine drain placement in gastrectomy, but the quality of evidence was questioned. The present study compared short-term outcomes of prophylactic drain placement versus no drain in gastrectomy.

METHODOLOGY

The study is a prospective, non-inferiority, and randomized controlled trial. Histologically proven adenocarcinoma of the stomach undergoing curative gastrectomy with D2 lymphadenectomy was included in the study. Randomization was done intra-operatively. The primary outcome was a postoperative hospital stay. Secondary outcomes included the return of bowel function, achieving adequate enteral feeding, re-surgery, morbidity, and mortality.

RESULTS

One hundred fifty-seven patients were registered, of which 108 patients underwent curative surgery, and were randomized to 54 patients in each group. The median age was 55 years (range: 23-78) and 58.5 years (range: 35-80) in the drain and no drain group. No significant difference was noticed in primary or secondary outcomes in both groups.

CONCLUSION

Avoid placing a prophylactic drain is not inferior to drain placement following gastrectomy with D2 lymphadenectomy for stomach adenocarcinoma. So, routine prophylactic drain placement can be avoided.

Pancreatic Fistula and Biochemical Leak after Splenectomy: Incidence and Risk Factors-A Retrospective Single-Center Analysis

Purpose

Postoperative pancreatic fistula (POPF) is a complication discussed in the context of pancreatic surgery, but may also result from splenectomy; a relationship that has not been investigated extensively yet.

Methods

This retrospective single-center study aimed to analyze incidence of and risk factors for POPF after splenectomy. Patient characteristics included demographic data, surgical procedure, and intra- and postoperative complications. POPF was defined according to the International Study Group on Pancreatic Surgery as POPF of grade B and C or biochemical leak (BL).

Results

Over ten years, 247 patients were identified, of whom 163 underwent primary (spleen-associated pathologies) and 84 secondary (extrasplenic oncological or technical reasons) splenectomy. Thirty-six patients (14.6%) developed POPF of grade B/C or BL, of which 13 occurred after primary (7.9%) and 23 after secondary splenectomy (27.3%). Of these, 25 (69.4%) were BL, 7 (19.4%) POPF of grade B and 4 (11.1%) POPF of grade C. BL were treated conservatively while three patients with POPF of grade B required interventional procedures and 4 with POPF of grade C required surgery. POPF and BL was noted significantly more often after secondary splenectomy and longer procedures. Multivariate analysis confirmed secondary splenectomy and use of energy-based devices as independent risk factors for development of POPF/BL after splenectomy.

Conclusion

With an incidence of 4.5%, POPF is a relevant complication after splenectomy. The main risk factor identified was secondary splenectomy. Although POPF and BL can usually be treated conservatively, it should be emphasized when obtaining patients’ informed consent and treated at centers with experience in pancreatic surgery.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00423-022-02531-7.

Drain Amylase Concentrations at 3 h After Gastrectomy Enhance Early Prediction of Postoperative Peripancreatic Inflammatory Fluid Collection

BACKGROUND

Despite numerous studies of peripancreatic inflammatory fluid collection (PIFC) that report on the relevance of the drain amylase concentration (D-AMY), early prediction using this assay is problematic. This study aimed to investigate the clinical significance of measuring the D-AMY at 3 h after gastrectomy (POD0) for gastric cancer.

METHODS

This retrospective analysis included consecutive patients who underwent gastrectomy combined with peripancreatic lymph node dissection. The predictive value of D-AMY on POD0 and postoperative day 1 (POD1) for clinically relevant PIFC was evaluated together or individually.

RESULTS

Analyses were performed in 204 patients. Twenty (9.8%) patients experienced PIFC. D-AMY cutoffs of 721 IU/L on POD0 and 1695 IU/L on POD1 were determined using the receiver operating characteristic curve analysis for predicting PIFC. The D-AMY on POD0 had higher sensitivity (80%) but lower specificity (66.3%) for prediction of PIFC, compared with those of D-AMY on POD1 (65%, 89.1%, respectively). When combination marker analysis was performed, the highest risk group (D-AMY ≥ the cutoff values of POD0 and POD1) were associated with an elevated rate of occurrence (44%) and a high positive likelihood ratio (7.36) compared with those of the single cutoff group. The lowest risk group (D-AMY < the cutoff values on POD0 and POD1) was associated with a low rate of occurrence (2.5%) and low negative likelihood ratio (0.24) compared with those of the single cutoff group.

CONCLUSIONS

Combined measurements of D-AMYs on POD0 and POD1 enhanced early prediction of PIFC after gastrectomy.

The impact of pancreas compression time during minimally invasive gastrectomy on the postoperative complications in gastric cancer

AIM

Pancreas compression during minimally invasive gastrectomy causes blunt injury to the pancreas and leads to postoperative complications. However, the extent of practical compression associated with the incidence of postoperative complications remains unknown. This study aimed to evaluate the impact of pancreas compression, particularly the duration of compression, on short-term outcomes in minimally invasive gastrectomy for gastric cancer.

METHODS

This study included 178 patients who underwent laparoscopic or robotic gastrectomy at the Shizuoka Cancer Center in 2018. The total time of pancreas compression during gastrectomy was measured using video-reviews, and the correlation between the time and surgical outcomes was evaluated.

RESULTS

A duration of 3 min was selected as the cutoff value of pancreas compression time to predict high drain amylase concentration on postoperative day 1 (≥1000 U/L). The incidence of clinically relevant pancreatic fistula (1.5% vs 12.4%, P = .011) and all postoperative complications (12.3% vs 30.1%, P = .010) were significantly higher in the longer-compression group than in the shorter-compression group. The multivariable analysis identified longer compression as the only independent risk factor for postoperative complications.

CONCLUSION

More than a few minutes of pancreas compression during minimally invasive gastrectomy was associated with a higher incidence of postoperative complications.

Predictive value of abdominal drain amylase for postoperative pancreatic fistula following gastric resection: A systematic review and meta-analysis

BACKGROUND

Radical dissection of lymph nodes, accompanying gastric cancer resection, can lead to collateral damage to the pancreas and development of postoperative pancreatic fistula (POPF).

METHODS

We searched the Cochrane Library, MEDLINE, Embase, and Web of Science up to April 21, 2020, to identify studies documenting the value of abdominal drain amylase level (d-AMY) on postoperative day 1 (POD1) as a predictor of POPF after gastric surgery. The quality of selected studies was assessed using the QUADAS-2 tool. The diagnostic value of d-AMY on POD1 for prediction of POPF was first assessed by calculation of pooled estimates of sensitivity, specificity, likelihood ratios (LR), and the diagnostic odds ratio (DOR). Secondly, the accuracy was further demonstrated graphically with the hierarchical summary receiver operating curve (hSROC). PROSPERO registration number: CRD42020181145.

RESULTS

DOR of nine studies (cases n = 1856) observing the occurrence of POPF after measurement of d-AMY on POD1 was 18.7 (95%CI: 10.0, 34.8), and the area under hSROC was 0.88 ± 0.02. The pooled sensitivity was 0.74 (95%CI: 0.66, 0.81) and specificity 0.84 (95%CI: 0.82, 0.86). The negative LR was at the lowest point of 0.16 (95%CI: 0.07, 0.37) at the cutoff value for d-AMY of 941 IU/L, while the positive LR ranged from 4.4 (cutoff 2119 IU/L) to 6.2 (cutoff 5000 IU/L).

CONCLUSION

d-AMY on POD1 can be used as an accurate and non-invasive predictor of POPF in the earliest stage of postoperative course following gastric cancer resection; value ≤ 941 IU/L warrants early drain removal and low probability of POPF (any grade).

Amylase quantification in the terminal Ileum following formation of an Ileostomy

Amylase is elevated in the foregut and has been used to confirm anastomotic integrity after pancreatic surgery. The physiological activity of pancreatic enzymes in the ileum has been studied in healthy volunteers but not quantitated with the simple and readily available amylase measurements employed with serum tests. We aim to quantitate the levels of amylase in the terminal ileum. This was a prospective, non-randomised, non-blinded, consecutive cohort study conducted at the Royal Brisbane and Women's Hospital. Consecutive patients undergoing routine surgery with an ileostomy were invited to participate in the study. Ileostomy effluent was collected and analysed daily for the first 5 post-operative days. This validation cohort included 8 males and 3 females, with a mean age of 49 years. Median daily amylase levels ranged from 4470 U/L to 23,000 U/L, with no specimens falling within the laboratory serum reference range of 40 to 130 U/L. Two specimens were not available on day one post-operative due to complete ileus. The sample size of 11 patients is small but was considered sufficient given that 55 effluent specimens were anticipated for analysis. Amylase levels remain highly elevated as the enzyme transits through the length of the small intestine and measured in the terminal ileum, and can be readily quantitated by the existing testing methodology routinely available.

Comparison of prognostic impact of anatomic location of the pancreas on postoperative pancreatic fistula in laparoscopic and open gastrectomy

Background

Postoperative pancreatic fistula (POPF) is a serious complication after gastric cancer surgery. The current study aimed to investigate the significance of the anatomic location of the pancreas as a predictor for POPF in both laparoscopic gastrectomy (LG) and open gastrectomy (OG).

Methods

In total, 233 patients with gastric cancer were assessed retrospectively. We measured the maximum vertical (P-L height; PLH) and horizontal length (P-L depth; PLD) between the upper border of pancreas and the root of left gastric artery on a preoperative CT in the sagittal direction. The maximum length of the vertical line between the surface of the pancreas and the aorta (P-A length), previously reported as prognostic factor of POPF, was also measured. We investigated the correlations between these parameters and the incidence of POPF in LG and OG groups.

Results

Among the patients in this study, 118 underwent OG and 115 underwent LG. In LG, the median PLH and P-A length in patients with POPF were significantly longer compared with those without POPF (p = 0.026, 0.034, respectively), but not in OG. There was no significant difference in the median PLD between the patients with or without POPF in both LG and OG. The multivariate analysis demonstrated that PLH (odds ratio [OR] 4.19, 95% confidence interval [CI] 1.57–11.3, P = 0.004) and P-A length (OR 4.06, 95%CI 1.05–15.7, P = 0.042] were independent factors for predicting POPF in LG. However, intraoperative blood loss (OR 2.55, 95%CI 1.05–6.18, P = 0.038) was extracted as an independent factor in OG. The median amylase level in the drained fluid (D-Amy) were significantly higher in patients with high PLH(≥12.4 mm) or high P-A length (≥45 mm) compared with those with low PLH or low P-A length in LG. However, there were no differences in the D-Amy levels by PLH or P-A length in OG patients.

Conclusions

The anatomic location of the pancreas is a specific and independent predictor of POPF in LG but not in OG. PLH is a simple parameter that can evaluate the anatomic position of the pancreas, and it may be useful for preventing POPF after LG.

Should we still use prophylactic drain in gastrectomy for cancer? A systematic review and meta-analysis

Prophylactic drain in gastrectomy for cancer is still widely used, although some evidence has disputed this practice and spreading enhanced recovery protocol has been pushing towards surgical simplification. This study aimed at assessing the impact of drain placement on important clinical outcomes, evaluating the results of randomised controlled trials (RCTs), or cohort studies whenever information provided by the former was scarce. PubMed, PMC, Cochrane Library, CNKI and Wanfang databases were searched from January 1990 to February 2019, both for RCTs and cohort studies comparing use or avoidance of prophylactic drain in gastric cancer patients undergoing gastrectomy. All RCTs and cohort studies were rated according to Jadad score and Newcastle-Ottawa-Scale, respectively. Meta-analysis was separately performed on RCTs and cohort studies. The following clinical outcomes were considered: anastomotic leak, reoperation rate, additional drain procedure, length of stay, postoperative morbidity, postoperative mortality, readmission rate and drain related complications. Overall, 3 RCTs (330 patients) and 7 cohort studies (2897 patients) were included. Seven studies came from Eastern Countries. Meta-analysis on RCTs evidenced that drain avoidance halves overall morbidity (RR = 0.47, 95%CI 0.26-0.86, p = 0.014) and slightly reduces length of stay (SMD -0.24, 95%CI -0.51-0.03, p = 0.083). Only one postoperative death occurred in the drain group. The other outcomes were either not reported or reported just by one RCT each. Meta-analysis on cohort studies, despite higher statistical power, did not highlight any significant difference. This meta-analysis showed that prophylactic drain avoidance can reduce morbidity and length of stay, while not significantly affecting other major surgical outcomes.

Is the measurement of drain amylase content useful for predicting pancreas-related complications after gastrectomy with systematic lymphadenectomy?

Many studies investigating postoperative pancreatic fistula (POPF) after gastrectomy, including studies measuring drain amylase content (D-AMY) as a predictive factor have been reported. This article reviews previous studies and looks to the future of measuring D-AMY in patients after gastrectomy. The causes of pancreatic fluid leakage are; the parenchymal and/or thermal injury to the pancreas, and blunt injury to the pancreas by compression and retraction. Measurement of D-AMY to predict POPF has become common in clinical practice after pancreatic surgery and was later extended to the gastric surgery. Several studies have reported associations between D-AMY and POPF after gastrectomy, and the high value of D-AMY on postoperative day (POD) 1 was an independent risk factor. To improve both sensitivity and specificity, attempts have been made to enhance the predictive accuracy of factors on POD 1 as well as on POD 3 as combined markers. Although several studies have shown a high predictive ability of POPF, it has not necessarily been exploited in clinical practice. Many problems remain unresolved; ideal timing for measurement, optimal cut-off value, and means of intervention after prediction. Prospective clinical trial could be imperative in order to develop D-AMY measurement in common clinical practice for gastric surgery.

Intraoperative Body Fluid Amylase as a Novel Indicator of Postgastrectomy Pancreatic Fistula

BACKGROUND

Although many methods to prevent the development of postoperative pancreatic fistula (POPF) after gastrectomy have been reported, POPF can only be identified after it has occurred. Various therapeutic measures could be taken if signs of POPF could be detected intraoperatively.

METHODS

We conducted a prospective study in which we attempted to predict POPF by measuring the intraoperative amylase concentration in the peripancreatic body fluid. To collect the body fluid, three sponges were placed around the pancreas at lymph node station Nos. 6, 8, and 11 during lymphadenectomy. The amylase concentration was measured in the body fluid squeezed from the sponges. We investigated whether the intraoperative body fluid amylase concentration (IBAC) was associated with POPF formation.

RESULTS

In total, 109 patients were enrolled from February 2016 to March 2018, and we analyzed 81 eligible patients. Clavien-Dindo grade ≥ II POPF occurred in eight patients (9%). The IBAC was significantly higher in sponges No. 6 (P = 0.044) and No. 8 (P = 0.007). The incidence of POPF was predicted by using an IBAC cutoff value for No. 6 (1047 IU/L; sensitivity 87.5%; specificity 65.0%; positive likelihood ratio 2.5) and No. 8 (400 IU/L; sensitivity 87.5%; specificity 68.5%; positive likelihood value 2.8), respectively. The IBAC in sponge No. 11 tended to be higher (P = 0.054).

CONCLUSIONS

By measuring the IBAC, surgeons might predict POPF easily and noninvasively during surgery. This method is one of the most effective ways to predict POPF intraoperatively.

Impact of high amylase level in drainage fluid after gastric cancer surgery: Is it a complication or suspicious biochemical measurement?

Purpose: Pancreatic fistula is a potential postoperative complication with variable definitions, incidences and risk factors. We intended to evaluate its impact after gastric surgery. Materials and Methods: A total of 28 consecutive patients who underwent curative open gastrectomy with lymphadenectomy for gastric adenocarcinoma were retrospectively analyzed. Patients’ demographics, peri-operative and pathological data were collected. Pancreatic fistula that was diagnosed and graded according to International Study Group of Pancreatic Fistula’s system was identified as main variable.Results: Mean age of patients was 58.8±10.1 years with a female to male ratio of 9/19. Grade A pancreatic fistula was diagnosed in six patients (21.4%). There was no grade B and C pancreatic fistula. Drain amylase level was significantly higher in patients with pancreatic fistula (p=0.0001). There was no significant difference with regard to amount of drainage, length of hospital stay and duration of drains in patients with and without fistula. No significant association was shown between development of fistula and patients’ demographics, peri-operative and pathological data. Conclusion: The development of grade A pancreatic fistula after gastric surgery does not appear to be a major complication with clinical consequences. High amylase level in the drainage fluid can be considered as a biochemical measure only.  

Two-point measurement of amylase in drainage fluid predicts severe postoperative pancreatic fistula after gastric cancer surgery

BACKGROUND

Early identification of patients at risk of postoperative pancreatic fistula (POPF) allows appropriate management after gastrectomy. Although some reports have suggested a correlation between POPF and the concentration of amylase in drained abdominal fluid (D-AMY), this has not been proven to impact sufficiently on clinical decision-making. A sustained high level of D-AMY is often assumed to be due to unsatisfactory drainage or excessive pancreatic leakage. We assessed the clinical utility of measuring D-AMY on postoperative day (POD) 1 and POD3 for prediction of POPF.

METHODS

Starting in April 2014, 801 patients who underwent radical gastrectomy with prophylactic drain placement were consecutively enrolled. We routinely measured D-AMY on POD1 and POD3, and compared the incidence of problematic POPF and clinical factors including D-AMY. We also attempted to clarify whether such two-point D-AMY measurement was clinically useful for patient management after gastrectomy.

RESULTS

Fifty-one of the patients (6.4%) developed Clavien-Dindo grade III or worse POPF. Using D-AMY cutoffs of 2218 IU/L on POD1 and 555 IU/L on POD3, the patients were successfully classified. The highest risk group, in which D-AMY was higher than the cut-off value on both POD1 and POD3, showed a significantly high rate of occurrence (33/105, 31.4%) and high positive likelihood ratio (6.74). Multivariate analysis showed that classification into this highest risk group was an independent risk factor for development of severe POPF (odds ratio 15.2, 95% CI 7.92-29.0).

CONCLUSION

Two-point measurement of D-AMY may be an efficient tool for achieving individualized management of POPF following radical gastrectomy.

Impact of anatomical position of the pancreas on postoperative complications and drain amylase concentrations after laparoscopic distal gastrectomy for gastric cancer

BACKGROUND

Laparoscopic surgery for gastric cancer requires traction or compression of the pancreas, with the extent depending on the anatomical position of the pancreas. This study investigated the impact of the position of the pancreas on postoperative complications and drain amylase concentrations after laparoscopic distal gastrectomy (LDG).

METHODS

Gastric cancer patients who underwent LDG were assessed retrospectively. The following anatomical parameters were measured retrospectively in preoperative computed tomography sagittal projections: the length of the vertical line between the pancreas and the aorta (P-A length), representing the height of the slope looking down the celiac artery from the top of the pancreas, and the angle between a line drawn from the upper border of the pancreas to the root of the celiac artery and the aorta (UP-CA angle), representing the steepness of the slope. Correlations between each parameter and postoperative complications were analyzed by logistic regression analysis. Pearson's product-moment correlation coefficients were calculated for scatter diagrams for each parameter and drain amylase concentration on postoperative day 1.

RESULTS

Analyses were performed in 394 patients. P-A length [odds ratio (OR) 1.905; 95% confidence interval (CI) 1.100-3.300; P = 0.021] was significantly correlated with pancreatic fistula. P-A length (OR 2.771; 95% CI 1.506-5.098; P = 0.001), UP-CA angle (OR 2.323; 95% CI 1.251-4.314; P = 0.008), and low preoperative serum albumin (OR 2.082; 95% CI 1.050-4.128; P = 0.036) were significantly correlated with overall postoperative complications defined as Clavien-Dindo ≥ grade II. P-A length and UP-CA angle showed significant positive correlations with drain amylase concentration on postoperative day 1.

CONCLUSION

The position of the pancreas is an independent predictor of pancreatic fistula and/or postoperative complications and correlates with drain amylase concentration after LDG for gastric cancer.

Detection of digestive malignancies and post-gastrectomy complications via gastrointestinal fluid examination

To date, gastric carcinoma (GC) is one of the common and fatal digestive malignancies worldwide. The prognosis of GC is not always satisfactory because of late diagnosis. Scholars are keen on discovering novel accurate and economical biomarkers in body liquids for GC screening to detect and evaluate the lesion before the results of imaging techniques are obtained. While traditional serum assays have limited sensitivity and specificity, gastrointestinal juice may provide relevant specific biomarkers because of its close contact with the tumor. Herein, the current progress in the relationship between gastrointestinal fluid analyses and GC is systematically and comprehensively reviewed. The detection of gastric juice pH, fluorescence spectrum, cytology, Helicobacter pylori-associated markers, nitrosamines, conventional tumor markers, amino acids, proteomics, microRNAs, long noncoding RNAs, protein-coding genes, vitamin C, etc., and combination tests of different category markers could provide important diagnostic and prognostic clues for gastrointestinal diseases. Particularly, early GC may be efficiently screened using gastric juice. Gastrointestinal fluid examination could also predict the adverse effects of postgastrectomy, such as pancreatic leakage, fistula, and abscess. Gastric fluid markers should be further studied to reveal the early predicators of malignancy and complications. The methods for obtaining the samples of gastrointestinal juice with minimum incision should also be comprehensively investigated.

Förster Resonance Energy Transfer-Based Self-Assembled Nanoprobe for Rapid and Sensitive Detection of Postoperative Pancreatic Fistula

Postoperative pancreatic fistula (POPF) is the most serious and challenging complication following gastroenterological surgery. Activated pancreatic juice leaking from the organ remnant contains proteases that attack the surrounding tissue, potentially leading to severe inflammation, tissue necrosis, and fistula formation. However, it is difficult to observe pancreatic leakage during surgery and to evaluate the protease activity of leaked fluid at the patient's bedside. This report describes a protein nanocage-based protease ratiometric sensor comprising a pancreatic protease-sensitive small heat-shock protein (HSP) 16.5, which is a naturally occurring protein in Methanococcus jannaschii that forms a spherical structure by self-assembly of 24 subunits, and a chemically conjugated donor-acceptor dye pair for Förster resonance energy transfer (FRET). The HSP-FRET probe was constructed by subunit exchange of each dye-labeled engineered HSP, resulting in a spherical nanocage of approximately 10 nm in diameter, which exhibited very high stability against degradation in blood plasma and no remarkable toxicity in mice. The efficiency of FRET was found to depend on both the dye orientation and the acceptor/donor ratio. Pancreatic proteases, including trypsin, α-chymotrypsin, and elastase, were quantitatively analyzed by fluorescence recovery with high specificity using the HSP-FRET nanoprobe. Furthermore, the HSP-FRET nanoprobe was sufficiently sensitive to detect POPF in the pancreatic juice of patients using only the naked eye within 10 min. Thus, this novel nanoprobe is proposed as an effective and convenient tool for the detection of POPF and the visualization of activated pancreatic juice during gastroenterological surgery.