UNASSIGNED: Despite the remarkable progress in minimally invasive surgery, the potential association between laparoscopic gastrectomy and the risk of peritoneal metastasis remains uncertain.
UNASSIGNED: To investigate variations in tumour markers in intraperitoneal drainage fluid between laparoscopic radical gastrectomy and open radical gastrectomy for gastric cancer.
UNASSIGNED: A total of 106 patients diagnosed with gastric cancer between July 2018 and November 2020 were included in this study, 45 of whom underwent laparoscopic radical gastrectomy (laparoscopic group) and 61 underwent open radical gastrectomy (open group). Variations in the levels of carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), cancer antigen 199 (CA199), and α-fetoprotein (AFP) in the intraperitoneal drainage fluid were compared and analysed on postoperative days (PODs) 1, 2, 3, and 5 between the two groups. Additionally, the postoperative 3-year survival rates between the two groups were compared and analysed.
UNASSIGNED: No significant differences in CEA, CA199, and AFP levels in the intraperitoneal drainage fluid were observed between the two groups on postoperative days (PODs) 1, 2, 3, and 5 (p > 0.05). However, the level of CA125 in the intraperitoneal drainage fluid of the laparoscopic group was notably higher than that of the open group on POD 2 (p < 0.05); however, there were no significant differences between the two groups on PODs 1, 3, and 5 (p > 0.05). There was no significant difference in the 3-year postoperative survival rates between the two groups.
UNASSIGNED: There were no significant differences in CEA, CA125, CA199, and AFP levels in the intraperitoneal drainage fluid between laparoscopic radical gastrectomy and open radical gastrectomy for gastric cancer, confirming from another perspective that laparoscopic radical gastrectomy does not increase the risk of intraperitoneal metastasis.

UNASSIGNED: Prolonged wound drainage (PWD) is one of the most important reasons that increase the risk of early periprosthetic joint infection after arthroplasty. It is very important to evaluate the risk factors for PWD in the surgical field after arthroplasty surgery. This can be accomplished using machine learning or artificial intelligence methods. Our aim in this study was to compare machine learning methods in predicting possible PWD.
UNASSIGNED: The study was carried out on clinical, laboratory, and radiological data of 313 patients who underwent hemiarthroplasty (HA) for proximal femur fractures. We preprocessed the dataset and trained and tested machine learning methods using cross validation. We compared various machine learning algorithms (linear discriminant analysis, decision tree, k-nearest neighbors, gradient boosting machine, and logistic regression [LR]) based on performance measures. We also combined the most successful algorithms with a metaclassifier. To help understand the relationship between risk factors, we provided a risk factor severity ranking.
UNASSIGNED: To estimate the risk of PWD, classification was performed with first-level classifiers and then integrated as a LR-based meta-learner stacking method. More performance improvements were achieved with the stacking method.
UNASSIGNED: We found that the stacking method was superior to other methods in PWD classification. We determined that the volume of fluid collected from the drain, morbid obesity class, blood transfusion, and body mass index score were the four most important risk factors according to stacking.

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.

UNASSIGNED: Early detection of surgical site infection (SSI) allows for appropriate management after Crohn\'s disease (CD) surgery. The aim of this study was to evaluate the usefulness of bacterial culture of postoperative drainage fluid after CD surgery.
UNASSIGNED: This study included 110 patients with CD who underwent surgery with bowel resection between January 2010 and March 2020 at Osaka University Hospital. Patients with only perianal surgery or incomplete records were excluded. Risk factors for SSI were evaluated in the context of clinical findings, including bacterial culture of postoperative drainage fluid, and bacterial species related to SSI were also examined.
UNASSIGNED: Of 110 patients, 18 (16.4%) developed SSI. Organ/space SSI developed in six, and a positive bacterial culture of drainage fluid (D-Posi) was found in five (83.3%). Of 104 patients without organ/space SSI, 31 (29.8%) were D-Posi (P = .027). Similarly, 68.8% with incisional SSI were D-Posi, whereas 26.6% without incisional SSI were D-Posi (P = .0021). Multivariate analysis revealed that D-Posi was an independent risk factor in both organ/space and incisional SSI. Bacterial examination showed that Pseudomonas aeruginosa and Enterococcus faecalis were significantly detected in patients with SSI.
UNASSIGNED: This study suggests the usefulness of postoperative drainage fluid bacterial culture for early diagnosis of SSI after CD surgery.

BACKGROUND: The drain amylase concentration (dAmy-C) is a useful marker for predicting pancreatic fistula after gastric cancer surgery. However, dAmy-C might be reduced in cases of high drainage volume. Therefore, we hypothesized that we could accurately assess the amount of amylase leaked from the pancreas by multiplying dAmy-C by the daily drainage volume. In this study, we investigated the clinical utility of the amount of drain amylase (A-dAmy: concentration × volume) for predicting pancreatic fistula. We investigated the clinical utility of the combination of dAmy-C and A-dAmy for predicting pancreatic fistula.
METHODS: We investigated patients who underwent gastrectomy for gastric cancer at Yodogawa Christian Hospital between 2012 and 2020. The optimal cutoff levels of dAmy-C and A-dAmy on postoperative day 1 for predicting Clavien-Dindo (CD) grade II or higher pancreatic fistula was calculated using receiver operating characteristic (ROC) curves. We calculate the positive predictive value and negative predictive value for predicting pancreatic fistula using these cutoff levels.
RESULTS: A total of 448 patients were eligible for analysis. Twenty-two patients experienced CD grade II or higher pancreatic fistula. ROC curves identified 1,615 IU/L as the optimal cutoff level of dAmy-C, predicting pancreatic fistula. When the simple cutoff level of dAmy-C was 1,600 IU/L, the positive predictive value for was 22.8%, and the negative predictive value was 99.7%. ROC curves identified 177.52 IU as the optimal cutoff level of A-dAmy predicting pancreatic fistula. When the simple cutoff level of A-dAmy was 177 IU, the positive predictive value was 21.2%, and the negative predictive value was 99.7%. Using these two cutoff levels together, the positive predictive value was 34.4%, and the negative predictive value was 99.7%.
CONCLUSIONS: A-dAmy could predict and exclude pancreatic fistula after gastrectomy as with dAmy-C. The combination of dAmy-C and A-dAmy predict pancreatic fistula more accurately than dAmy-C alone.

BACKGROUND: Although the rates of surgical site infection are decreasing, surgical site infection after pancreatectomy remains frequent because of postoperative pancreatic fistula. Recent studies suggested a relationship between postoperative pancreatic fistula and pathogens cultured from drainage fluids after pancreatectomy. This study aimed to assess and evaluate high-risk pathogens cultured from postoperative drainage fluids for postoperative pancreatic fistulas or severe postoperative complications after pancreatectomy.
METHODS: We retrospectively enrolled patients who underwent pancreaticoduodenectomy or distal pancreatectomy between 2012 and 2019. We assessed clinical characteristics and microbiological results of drainage cultures of pancreaticoduodenectomy or distal pancreatectomy patients, and we investigated the risk factors for clinically relevant postoperative pancreatic fistulas and Clavien-Dindo status using univariate and multivariate analyses. Finally, we detected high-risk pathogens from drainage cultures and analyzed the correlation between these pathogens and the severity of clinically relevant postoperative pancreatic fistula or Clavien-Dindo status.
RESULTS: Four hundred and twenty-nine patients were enrolled: 257 underwent pancreaticoduodenectomy and 172 underwent distal pancreatectomy. Clinically relevant postoperative pancreatic fistulas and Clavien-Dindo status ≥ III were more frequently seen in pancreaticoduodenectomy patients than in distal pancreatectomy patients, namely grade C postoperative pancreatic fistula, which was observed in 19 pancreaticoduodenectomy patients. The most common pathogen found from drainage cultures was Enterococcus species, followed by Enterobacter species and Candida species. All pathogens were associated with clinically relevant postoperative pancreatic fistulas; however, Candida species was a dominant microorganism of clinically relevant postoperative pancreatic fistulas grade C, Clavien-Dindo status ≥ IV, and hemorrhage due to pseudoaneurysm.
CONCLUSIONS: The presence of Candida species in the drainage fluid culture after pancreaticoduodenectomy can be a predictive factor of severe infectious complications, including postoperative pancreatic fistulas; thus, we should regularly collect cultures from drainage fluids and monitor for Candida infection.

UNASSIGNED: This study aimed to clarify the effect of thoracic drainage fluid (DF) on lung cancer cells in vitro.
UNASSIGNED: We assessed the influence of DF on the proliferation and migration of lung cancer cells (LTEP-a-2 and A549) using the MTT cell proliferation assay and scratch wound assay. Cell apoptosis was determined by flow cytometric analysis. We also investigated the effect of DF on drug chemosensitivity, assessing viability of LTEP-a-2 and A549 cells.
UNASSIGNED: The proliferative rates of cancer cells in the DF-treated group were significantly higher than those of the control group. Similar results were obtained for cell migration of lung cancer cells. Cells in the DF-treated groups showed a lower percentage of apoptosis than those of the control groups. Chemosensitivity of lung cancer cells to doxycycline and cisplatin (DDP) was lowered by DF.
UNASSIGNED: These findings suggest that DF affects lung cancer cells by promoting proliferation and migration, inhibiting apoptosis, and increasing drug resistance.

OBJECTIVE: It is widely accepted that postoperative pancreatic fistula (POPF) accompanied by bacterial infection results in a worse outcome than POPF alone. However, few studies evaluating predictive indicators of POPF have focused on bacterial infection.
METHODS: A consecutive 100 patients who underwent pancreaticoduodenectomy at our institute for periampullary disease were enrolled. POPF was assessed according to the International Study Group of Pancreatic Fistula consensus guidelines; grades B and C were defined as clinically relevant POPF (CR-POPF). The patients\' characteristics, perioperative surgical factors, and laboratory data including the results of culture and smear testing performed using drainage fluid on postoperative days (PODs) 1 and 3 were analyzed.
RESULTS: The overall incidence of CR-POPF was 25%. Univariate analyses revealed that the factors associated with CR-POPF were male sex, soft pancreas, MPD diameter, higher serum C-reactive protein concentration and white blood cell count on POD 3, higher amylase concentration in drainage fluid, and culture and/or smear positivity of drainage fluid. Multivariate analysis newly revealed that the smear positivity of drainage fluid on POD 3 was the independent risk factors for CR-POPF (p = 0.027).
CONCLUSIONS: Smear positivity of drainage fluid on POD 3 after pancreaticoduodenectomy may be a new predictor of CR-POPF.

Systematic cultures of drain tips or drainage fluids for the early detection of surgical site infections (SSIs) are controversial. To examine the association between the results of systematic drain tip or drainage fluid cultures and the occurrence of SSIs in clean or clean-contaminated surgery. Searches were performed in the PubMed, and Cat.inist databases for observational studies published before 31st March 2017. Studies reporting results of drain tip or drainage fluid systematic cultures and SSIs after clean or clean-contaminated surgeries were included, and meta-analyses were performed. Seventeen studies, including 4390 patients for drain tip cultures and 1288 for drainage fluid cultures, were selected. The pooled negative predictive values were high (99%, 95% confidence interval (CI) 98-100 for drain tip cultures and 98%, 95% CI 94-100 for drainage fluid cultures). The positive predictive values were low (11%, 95% CI 2-24 for drain tip cultures and 12%, 95% CI 3-24 for drainage fluid cultures). The sensitivities were low (41%, 95% CI 12-73 for drain tip cultures and 37%, 95% CI 16-60 for drainage fluid cultures). The specificities were high (93%, 95% CI 88-96) for drain tip cultures and moderate (77%, 95% CI 54-94) for drainage fluid cultures. Systematic cultures of drain tips or drainage fluids appear not to be relevant, because their positive predictive values were low in the prediction of SSIs.

Lymphedema (LE) following lymph node dissection is a major problem for cancer patients, and radiation therapy, extended surgery, groin dissection, obesity, and older age are well-established risk factors of LE. We studied whether these risk factors are further associated with high volumes of postoperative drainage fluid after complete lymph node dissection (CLND) for melanoma metastases. Moreover, we examined whether a high amount of drainage fluid after sentinel lymph node biopsy (SLNB) can predict a high amount of drainage fluid after subsequent CLND. Using descriptive statistics and regression analyses, we analyzed the cumulative volumes of postoperative drainage fluid for 836 melanoma patients with lymph node excision in the axilla or groin. In multiple regression analyses, the well-established risk factors of LE, i.e., increased body mass index, older age, and ilioinguinal versus inguinal versus axillary dissection predicted a high drainage volume after CLND. Of note, a high drainage fluid volume after SLNB also predicted a high drainage volume after subsequent CLND. In patients with groin dissections, who are particularly susceptible to swelling, extended iliac dissection, age above 60, and a cumulative drainage volume of more than 100 ml in the preceding SLNB were predictors of the cumulative drainage volume. We find that common risk factors predict the volume of postoperative drainage fluid after CLND and postoperative LE. Further, high postoperative drainage volume may therefore function as a potential early predictor of LE following CLND.