The oxygen-rich postnatal environment induces cardiomyocyte cell-cycle arrest through DNA damage response.

The mammalian heart has a remarkable regenerative capacity for a short period of time after birth, after which the majority of cardiomyocytes permanently exit cell cycle. We sought to determine the primary postnatal event that results in cardiomyocyte cell-cycle arrest. We hypothesized that transition to the oxygen-rich postnatal environment is the upstream signal that results in cell-cycle arrest of cardiomyocytes. Here, we show that reactive oxygen species (ROS), oxidative DNA damage, and DNA damage response (DDR) markers significantly increase in the heart during the first postnatal week. Intriguingly, postnatal hypoxemia, ROS scavenging, or inhibition of DDR all prolong the postnatal proliferative window of cardiomyocytes, whereas hyperoxemia and ROS generators shorten it. These findings uncover a protective mechanism that mediates cardiomyocyte cell-cycle arrest in exchange for utilization of oxygen-dependent aerobic metabolism. Reduction of mitochondrial-dependent oxidative stress should be an important component of cardiomyocyte proliferation-based therapeutic approaches.

Adducin Regulates Sarcomere Disassembly During Cardiomyocyte Mitosis.

BACKGROUND: Recent interest in understanding cardiomyocyte cell cycle has been driven by potential therapeutic applications in cardiomyopathy. However, despite recent advances, cardiomyocyte mitosis remains a poorly understood process. For example, it is unclear how sarcomeres are disassembled during mitosis to allow the abscission of daughter cardiomyocytes. METHODS: Here, we use a proteomics screen to identify adducin, an actin capping protein previously not studied in cardiomyocytes, as a regulator of sarcomere disassembly. We generated many adeno-associated viruses and cardiomyocyte-specific genetic gain-of-function models to examine the role of adducin in neonatal and adult cardiomyocytes in vitro and in vivo. RESULTS: We identify adducin as a regulator of sarcomere disassembly during mammalian cardiomyocyte mitosis. α/γ-adducins are selectively expressed in neonatal mitotic cardiomyocytes, and their levels decline precipitously thereafter. Cardiomyocyte-specific overexpression of various splice isoforms and phospho-isoforms of α-adducin in identified Thr445/Thr480 phosphorylation of a short isoform of α-adducin as a potent inducer of neonatal cardiomyocyte sarcomere disassembly. Concomitant overexpression of this α-adducin variant along with γ-adducin resulted in stabilization of the adducin complex and persistent sarcomere disassembly in adult mice, which is mediated by interaction with α-actinin. CONCLUSIONS: These results highlight an important mechanism for coordinating cytoskeletal morphological changes during cardiomyocyte mitosis.

Prolonged Myocardial Regenerative Capacity in Neonatal Opossum.

BACKGROUND: Early neonates of both large and small mammals are able to regenerate the myocardium through cardiomyocyte proliferation for only a short period after birth. This myocardial regenerative capacity declines in parallel with withdrawal of cardiomyocytes from the cell cycle in the first few postnatal days. No mammalian species examined to date has been found capable of a meaningful regenerative response to myocardial injury later than 1 week after birth. METHODS: We examined cardiomyocyte proliferation in neonates of the marsupial opossum (Monodelphis domestica) by immunostaining at various times after birth. The regenerative capacity of the postnatal opossum myocardium was assessed after either apex resection or induction of myocardial infarction at postnatal day 14 or 29, whereas that of the postnatal mouse myocardium was assessed after myocardial infarction at postnatal day 7. Bioinformatics data analysis, immunofluorescence staining, and pharmacological and genetic intervention were applied to determine the role of AMPK (5'-AMP-activated protein kinase) signaling in regulation of the mammalian cardiomyocyte cell cycle. RESULTS: Opossum neonates were found to manifest cardiomyocyte proliferation for at least 2 weeks after birth at a frequency similar to that apparent in early neonatal mice. Moreover, the opossum heart at postnatal day 14 showed substantial regenerative capacity both after apex resection and after myocardial infarction injury, whereas this capacity had diminished by postnatal day 29. Transcriptomic and immunofluorescence analyses indicated that AMPK signaling is activated in postnatal cardiomyocytes of both opossum and mouse. Pharmacological or genetic inhibition of AMPK signaling was sufficient to extend the postnatal window of cardiomyocyte proliferation in both mouse and opossum neonates as well as of cardiac regeneration in neonatal mice. CONCLUSIONS: The marsupial opossum maintains cardiomyocyte proliferation and a capacity for myocardial regeneration for at least 2 weeks after birth. As far as we are aware, this is the longest postnatal duration of such a capacity among mammals examined to date. AMPK signaling was implicated as an evolutionarily conserved regulator of mammalian postnatal cardiomyocyte proliferation.

Hypoxia induces heart regeneration in adult mice.

The adult mammalian heart is incapable of regeneration following cardiomyocyte loss, which underpins the lasting and severe effects of cardiomyopathy. Recently, it has become clear that the mammalian heart is not a post-mitotic organ. For example, the neonatal heart is capable of regenerating lost myocardium, and the adult heart is capable of modest self-renewal. In both of these scenarios, cardiomyocyte renewal occurs via the proliferation of pre-existing cardiomyocytes, and is regulated by aerobic-respiration-mediated oxidative DNA damage. Therefore, we reasoned that inhibiting aerobic respiration by inducing systemic hypoxaemia would alleviate oxidative DNA damage, thereby inducing cardiomyocyte proliferation in adult mammals. Here we report that, in mice, gradual exposure to severe systemic hypoxaemia, in which inspired oxygen is gradually decreased by 1% and maintained at 7% for 2 weeks, results in inhibition of oxidative metabolism, decreased reactive oxygen species production and oxidative DNA damage, and reactivation of cardiomyocyte mitosis. Notably, we find that exposure to hypoxaemia 1 week after induction of myocardial infarction induces a robust regenerative response with decreased myocardial fibrosis and improvement of left ventricular systolic function. Genetic fate-mapping analysis confirms that the newly formed myocardium is derived from pre-existing cardiomyocytes. These results demonstrate that the endogenous regenerative properties of the adult mammalian heart can be reactivated by exposure to gradual systemic hypoxaemia, and highlight the potential therapeutic role of hypoxia in regenerative medicine.

Neoadjuvant S-1 With Concurrent Radiotherapy Followed by Surgery for Borderline Resectable Pancreatic Cancer: A Phase II Open-label Multicenter Prospective Trial (JASPAC05).

OBJECTIVE: This study assessed whether neoadjuvant chemoradiotherapy (CRT) with S-1 increases the R0 resection rate in BRPC. SUMMARY OF BACKGROUND DATA: Although a multidisciplinary approach that includes neoadjuvant treatment has been shown to be a better strategy for BRPC than upfront resection, a standard treatment for BRPC has not been established. METHODS: A multicenter, single-arm, phase II study was performed. Patients who fulfilled the criteria for BRPC received S-1 (40 mg/m 2 bid) and concurrent radiotherapy (50.4 Gy in 28 fractions) before surgery. The primary endpoint was the R0 resection rate. At least 40 patients were required, with a 1-sided α = 0.05 and ß = 0.05 and expected and threshold values for the primary endpoint of 30% and 10%, respectively. RESULTS: Fifty-two patients were eligible, and 41 were confirmed to have definitive BRPC by a central review. CRT was completed in 50 (96%) patients and was well tolerated. The rate of grade 3/4 toxicity with CRT was 43%. The R0 resection rate was 52% among the 52 eligible patients and 63% among the 41 patients who were centrally confirmed to have BRPC. Postoperative grade III/IV adverse events according to the Clavien-Dindo classification were observed in 7.5%. Among the 41 centrally confirmed BRPC patients, the 2-year overall survival rate and median overall survival duration were 58% and 30.8 months, respectively. CONCLUSIONS: S-1 and concurrent radiotherapy seem to be feasible and effective at increasing the R0 resection rate and improving survival in patients with BRPC. TRIAL REGISTRATION: UMIN000009172.

Phase I/II study of streptozocin monotherapy in Japanese patients with unresectable or metastatic gastroenteropancreatic neuroendocrine tumors.

BACKGROUND: This phase I/II study was conducted to evaluate the efficacy, safety and pharmacokinetics of streptozocin (STZ) in Japanese patients with unresectable or metastatic gastroenteropancreatic neuroendocrine tumors. METHODS: Twenty-two patients received up to 4 cycles of intravenous STZ at either 500 mg/m2 once daily for 5 consecutive days every 6 weeks (daily regimen) or at 1000-1500 mg/m2 once weekly for 6 weeks (weekly regimen). Tumor response was evaluated using the modified RECIST criteria ver. 1.1, and adverse events were assessed by grade according to the National Cancer Institute CTCAE (ver. 4.0). RESULTS: Fourteen (63.6%) patients completed the study protocol. No patients had complete response; partial response in 2 (9.1%), stable disease in 17 (77.3%), non-complete response/non-progressive disease in 2 (9.1%) and only 1 (4.5%) had non-evaluable disease. Excluding the latter, the response rate in the daily and weekly regimens was 6.7% (1/15) and 16.7% (1/6), respectively, with an overall response rate of 9.5% (2/21). However, the best overall response in each patient showed that the disease control rate was 100%.Adverse events occurred in all 22 patients, including 17 grade 3 adverse events in 11 patients; however, no grade 4 or 5 adverse events were reported. Prophylactic hydration and antiemetic treatment reduced the severity and incidence of nephrotoxicity, nausea and vomiting. Plasma STZ concentrations decreased rapidly after termination of infusion, with a half-life of 32-40 min. Neither repeated administration nor dose increases affected pharmacokinetic parameters. CONCLUSIONS: STZ may be a useful option for Japanese patients with unresectable or metastatic gastroenteropancreatic neuroendocrine tumors.

Hypoxia fate mapping identifies cycling cardiomyocytes in the adult heart.

Although the adult mammalian heart is incapable of meaningful functional recovery following substantial cardiomyocyte loss, it is now clear that modest cardiomyocyte turnover occurs in adult mouse and human hearts, mediated primarily by proliferation of pre-existing cardiomyocytes. However, fate mapping of these cycling cardiomyocytes has not been possible thus far owing to the lack of identifiable genetic markers. In several organs, stem or progenitor cells reside in relatively hypoxic microenvironments where the stabilization of the hypoxia-inducible factor 1 alpha (Hif-1α) subunit is critical for their maintenance and function. Here we report fate mapping of hypoxic cells and their progenies by generating a transgenic mouse expressing a chimaeric protein in which the oxygen-dependent degradation (ODD) domain of Hif-1α is fused to the tamoxifen-inducible CreERT2 recombinase. In mice bearing the creERT2-ODD transgene driven by either the ubiquitous CAG promoter or the cardiomyocyte-specific α myosin heavy chain promoter, we identify a rare population of hypoxic cardiomyocytes that display characteristics of proliferative neonatal cardiomyocytes, such as smaller size, mononucleation and lower oxidative DNA damage. Notably, these hypoxic cardiomyocytes contributed widely to new cardiomyocyte formation in the adult heart. These results indicate that hypoxia signalling is an important hallmark of cycling cardiomyocytes, and suggest that hypoxia fate mapping can be a powerful tool for identifying cycling cells in adult mammals.

Increasing Heme Oxygenase-1-Expressing Macrophages Indicates a Tendency of Poor Prognosis in Advanced Colorectal Cancer.

BACKGROUND: Many cancers express heme oxygenase-1 -(HO-1) at a higher frequency than healthy tissues, and this elevated expression is associated with cancer prognosis. Here, we aim to clarify the correlation between HO-1-expressing macrophage numbers and clinicopathological parameters of advanced colorectal cancer. MATERIALS AND METHODS: Formalin-fixed and paraffin-embedded tissues of patients with advanced colorectal cancer were used. To detect HO-1 expression in macrophages, immunohistochemistry was performed. The number of positive cells was measured. Furthermore, HO-1 mRNA in colorectal cancer was examined by reverse transcription polymerase chain reaction. RESULTS: Among the HO-1-negative and HO-1-positive groups, 58.02 and 85.00% of cases, respectively, were positive for lymph node metastasis. The disease-free survival (DFS) time was significantly shorter (p < 0.05) in the -HO-1-positive group (2.44 years) than in the HO-1-negative group (4.09 years). However, according to the Cox proportional-hazards regression model, the HO-1-positive group could not be a risk factor of poor prognosis. HO-1 mRNA expression was confirmed in colorectal normal and cancer tissues. CONCLUSION: In this study, the correlation between HO-1-expressing macrophages and clinicopathological parameters in the tumor microenvironment of colorectal cancer was studied for the first time, and the expression was associated with lymph node metastasis and shortening of DFS.

Differential expression of estrogen receptor-α on follicular dendritic cells from patients with grade 1-2 and grade 3 follicular lymphoma.

Hormone therapy has been used for patients with estrogen receptor alpha (ERα)-positive breast cancers. Recently, some studies reported the expression of ERα on neoplastic cells from B-cell lymphomas. However, there has been only one report of ERα expression on the follicular dendritic cells (FDCs) that structurally and functionally support the microenvironment of follicular lymphomas (FLs). The objective of this study was to investigate the frequency of ERα expression on FDCs in nonneoplastic reactive lymphoid tissues and to compare the frequency of ERα expression on FDCs in the axillary lymph nodes between patients with and without antiestrogen therapy and among patients with grades 1-3 of FL. Reverse transcription-polymerase chain reaction was performed to detect ERα mRNA in FL. In nonneoplastic germinal centers (GCs) from patients with tonsillitis or reactive lymphadenitis, ERα was expressed in the light zone. ERα-positive cells strongly correlated with the width of GCs (rs  = 0.81, P < 0.01) and the CD21-positive (rs  = 0.69, P < 0.01) and CD23-positive (rs  = 0.83, P < 0.01) FDC meshwork. The axillary lymph nodes had fewer ERα-positive cells, smaller GCs, and a looser CD21- and CD23-positive FDC meshwork with hormone therapy than without hormone therapy (P < 0.01). Neoplastic follicles of G1-2 FL had more ERα-positive cells and a larger CD23+ FDC meshwork than those of G3 FL (P < 0.01). ERα mRNA was detected in both G1-2 FL and G3 FL by reverse transcription-polymerase chain reaction. In conclusion, these results suggested that antiestrogen hormone therapy may decrease the number of ERα-positive FDCs and that the responses mediated by the estrogen-ERα interaction on FDCs may differ between G1-2 FL and G3 FL.

Meis1 regulates postnatal cardiomyocyte cell cycle arrest.

The neonatal mammalian heart is capable of substantial regeneration following injury through cardiomyocyte proliferation. However, this regenerative capacity is lost by postnatal day 7 and the mechanisms of cardiomyocyte cell cycle arrest remain unclear. The homeodomain transcription factor Meis1 is required for normal cardiac development but its role in cardiomyocytes is unknown. Here we identify Meis1 as a critical regulator of the cardiomyocyte cell cycle. Meis1 deletion in mouse cardiomyocytes was sufficient for extension of the postnatal proliferative window of cardiomyocytes, and for re-activation of cardiomyocyte mitosis in the adult heart with no deleterious effect on cardiac function. In contrast, overexpression of Meis1 in cardiomyocytes decreased neonatal myocyte proliferation and inhibited neonatal heart regeneration. Finally, we show that Meis1 is required for transcriptional activation of the synergistic CDK inhibitors p15, p16 and p21. These results identify Meis1 as a critical transcriptional regulator of cardiomyocyte proliferation and a potential therapeutic target for heart regeneration.

Submicroscopic deletions at 13q32.1 cause congenital microcoria.

Congenital microcoria (MCOR) is a rare autosomal-dominant disorder characterized by inability of the iris to dilate owing to absence of dilator pupillae muscle. So far, a dozen MCOR-affected families have been reported worldwide. By using whole-genome oligonucleotide array CGH, we have identified deletions at 13q32.1 segregating with MCOR in six families originating from France, Japan, and Mexico. Breakpoint sequence analyses showed nonrecurrent deletions in 5/6 families. The deletions varied from 35 kbp to 80 kbp in size, but invariably encompassed or interrupted only two genes: TGDS encoding the TDP-glucose 4,6-dehydratase and GPR180 encoding the G protein-coupled receptor 180, also known as intimal thickness-related receptor (ITR). Unlike TGDS which has no known function in muscle cells, GPR180 is involved in the regulation of smooth muscle cell growth. The identification of a null GPR180 mutation segregating over two generations with iridocorneal angle dysgenesis, which can be regarded as a MCOR endophenotype, is consistent with the view that deletions of this gene, with or without the loss of elements regulating the expression of neighboring genes, are the cause of MCOR.

Decomposition products of glycidyl esters of fatty acids by heating.

In this study, decomposition products of glycidyl palmitate (GP) of fatty acids heated at high temperature such as deep frying were investigated. When GP and tripalmitin (TP) were heated at 180 and 200 °C, they were decreased with heating time. The weight of GP was less than that of TP, although both GP and TP were converted to polar compounds after heating. The decomposition rate of GP was higher than TP. Both GP and TP produced considerable amounts of hydrocarbons and aldehydes during heating. Aldehydes produced from GP and TP included saturated aldehydes with carbon chain length of 3-10, while hydrocarbons consisted of carbon chain length of 8-15. It was observed that major hydrocarbons produced from GP during heating were pentadecane. Moreover, the level of carbon dioxide (CO2) released from GP was higher than that of TP. It was suggested that fatty acids in GE might be susceptible to decarboxylation. From these results, GP might be quickly decomposed to hydrocarbons, aldehydes and CO2 besides polar compounds by heating, in comparison with TP.

Genetic defects in a His-Purkinje system transcription factor, IRX3, cause lethal cardiac arrhythmias.

AIM: Ventricular fibrillation (VF), the main cause of sudden cardiac death (SCD), occurs most frequently in the acute phase of myocardial infarction: a certain fraction of VF, however, develops in an apparently healthy heart, referred as idiopathic VF. The contribution of perturbation in the fast conduction system in the ventricle, the His-Purkinje system, for idiopathic VF has been implicated, but the underlying mechanism remains unknown. Irx3/IRX3 encodes a transcription factor specifically expressed in the His-Purkinje system in the heart. Genetic deletion of Irx3 provides a mouse model of ventricular fast conduction disturbance without anatomical or contraction abnormalities. The aim of this study was to examine the link between perturbed His-Purkinje system and idiopathic VF in Irx3-null mice, and to search for IRX3 genetic defects in idiopathic VF patients in human. METHODS AND RESULTS: Telemetry electrocardiogram recording showed that Irx3-deleted mice developed frequent ventricular tachyarrhythmias mostly at night. Ventricular tachyarrhythmias were enhanced by exercise and sympathetic nerve activation. In human, the sequence analysis of IRX3 exons in 130 probands of idiopathic VF without SCN5A mutations revealed two novel IRX3 mutations, 1262G>C (R421P) and 1453C>A (P485T). Ventricular fibrillation associated with physical activities in both probands with IRX3 mutations. In HL-1 cells and neonatal mouse ventricular myocytes, IRX3 transfection up-regulated SCN5A and connexin-40 mRNA, which was attenuated by IRX3 mutations. CONCLUSION: IRX3 genetic defects and resultant functional perturbation in the His-Purkinje system are novel genetic risk factors of idiopathic VF, and would improve risk stratification and preventive therapy for SCD in otherwise healthy hearts.

A case of pancreatic intraepithelial neoplasia-3 with autoimmune pancreatitis.

We report a case of pancreatic intraepithelial neoplasia-3 (PanIN-3) with autoimmune pancreatitis (AIP). The patient, a 75-year-old man, had been diagnosed to have AIP with stenosis of the main pancreatic duct. After six years, computed tomography demonstrated dilatation of the main pancreatic duct in the mid-pancreas. Although we could not confirm the presence of any pancreatic tumor on the basis of imaging modalities alone, cytological examination of the pancreatic juice obtained by endoscopic retrograde pancreatography revealed atypical cells. Therefore, we performed pancreatoduodenectomy and obtained a pathologic diagnosis of PanIN-3 with AIP. The present case is informative in the context of pancreatic carcinogenesis in AIP.

Risk Model for Distal Gastrectomy When Treating Gastric Cancer on the Basis of Data From 33,917 Japanese Patients Collected Using a Nationwide Web-based Data Entry System.

OBJECTIVE: To establish a risk model for distal gastrectomy in Japanese patients with gastric cancer. BACKGROUND: Risk stratification for distal gastrectomy in Japanese patients with gastric cancer improves surgical outcomes. METHODS: The National Clinical Database was constructed for risk determination in gastric cancer-related gastrectomy among Japanese individuals. Data from 33,917 gastric cancer cases (1737 hospitals) were used. The primary outcomes were 30-day and operative mortalities. Data were randomly assigned to risk model development (27,220 cases) and test validation (6697 cases) subsets. Stepwise selection was used for constructing 30-day and operative mortality logistic models. RESULTS: The 30-day, in-hospital, and operative mortality rates were 0.52%, 1.16%, and 1.2%, respectively. The morbidity was 18.3%. The 30-day and operative mortality models included 17 and 21 risk factors, respectively. Thirteen variables overlapped: age, need for total assistance in activities of daily living preoperatively or within 30 days after surgery, cerebrovascular disease history, more than 10% weight loss, uncontrolled ascites, American Society of Anesthesiologists score (≥ class 3), white blood cell count more than 12,000/µL or 11,000/µL, anemia (hemoglobin: males, <13.5 g/dL; females, <12.5 g/dL; or hematocrit: males, <37%; females <32%), serum albumin less than 3.5 or 3.8 g/dL, alkaline phosphatase more than 340 IU/L, serum creatinine more than 1.2 mg/dL, serum Na less than 135 mEq/L, and prothrombin time-international normalized ratio more than 1.25 or 1.1. The C-indices for the 30-day and operative mortalities were 0.785 (95% confidence interval, 0.705-0.865; P < 0.001) and 0.798 (95% confidence interval, 0.746-0.851; P < 0.001), respectively. CONCLUSIONS: The risk model developed using nationwide Japanese data on distal gastrectomy in gastric cancer can predict surgical outcomes.

Surgical risk model for acute diffuse peritonitis based on a Japanese nationwide database: an initial report on the surgical and 30-day mortality.

PURPOSE: Acute diffuse peritonitis (ADP) is an important surgical complication associated with high morbidity and mortality; however, the risk factors associated with a poor outcome have remained controversial. This study aimed in collecting integrated data using a web-based national database system to build a risk model for mortality after surgery for ADP. METHODS: We included cases registered in the National Clinical Database in Japan. After data cleanup, 8,482 surgical cases of ADP from 1,285 hospitals treated between January 1 and December 31, 2011 were analyzed. RESULTS: The raw 30-day and surgical mortality rates were 9.0 and 14.1 %, respectively. The odds ratios (>2.0) for 30-day mortality were as follows: American Society of Anesthesiologists (ASA) class 3, 2.69; ASA class 4, 4.28; ASA class 5, 8.65; previous percutaneous coronary intervention (PCI), 2.05; previous surgery for peripheral vascular disease (PVD), 2.45 and disseminated cancer, 2.16. The odds ratios (>2.0) for surgical mortality were as follows: ASA class 3, 2.27; ASA class 4, 4.67; ASA class 5, 6.54, and disseminated cancer, 2.09. The C-indices of 30-day and surgical mortality were 0.851 and 0.852, respectively. CONCLUSION: This is the first report of risk stratification after surgery for ADP using a nationwide surgical database. This system could be useful to predict the outcome of surgery for ADP and for evaluations and benchmark performance studies.

A pancreaticoduodenectomy risk model derived from 8575 cases from a national single-race population (Japanese) using a web-based data entry system: the 30-day and in-hospital mortality rates for pancreaticoduodenectomy.

OBJECTIVE: To create a mortality risk model after pancreaticoduodenectomy (PD) using a Web-based national database system. BACKGROUND: PD is a major gastroenterological surgery with relatively high mortality. Many studies have reported factors to analyze short-term outcomes. SUBJECTS AND METHODS: After initiation of National Clinical Database, approximately 1.2 million surgical cases from more than 3500 Japanese hospitals were collected through a Web-based data entry system. After data cleanup, 8575 PD patients (mean age, 68.2 years) recorded in 2011 from 1167 hospitals were analyzed using variables and definitions almost identical to those of American College of Surgeons-National Surgical Quality Improvement Program. RESULTS: The 30-day postoperative and in-hospital mortality rates were 1.2% and 2.8% (103 and 239 patients), respectively. Thirteen significant risk factors for in-hospital mortality were identified: age, respiratory distress, activities of daily living within 30 days before surgery, angina, weight loss of more than 10%, American Society of Anesthesiologists class of greater than 3, Brinkman index of more than 400, body mass index of more than 25 kg/m, white blood cell count of more than 11,000 cells per microliter, platelet count of less than 120,000 per microliter, prothrombin time/international normalized ratio of more than 1.1, activated partial thromboplastin time of more than 40 seconds, and serum creatinine levels of more than 3.0 mg/dL. Five variables, including male sex, emergency surgery, chronic obstructive pulmonary disease, bleeding disorders, and serum urea nitrogen levels of less than 8.0 mg/dL, were independent variables in the 30-day mortality group. The overall PD complication rate was 40.0%. Grade B and C pancreatic fistulas in the International Study Group on Pancreatic Fistula occurred in 13.2% cases. The 30-day and in-hospital mortality rates for pancreatic cancer were significantly lower than those for nonpancreatic cancer. CONCLUSIONS: We conducted the reported risk stratification study for PD using a nationwide surgical database. PD outcomes in the national population were satisfactory, and the risk model could help improve surgical practice quality.

A risk model for esophagectomy using data of 5354 patients included in a Japanese nationwide web-based database.

OBJECTIVE: This study aimed to create a risk model of mortality associated with esophagectomy using a Japanese nationwide database. METHODS: A total of 5354 patients who underwent esophagectomy in 713 hospitals in 2011 were evaluated. Variables and definitions were virtually identical to those adopted by the American College of Surgeons National Surgical Quality Improvement Program. RESULTS: The mean patient age was 65.9 years, and 84.3% patients were male. The overall morbidity rate was 41.9%. Thirty-day and operative mortality rates after esophagectomy were 1.2% and 3.4%, respectively. Overall morbidity was significantly higher in the minimally invasive esophagectomy group than in the open esophagectomy group (44.3% vs 40.8%, P = 0.016). The odds ratios for 30-day mortality in patients who required preoperative assistance in activities of daily living (ADL), those with a history of smoking within 1 year before surgery, and those with weight loss more than 10% within 6 months before surgery were 4.2, 2.6, and 2.4, respectively. The odds ratios for operative mortality in patients who required preoperative assistance in ADL, those with metastasis/relapse, male patients, and those with chronic obstructive pulmonary disease were 4.7, 4.5, 2.3, and 2.1, respectively. CONCLUSIONS: This study was the first, as per our knowledge, to perform risk stratification for esophagectomy using a Japanese nationwide database. The 30-day and operative mortality rates were relatively lower than those in previous reports. The risk models developed in this study may contribute toward improvements in quality control of procedures and creation of a novel scoring system.

Total gastrectomy risk model: data from 20,011 Japanese patients in a nationwide internet-based database.

OBJECTIVE: To construct a risk model for total gastrectomy outcomes using a nationwide Internet-based database. BACKGROUND: Total gastrectomy is a very common procedure in Japan. This procedure is among the most invasive gastrointestinal procedures and is known to carry substantial surgical risks. METHODS: The National Clinical Database was used to retrieve records on more than 1,200,000 surgical cases from 3500 hospitals in 2011. After data cleanup, 20,011 records from 1623 hospitals were analyzed for procedures performed between January 1, 2011, and December 31, 2011. RESULTS: The average patient age was 68.9 years; 73.7% were male. The overall morbidity was 26.2%, with a 30-day mortality rate of 0.9%, in-hospital mortality rate of 2.2%, and overall operative mortality rate of 2.3%. The odds ratios for 30-day mortality were as follows: ASA (American Society of Anesthesiologists) grade 4 or 5, 9.4; preoperative dialysis requirement, 3.9; and platelet count less than 50,000 per microliter, 3.1. The odds ratios for operative mortality were as follows: ASA grade 4 or 5, 5.2; disseminated cancer, 3.5; and alkaline phosphatase level of more than 600 IU/L, 3.1. The C-index of 30-day mortality and operative mortality was 0.811 (95% confidence interval [CI], 0.744-0.879) and 0.824 (95% CI, 0.781-0.866), respectively. CONCLUSIONS: We have performed the first reported risk stratification study for total gastrectomy, using a nationwide Internet-based database. The total gastrectomy outcomes in the nationwide population were satisfactory. The risk models that we have created will help improve the quality of surgical practice.