High serum proteinase-3 levels predict poor progression-free survival and lower efficacy of bevacizumab in metastatic colorectal cancer.

BACKGROUND: To improve the prognosis of patients with metastatic colorectal cancer (mCRC), investigating predictive biomarkers of their prognosis and chemotherapeutic responsiveness is necessary. This study aimed to analyze the clinical significance of serum proteinase-3 (PRTN3) as a predictor for prognosis and chemosensitivity, especially to bevacizumab therapy, in mCRC. METHODS: This single-center retrospective observational study enrolled 79 patients with mCRC in our hospital and 353 patients with colorectal cancer in the TCGA database. Preoperative serum PRTN3 levels were measured using an enzyme-linked immunosorbent assay. The clinicopathological characteristics and prognosis according to serum PRTN3 levels were then evaluated. PRTN3 expression in tumor and stromal cells was evaluated immunohistochemically. The impact of PRTN3 levels on angiogenesis and bevacizumab sensitivity was evaluated using the tube formation assay. RESULTS: Serum PRTN3 levels were an independent poor prognostic factor for progression-free survival (PFS) (hazard ratio, 2.082; 95% confidence interval, 1.118-3.647; P=0.010) in patients with mCRC. Similarly, prognostic analysis with TCGA data sets showed poorer overall survival in patients with PRTN3 expression than that in patients without PRTN3 expression, especially in patients with stage IV. Immunohistochemical analysis of resected specimens revealed that stromal neutrophils expressed PRTN3, and their expression level was significantly correlated with serum PRTN3 levels. Interestingly, the effectiveness of first-line chemotherapy was significantly poorer in the high serum PRTN3 level group. High serum PRTN3 was significantly associated with poor PFS (hazard ratio, 3.027; 95% confidence interval, 1.175-7.793; P=0.0161) in patients treated with bevacizumab, an anti-angiogenic inhibitor. The tube formation assay revealed that PRTN3 administration notably augmented angiogenesis while simultaneously attenuating the anti-angiogenic influence exerted by bevacizumab therapy. CONCLUSIONS: Serum PRTN3 levels could be a novel predictive biomarker of PFS of first-line chemotherapy, especially for bevacizumab therapy, in patients with mCRC.

IL-6 Levels Correlate with Prognosis and Immunosuppressive Stromal Cells in Patients with Colorectal Cancer.

BACKGROUND: The prognosis for patients with colorectal cancer (CRC) is determined by tumor characteristics as well as the host immune response. This study investigated the relationship between an immunosuppressive state and patient prognosis by evaluating the systemic and tumor microenvironment (TME) interleukin (IL)-6 levels. METHODS: Preoperative serum IL-6 levels were measured using an electrochemiluminescence assay. Expression of IL-6 in tumor and stromal cells was evaluated immunohistochemically in 209 patients with resected CRC. Single-cell analysis of tumor-infiltrating immune cells was performed using mass cytometry in 10 additional cases. RESULTS: Elevated serum IL-6 levels were associated with elevated stromal IL-6 levels and a poor prognosis for patients with CRC. High IL-6 expression in stromal cells was associated with low-density subsets of CD3+ and CD4+ T cells as well as FOXP3+ cells. Mass cytometry analysis showed that IL-6+ cells among tumor-infiltrating immune cells were composed primarily of myeloid cells and rarely of lymphoid cells. In the high-IL-6-expression group, the percentages of myeloid-derived suppressor cells (MDSCs) and CD4+FOXP3highCD45RA- effector regulatory T cells (eTreg) were significantly higher than in the low-IL-6-expression group. Furthermore, the proportion of IL-10+ cells in MDSCs and that of IL-10+ or CTLA-4+ cells in eTregs correlated with IL-6 levels. CONCLUSION: Elevated serum IL-6 levels were associated with stromal IL-6 levels in CRC. High IL-6 expression in tumor-infiltrating immune cells also was associated with accumulation of immunosuppressive cells in the TME.

Phase I study of a novel therapeutic vaccine as perioperative treatment for patients with surgically resectable hepatocellular carcinoma: The YCP02 trial.

AIM: Developing effective adjuvant therapies is essential for improving the surgical outcomes in patients with hepatocellular carcinoma (HCC). Immunotherapy against HCC has become a promising strategy; however, only approximately 30% of all HCC patients respond to immunotherapy. Previously, we generated the novel therapeutic vaccine comprising multi-human leukocyte antigen-binding heat shock protein 70/glypican-3 peptides with a novel adjuvant combination of hLAG-3Ig and poly-ICLC. We also confirmed the safety of this vaccination therapy, as well as its capacity for the effective induction of immune responses in a previous clinical trial. METHODS: In this phase I study, we administered this vaccine intradermally six times before surgery, and 10 times after surgery to patients with untreated, surgically resectable HCC (stage II to IVa). The primary end-points of this study were the safety and feasibility of this treatment. We also analyzed the resected tumor specimens pathologically using hematoxylin-eosin staining and immunohistochemistry for heat shock protein 70, glypican 3, CD8 and programmed death-1. RESULTS: A total of 20 human leukocyte antigen-matched patients received this vaccination therapy with an acceptable side-effect profile. All patients underwent planned surgery without vaccination-related delay. Immunohistochemical analyses revealed that potent infiltration of CD8+ T cells into tumors with target antigen expression was observed in 12 of 20 (60%) patients. CONCLUSIONS: This novel therapeutic vaccine was safe as perioperative immunotherapy for patients with HCC, and has the potential to strongly induce CD8+ T cells infiltration into tumors.

A novel prediction model of pancreatic fistula after pancreaticoduodenectomy using only preoperative markers.

BACKGROUND: Since clinically relevant postoperative pancreatic fistula (CR-POPF) can cause intra-abdominal hemorrhage and abscesses, leading to surgery-related deaths after pancreaticoduodenectomy (PD), its preoperative prediction is important to develop strategies for surgical procedures and perioperative management. This study aimed to establish a novel prediction model for CR-POPF using preoperative markers. METHODS: On a training set of 180 patients who underwent PD at the Yamaguchi University Hospital, a combination of CR-POPF predictors were explored using the leave-one-out method with a unique discrete Bayes classifier. This predictive model was confirmed using a validation set of 366 patients who underwent PD at the Osaka University Hospital. RESULTS: In the training set, CR-POPF occurred in 60 (33%)　of 180 patients and 130 (36%)　of 366 patients in the validation set using selected markers. In patients with pancreatic ductal adenocarcinoma (PDAC), the main pancreatic duct (MPD) index showed the highest prognostic performance and could differentiate CR-POPF with 87% sensitivity and 81% specificity among 84 patients in the training set. In the validation set, the sensitivity and specificity of the MPD index-based model for 130 PDAC samples were 93% and 87%, respectively. In patients with non-PDAC, the MPD index/body mass index (BMI) combination showed the highest prognostic performance and could differentiate CR-POPF with 84% sensitivity and 57% specificity among 96 patients in the training set. In the validation set, the sensitivity and specificity of the MPD index/BMI-based model for 236 non-PDAC samples were 85% and 53%, respectively. CONCLUSION: We developed a novel prediction model for pancreatic fistulas after PD using only preoperative markers. The MPD index and MPD index/BMI combination will be useful for CR-POPF assessment in PDAC and non-PDAC samples, respectively.

[A Severe Case of Bleeding from Duodenal Invasion Due to Co-Morbid IPMC with Arcuate Ligament Syndrome and IPDA Aneurysm].

An 81-year-old man with a history of left hemiplegia due to a cerebral hemorrhage was admitted to a clinic because of tarry stools. Endoscopic findings revealed an ulcerative lesion with hemorrhage in the descending duodenum. The patient was transferred to our hospital for treatment. Because endoscopic hemostasis was impossible, interventional radiology(IVR) hemostasis was performed using coil embolization for the feeding artery. Simultaneously, angiography showed stenosis of the root of the celiac axis due to arch ligament syndrome and an aneurysm of the inferior pancreaticoduodenal artery (IPDA). Due to the risk of rebleeding, subtotal stomach-preserving pancreatoduodenectomy was performed after the patient's overall condition had stabilized. Despite dissecting the arcuate ligament, the hepatic artery flow did not improve. Hence, a direct arterial anastomosis between the middle colic artery and the gastroduodenal artery was performed. Furthermore, due to the proximity of the IPDA aneurysm to the superior mesenteric artery, IVR embolization for the IPDA aneurysm was performed on postoperative day 8, and he was transferred to a rehabilitation hospital on postoperative day 57. The pathological result was invasive intraductal papillary mucinous carcinoma(IPMC). The patient has been an outpatient with no recurrence 12 months postoperatively.

[Invasive Ductal Carcinoma within a Borderline Malignancy Phyllodes Tumor-A Case Report].

Phyllodes tumors are uncommon breast neoplasms that constitute 1-2% of breast malignancies. Invasive ductal carcinoma in the epithelial component of phyllodes tumor is very rare. When carcinoma is detected within the specimen, the management of treatment changes completely. We report a rare case of invasive ductal carcinoma arising in a giant borderline malignancy phyllodes tumor in a 51-year-old female patient. A painful 20 cm mass was found in her right breast, and a needle biopsy revealed fibroadenoma or benign phyllodes tumor, and a total mastectomy was performed. Pathological results showed that a borderline malignant phyllodes tumor coexisted with invasive ductal carcinoma. We explained that axillary surgery was necessary because invasive cancer was diagnosed after surgery, but the patient requested follow-up using images. Endocrine therapy was performed as postoperative adjuvant therapy, and the follow-up is underway without recurrence.

[A Case of Malignant Lymphoma of the Bile Duct Mimicking Cholangiocarcinoma].

During the postoperative follow-up for adrenal tumor for a 78-year-old male patient, a contrast-enhanced computed tomography scan revealed wall thickness with contrast effect in the cystic duct, enlarged lymph nodes along the ileocecal artery, and nodal shadow in the lower lobe of the left lung. First, the collected bile juice at ERC was submitted to cytology multiple times however, no malignant findings were noted. Next, a staging laparoscopy was performed; but the pathological findings of the enlarged lymph nodes and the abdominal lavage cytology showed no malignancy. A nodule in the lower lobe of the left lung was resected for diagnostic and therapeutic purposes, and the pathological diagnosis was primary adenocarcinoma of the lung. Finally the patient underwent exploratory laparotomy for diagnostic purposes. An intraoperative ultrasound- guided needle biopsy for mass lesion located in the medial section of the left liver was performed, and malignant lymphoma was suspected by the intraoperative pathological diagnosis. Cholecystectomy was performed to confirm the histological type, leading to the diagnosis of diffuse large B cell lymphoma. After surgery, the patient underwent 6 courses of rituximab plus CHOP therapy, and the bile duct stricture was improved.

Immune Evasion of Hepatoma Cancer Stem-Like Cells from Natural Killer Cells.

BACKGROUND: Poor prognosis in liver cancer is due to its high frequency of intrahepatic metastasis. Cancer stem-like cells (CSLCs), which possess the properties of stemness, tumor initiation capability, and resistance to therapy, also exhibit metastatic potential. Immune surveillance plays an important role in the accomplishment of metastasis. Herein, the property of immune evasion in CSLCs was investigated. METHODS: Sphere cells were induced as CSLCs using a sphere induction medium containing neural survival factor-1. The expression of genes involved in immune evasion was determined using RNA-sequencing for sphere and parental cells followed by validation using flow cytometric analysis and ELISA. Susceptibility to natural killer (NK) cell-mediated cytotoxicity was examined by a chromium release assay. A xenograft model using BALB/c nu/nu mice was used to assess tumor growth. Gene set enrichment analysis was performed for interpreting RNA sequencing. RESULTS: The cell surface expressions of PD-L1, PD-L2, and CEACAM1 were upregulated and those of ULBP1 and MICA/MICB were downregulated in SK-sphere, CSLCs derived from SK-HEP-1, compared with that in parental cells. Levels of soluble MICA were elevated in conditioned medium from SK-sphere. Expression of HLA class I was not downregulated in SK-sphere. The susceptibilities to NK cell-mediated killing and secreted perforin were significantly lower in both CSLCs derived from SK-HEP-1 and HLE than in parental cells. Tumors formed upon inoculation of SK-sphere in immunodeficient mice harboring NK cells were larger than those formed upon inoculation of parental cells. CONCLUSION: Human hepatoma cell line-derived CSLCs may possess immune evasion properties, especially from NK cell-mediated immunity.

CD4 and FOXP3 as predictive markers for the recurrence of T3/T4a stage II colorectal cancer: applying a novel discrete Bayes decision rule.

BACKGROUND: We recently reported the relapse-free survival (RFS) significance of the combination of CD4+ and forkhead box P3+ (FOXP3) T-cell densities identified by immunohistochemistry in patients with stage I, II, and III colorectal cancer (CRC) who underwent curative resections. This study was designed to determine the optimal combination of markers that predict recurrence in patients with T factors of T3/T4a stage II CRC by applying a novel Bayes decision rule. METHODS: Using 137 cancer tissue specimens from T3/T4a stage II patients, 12 clinicopathologic and immune factors were analysed as predictive candidates for recurrence. RESULTS: Our study showed that the combination of low CD4+ and low FOXP3+ T-cell densities resulted in extremely poor RFS. CONCLUSIONS: Adjuvant chemotherapy may be considered for patients with a combination of low CD4+ and low FOXP3+ T-cell densities. The discovery of this new prognostic indicator is important for the appropriate management of patients undergoing curative resection for T3/T4a stage II CRC.

Elevated expression of RAB3B plays important roles in chemoresistance and metastatic potential of hepatoma cells.

BACKGROUND: Cancer stem cells (CSCs) are thought to play important roles in carcinogenesis, recurrence, metastasis, and therapy-resistance. We have successfully induced cancer stem-like sphere cells (CSLCs) which possess enhanced chemoresistance and metastatic potential. To enable the development of targeted therapy against CSLCs, we identified a gene responsible for this phenotype in CSLC. METHODS: Human hepatoma cell line SK-HEP-1 was used for CSLC induction with a unique sphere inducing medium, and HuH-7 cells were used as non-sphere forming cells in the same condition. RNA-sequencing was performed followed by validation with quantitative RT-PCR and western blotting. Knockdown experiments were done by using CRISPR-Cas9 genome-editing, and the rescue experiments were performed using the expressing plasmid vector. Chemoresistance and liver metastasis of the cells, was studied following the splenic injection of cells to severely immune deficient mice and evaluated using the MTS assay. Quantification of exosomes in the medium was done using ELISA. RESULTS: RAB3B was identified as an up-regulated gene in both CSLCs and prognostically poor hepatocellular carcinoma (HCC) by RNA-sequencing. RAB3B-KD cells showed altered CSLC phenotypes such as sphere formation, chemoresistance, and metastatic potentials, and those were rescued by RAB3B complementation. Increased exosome secretion was observed in CSLCs, and it was not observed in the RAB3B-KD cells. In addition, the RAB3B expression correlated with the expression of ABCG2, APOE, LEPR, LXN, and TSPAN13. CONCLUSION: The up regulation of RAB3B may play an important role in the chemoresistance and metastatic potential of CSLCs.

[Questionnaire Survey of Treatment for Elderly Breast Cancer in Yamaguchi Prefecture].

A questionnaire survey was conducted by 17 doctors from 14 hospitals regarding treating elderly breast cancer in Yamaguchi Prefecture. The survey items are the implementation status of the geriatric assessment(GA)for the elderly, the state at the start of treatment(fit/vulnerable/frail), and the setting of restrictions on the indication of surgery and drug treatment (endocrine therapy/chemotherapy/molecular targeted therapy). Only one institution(6%)was used for GA; the tools used were the G8 and Charlson comorbidity index. Regarding surgical treatment, most facilities did not set restrictions according to age or condition. Endocrine and molecular-targeted therapies(anti-HER drugs)are highly tolerated, and most facilities do not have age restrictions. On the other hand, 40% of the respondents set age restrictions on chemotherapy. Four(24%) therapists said they would limit their age to 70 to 75 if the patient had a frail condition. These results tended to be similar to the reports of NCD-registered elderly breast cancer treatment.

[Tumor Immunogenicity and Immune Checkpoint Inhibitors].

Cancer immunotherapy including immune checkpoint inhibitors(ICIs)have established itself as the fourth cancer therapy. However, the response rate of ICIs is still only about 20%, and tumors resistant to ICIs are often so-called"cold-tumor"with low tumor immunogenicity. Therefore, research and development is being conducted worldwide on how to convert cold- tumors into hot-tumors with high immunogenicity. In this paper, we review the relationship between tumor immunogenicity and ICI, as well as therapeutic methods to enhance tumor immunogenicity, and introduce our research about novel cancer peptide vaccination therapy.

[Surgical Resection of Gastric GIST Liver Metastasis with Giant Cystic Mass-A Case Report].

The patient is a woman in her 80s who underwent a partial gastrectomy for a gastric GIST 14 years ago. This time, she presented our department with upper abdominal distention and computed tomography revealed an 18 cm-sized cystic lesion in the left lobe of the liver. Since a nodule enhancement was observed in the cyst, malignant disease such as hepatic cystadenocarcinoma could not be ruled out and surgical resection was performed. Pathological examination revealed liver metastasis of gastric GIST. In Japan, only 14 cases have been reported showing such late recurrence with liver metastasis more than 10 years after resection of a primary tumor, including our case. In addition, the cystic finding in this case made preoperative diagnosis difficult because a needle biopsy could not be performed to obtain a pathological diagnosis.

[A Case in Which FOLFOXIRI Was Useful as Preoperative Chemotherapy for Locally Advanced Rectal Cancer with Difficulty in Securing CRM].

The patient is a 65-year-old woman. Colonoscopy performed for close examination of constipation and lower abdominal pain revealed a circumferential type 3 lesion in the rectum Ra. A CT scan showed invasion of the primary lesion into the extramural and sacral front and multiple metastases in the mesorectal lymph nodes but no distant metastasis. Staging laparoscopy was performed. As the mesorectum around the primary lesion was tightly adherent, it was difficult to R0 resection; hence, only construction of colostomy was performed. We have introduced chemotherapy(FOLFOXIRI plus bevacizumab therapy), and 4 courses were administered. Post-treatment CT scan showed that the peri-invasiveness of the primary tumor had disappeared and the enlarged lymph nodes had shrunk. Furthermore, SUVmax of PET-CT for main lesion was decreased, dramatically. On day 109 after the initial surgery, laparoscopic low anterior resection was performed. Although the left hypogastric nerve was resected, other areas could be dissected and R0 resection could be performed. FOLFOXIRI therapy has shown good early-tumor shrinkage and depth of response and may be useful for patients with locally advanced rectal cancer who have difficulty securing circumferential resection margin(CRM).

[Questionnaire Survey of Treatment Strategies for Gastric Cancer with Peritoneal Dissemination in Yamaguchi Prefecture].

The questionnaire survey was conducted on treatment strategies for gastric cancer with peritoneal dissemination at 7 institutions, including 5 designated cancer hospitals in Yamaguchi prefecture. Staging laparotomy was performed at 6 out of 7 institutions. Six out of 7 institutions selected the treatment strategy for P0CY1 cases", upfront resection and adjuvant therapy". The doublet chemotherapy was performed by S-1 plus platinum or taxane. Surgical treatment for P1 cases, conversion gastrectomy was considered at all institutions when it was judged that R0 resection was possible after induction chemotherapy. Chemotherapy for P1 cases was treated according to the guidelines at all institutions, and the regimen was not changed depending on the peritoneal dissemination.

Novel adjuvant dendritic cell therapy with transfection of heat-shock protein 70 messenger RNA for patients with hepatocellular carcinoma: a phase I/II prospective randomized controlled clinical trial.

INTRODUCTION: A proteomic analysis of hepatocellular carcinoma (HCC) has revealed that Heat Shock Protein 70 (HSP70) is among the cancer antigen proteins of HCC. Moreover, we confirmed that HSP70 was highly expressed in HCC by immunohistochemical staining. Based on these results, we developed an HSP70 mRNA-transfected dendritic cell (DC) therapy for treating unresectable or recurrent HCC, and the phase I trial was completed successfully. Thus, we aimed to investigate the safety and efficacy of this therapy as a postoperative adjuvant treatment after curative resection for HCC to prevent recurrence by conducting a phase I/II randomized controlled clinical trial. METHODS: Patients (n = 45) with resectable HCC of stages II-IVa were registered and randomly assigned into two groups (DC group: 31 patients, control group: 14 patients) before surgery. The primary endpoint was disease-free survival (DFS), and the secondary endpoints were safety and overall survival. The DC therapy was initially administered at approximately 1 week after surgery, and twice every 3-4 weeks thereafter. RESULTS: No adverse events specific to the immunotherapy were observed in the DC group. There was no difference in DFS between the DC and control groups (p = 0.666). However, in the subgroup with HSP70-expressing HCC, DFS of the DC group tended to be better (p = 0.090) and OS of the DC group was significantly longer (p = 0.003) than those of the control group. CONCLUSION: The HSP70 mRNA-transfected DC therapy was performed safely as an adjuvant therapy. The prognosis of HSP70-expressing HCC cases could be expected to improve with this therapy.

Laparoscopic resection reduces superficial surgical site infection in liver surgery.

BACKGROUND: Laparoscopic liver resection is beneficial compared to open liver resection. This study aimed to evaluate whether laparoscopic liver resection could reduce postoperative infections. METHODS: This study included 125 and 115 patients with liver tumors who underwent open and pure laparoscopic partial resections or left lateral sectionectomies, respectively. Propensity score matching and stabilized inverse probability of treatment weighting were carried out to compare the postoperative infectious complication rates between the two groups. RESULTS: Patients with tumors located in Couinaud segment 1, 7, or 8; with tumors adjacent to major vessels; or who underwent repeated resections were more likely to receive open resection. After propensity score matching, the superficial incisional surgical site infection rate tended to be lower in the laparoscopic liver resection group than in the open liver resection group. Moreover, overall infectious complication rate and superficial incisional surgical site infection rate were lower in the laparoscopic group (the cohort formed by the stabilized inverse probability of treatment weighting). CONCLUSIONS: Using the laparoscopic approach for partial resections and left lateral sectionectomies for liver tumors, the superficial incisional surgical site infection rate could be reduced.

Hepatic artery resection and reconstruction using the right gastroepiploic artery during pancreaticoduodenectomy in advanced pancreatic cancer.

PURPOSE: Surgical resection is the only curative treatment for pancreatic cancer. Arterial resection and reconstruction during pancreaticoduodenectomy for advanced pancreatic cancer remain controversial due to a high rate of complications. METHODS: We report two cases of pancreatic cancer with hepatic artery resection and reconstruction using the right gastroepiploic artery during pancreaticoduodenectomy after neoadjuvant therapy. RESULTS: The patients underwent pancreaticoduodenectomy with resection of the right hepatic and common hepatic arteries. Achieving direct anastomosis was difficult; therefore, we planned hepatic artery reconstruction using the right gastroepiploic artery. We performed the reconstruction using an interrupted suture with end-to-end anastomosis. The first patient developed a postoperative pancreatic fistula, while the postoperative course of the second patient was uneventful. However, there were no adverse events related to the arterial reconstruction. R0 resection was achieved, and postoperative computed tomography revealed good patency of the reconstructed artery. CONCLUSION: Hepatic artery reconstruction using the right gastroepiploic artery in pancreatic cancer might be technically safe and might become one of the alternative options.

Change in antimicrobial susceptibility of pathogens isolated from surgical site infections over the past decade in Japanese nation-wide surveillance study.

Inappropriate antimicrobial therapy for surgical site infections (SSIs) can lead to poor outcomes and an increased risk of antibiotic resistance. A nationwide survey was conducted in Japan from 2018 to 2019 to investigate the antimicrobial susceptibility of pathogens isolated from SSIs. The data were compared with those obtained in 2010 and 2014-2015 surveillance studies. Although the rate of detection of extended-spectrum ß-lactamase producing strains of Escherichia coli was increased from 9.5% in 2010 to 23% in 2014-2015, the incidence decreased to 8.7% in 2018-2019. Although high susceptibility rates were detected to piperacillin/tazobactam (TAZ), the geometric mean MICs were substantially higher than to meropenem (2.67 vs 0.08 µg/mL). By contrast, relatively low geometric mean MICs (0.397 µg/mL) were demonstrated for ceftolozane/TAZ. Although the MRSA incidence rate decreased from 72% in the first surveillance to 53% in the second, no further decrease was detected in 2018-2019. For the Bacteroides fragilis group species, low levels of susceptibility were observed for moxifloxacin (65.3%), cefoxitin (65.3%), and clindamycin (CLDM) (38.9%). In particular, low susceptibility against cefoxitin was demonstrated in non-fragilis Bacteroides, especially B. thetaiotaomicron. By contrast, low susceptibility rates against CLDM were demonstrated in both B. fragilis and non-fragilis Bacteroides species, and a steady decrease in susceptibility throughout was observed (59.3% in 2010, 46.9% in 2014-2015, and 38.9% in 2018-2019). In conclusion, Japanese surveillance data revealed no significant lowering of antibiotic susceptibility over the past decade in organisms commonly associated from SSIs, with the exception of the B. fragilis group.

Determining the protective characteristics and risk factors for the development of anastomotic leakage after low anterior resection for rectal cancer.

PURPOSE: Anastomotic leakage is one of the most serious postoperative complications associated with surgery for rectal cancer. The present study aimed to identify the protective characteristics and risk factors associated with anastomotic leakage after low anterior resection for rectal cancer. METHODS: This was a retrospective, single-center study conducted between January 2009 and December 2017 at our institution. In total, 136 rectal cancer patients who underwent low anterior resection were included in the study. We analyzed preoperative and intraoperative factors. In addition, the pelvic dimensions were measured using computed tomography in all cases. RESULTS: Among the 136 patients, anastomotic leakage occurred in 21 (15.4%), including 18 males and 3 females. The median body mass index was 21.1 kg/m2. The construction of a covering stoma was found to be a protective factor. In addition, the operation time (≥ 373 min), intraoperative blood loss (≥ 105 ml), and size of the pelvic inlet (≥ 113 mm) were identified as risk factors for anastomotic leakage. CONCLUSION: The construction of a covering stoma was a possible protective factor. However, a longer operation time, higher intraoperative blood loss, and larger pelvic inlet dimensions were possible risk factors for developing anastomotic leakage after low anterior resection in patients with rectal cancer.