Value of E-PASS models for predicting postoperative morbidity and mortality in resection of perihilar cholangiocarcinoma and gallbladder carcinoma.

BACKGROUND: It has previously been reported that a general risk model, Estimation of Physiologic Ability and Surgical Stress (E-PASS), and its modified version, mE-PASS, had a high predictive power for postoperative mortality and morbidity in a variety of gastrointestinal surgeries. This study evaluated their utilities in proximal biliary carcinoma resection. METHODS: E-PASS variables were collected in patients undergoing resection of perihilar cholangiocarcinoma and gallbladder carcinoma in Japanese referral hospitals. RESULTS: Analysis of 125 patients with gallbladder cancer and 97 patients with perihilar cholangiocarcinoma (n = 222). Fifty-six patients (25%) underwent liver resection with either hemihepatectomy or extended hemihepatectomy. The E-PASS models showed a high discrimination power to predict in-hospital mortality; areas under the receiver operating characteristic curve (95% confidence intervals) were 0.85 (0.76-0.94) for E-PASS and 0.82 (0.73-0.91) for mE-PASS. The predicted mortality rates correlated with the severity of postoperative complications (Spearman's rank correlation coefficient: ρ = 0.51, P < 0.001 for E-PASS; ρ = 0.47, P < 0.001 for mE-PASS). CONCLUSIONS: The E-PASS models examined herein may accurately predict postoperative morbidity and mortality in proximal biliary carcinoma resection. These models will be useful for surgical decision-making, informed consent, and risk adjustments in surgical audits.

Preliminary study of surgical audit for overall survival following gastric cancer resection.

BACKGROUND: Previous studies for surgical audit have focused on short-term outcomes, such as perioperative mortality. There has been no gold standard how to evaluate quality of care for long-term outcomes in surgical oncology. This preliminary study aims to propose a method for surgical audit targeting long-term outcome following gastrectomy for gastric cancer. METHODS: We prospectively investigated a set of variables relating to physiologic conditions, tumor characteristics and operations in patients who underwent gastrectomy for gastric cancer between June 2005 and July 2008 in 18 referral hospitals in Japan. Overall survival (OS) is the endpoint. Cox hazard regression analysis was used to generate a model to predict OS. The calibration and discrimination power of the model were assessed using the Hosmer-Lemeshow (H-L) test and area under the receiver-operating characteristic curve (AUC), respectively. The ratio of observed-to-estimated 5-year OS rates (OE ratio) was defined as a measure of quality. RESULTS: Among 762 patients analyzed, 697 (91%) completed the 5-year follow-up. The constructed model for OS exhibited a good discrimination power (AUC, 95% confidence interval 0.89, 0.86-0.91), which was significantly better than that for the UICC stage (0.81, 0.77-0.84). This model also demonstrated a good calibration power (H-L: χ(2) = 27.2, df = 8, P = 0.77). The OE ratios among the participating hospitals revealed no significant variation between 0.74 and 1.1. CONCLUSIONS: The current study suggests the possibility of surgical audit for postoperative OS in gastric cancer. Further studies including high-volume centers will be necessary to validate this idea.

Experimental and numerical investigation of contact-area-limited doping for top-contact pentacene thin-film transistors with Schottky contact.

Effects of contact-area-limited doping for pentacene thin-film transistors with a bottom-gate, top-contact configuration were investigated. The increase in the drain current and the effective field-effect mobility was achieved by preparing hole-doped layers underneath the gold contact electrodes by coevaporation of pentacene and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), confirmed by using a thin-film organic transistor advanced simulator (TOTAS) incorporating Schottky contact with a thermionic field emission (TFE) model. Although the simulated electrical characteristics fit the experimental results well only in the linear regime of the transistor operation, the barrier height for hole injection and the gate-voltage-dependent hole mobility in the pentacene transistors were evaluated with the aid of the device simulation. This experimental data analysis with the simulation indicates that the highly-doped semiconducting layers prepared in the contact regions can enhance the charge carrier injection into the active semiconductor layer and concurrent trap filling in the transistor channel, caused by the mitigation of a Schottky energy barrier. This study suggests that both the contact-area-limited doping and the device simulation dealing with Schottky contact are indispensable in designing and developing high-performance organic thin-film transistors.

The EPOS-CC Score: An Integration of Independent, Tumor- and Patient-Associated Risk Factors to Predict 5-years Overall Survival Following Colorectal Cancer Surgery.

BACKGROUND: Surgical audit is an essential task for the estimation of postoperative outcome and comparison of quality of care. Previous studies on surgical audits focused on short-term outcomes, such as postoperative mortality. We propose a surgical audit evaluating long-term outcome following colorectal cancer surgery. The predictive model for this audit is designated as 'Estimation of Postoperative Overall Survival for Colorectal Cancer (EPOS-CC)'. METHODS: Thirty-one tumor-related and physiological variables were prospectively collected in 889 patients undergoing elective resection for colorectal cancer between April 2005 and April 2007 in 16 Japanese hospitals. Postoperative overall survival was assessed over a 5-years period. The EPOS-CC score was established by selecting significant variables in a uni- and multivariate analysis and allocating a risk-adjusted multiplication factor to each variable using Cox regression analysis. For validation, the EPOS-CC score was compared to the predictive power of UICC stage. Inter-hospital variability of the observed-to-estimated 5-years survival was assessed to estimate quality of care. RESULTS: Among the 889 patients, 804 (90%) completed the 5-years follow-up. Univariate analysis displayed a significant correlation with 5-years survival for 14 physiological and nine tumor-related variables (p < 0.005). Highly significant p-values below 0.0001 were found for age, ASA score, severe pulmonary disease, respiratory history, performance status, hypoalbuminemia, alteration of hemoglobin, serum sodium level, and for all histological variables except tumor location. Age, TNM stage, lymphatic invasion, performance status, and serum sodium level were independent variables in the multivariate analysis and were entered the EPOS-CC model for the prediction of survival. Risk-adjusted multiplication factors between 1.5 (distant metastasis) and 0.16 (serum sodium level) were accorded to the different variables. The predictive power of EPOS-CC was superior to the one of UICC stage; area under the curve 0.87, 95% CI 0.85-0.90 for EPOS-CC, and 0.80, 0.76-0.83 for UICC stage, p < 0.001. Quality of care did not differ between hospitals. CONCLUSIONS: The EPOS-CC score including the independent variables age, performance status, serum sodium level, TNM stage, and lymphatic invasion is superior to the UICC stage in the prediction of 5-years overall survival. This higher accuracy might be explained by the inclusion of physiological factors, thus also taking non-tumor-associated deaths into account. Furthermore, EPOS-CC score may compare quality of care among different institutions. Future studies are necessary to further evaluate this score and help improving the prediction of long-term survival following colorectal cancer surgery.

Evaluation of modified estimation of physiologic ability and surgical stress in patients undergoing surgery for choledochocystolithiasis.

BACKGROUND: The incidence of complicated choledochocystolithiasis is increasing with the aging of society in Japan. We evaluated the utility of our prediction rule modified estimation of physiologic ability and surgical stress (mE-PASS) in predicting postoperative adverse events in patients with choledochocystolithiasis. METHODS: A total of 4,329 patients who underwent elective surgery for choledochocystolithiasis in 44 referral hospitals between April 1987 and April 2007 were analyzed for mE-PASS along with postoperative events. The discrimination power of mE-PASS was assessed by the area under the receiver operating characteristic curve (AUC). The correlation between ordinal and interval variables was quantified by the Spearman rank correlation (ρ). The ratio of observed-to-estimated mortality rates (OE ratio) was used as a metric of surgical quality. RESULTS: Postoperative in-hospital mortality rates were 0 % (0/3,442) for laparoscopic cholecystectomy, 0.19 % (1/521) for open cholecystectomy, 1.6 % (1/63) for laparoscopic choledochotomy, 1.1 % (3/264) for open choledochotomy, and 5.1 % (2/39) for plasty or resection of the common bile duct. mE-PASS demonstrated a high discrimination power to predict in-hospital mortality; AUC, 95 % confidence interval (CI) of 0.96, 0.94-0.99. The predicted mortality rates significantly correlated with the severity of postoperative complications (ρ = 0.278, p < 0.0001) and length of hospital stay (ρ = 0.479, p < 0.0001). The OE ratios (95 % CI) improved slightly over time; 1.5 (0.25-9.0) between 1987 and 2000, and 0.40 (0.078-2.1) between 2001 and 2007. CONCLUSIONS: The present study suggests that mE-PASS can predict postoperative risks in patients who have undergone choledochocystolithiasis. mE-PASS may be useful in surgical decision making and evaluating the quality of care.

Prevalence and risk factors of bone metastasis and skeletal related events in patients with primary breast cancer in Japan.

BACKGROUND: Bone metastasis (BM) is important for studying systemic spread of breast cancer. It often causes skeletal-related events (SREs) that worsen quality of life. We investigated the prevalence and risk factors for BM and SRE using a dataset from the Breast Oncology Research Network (BORN) in Japan. PATIENTS AND METHODS: We collected data on primary breast cancer patients with node-positive or node-negative disease at intermediate to high risk of recurrence. The risk factors affecting the BM-free rate, SRE-free rate and overall survival were analyzed by using the Cox proportional hazard model. RESULTS: Data of 1,779 patients who were diagnosed with breast cancer during 2003-2005 were collected from the BORN and 1,708 cases were used for analysis. The median follow-up duration was 5.71 years. BM developed in 193 cases (11.3 %) and the BM-free rate at 5 years was 89.2 %. The annual hazard ratio of BM development differs remarkably according to the tumor subtype. SREs occurred in 133 (68.9 %) out of 193 patients and the SRE-free rate at 5 years was 92.6 %. In the multivariate analysis, clinical stage (P < 0.0001), number of lymph node (LN) metastases (P = 0.0029), tumor subtype (P = 0.034) and progesterone receptor status (P = 0.038) were independently significant risk factors for BM-free rate, but only clinical stage (P < 0.0001) and number of LN metastases (P = 0.0004) significantly correlated with SRE-free rate. CONCLUSIONS: This retrospective study clarifies the prevalence and risk factors for BM and SRE in Japanese breast cancer patients. Our results show the importance of considering subtype in the care of BM and SRE.

Value of general surgical risk models for predicting postoperative liver failure and mortality following liver surgery.

BACKGROUND AND OBJECTIVES: This study evaluated the ability of general surgical models to predict postoperative morbidity and mortality in liver surgery. METHODS: The postoperative course and mortality rates predicted by general surgical models were investigated in 960 patients who underwent hepatectomy or ablation therapy for primary or metastatic liver carcinoma. RESULTS: The area under the receiver operative characteristic curve (95% confidence intervals) for detecting postoperative liver failure was 0.89 (0.84-0.94), 0.85 (0.78-0.92), and 0.78 (0.72-0.85) for the estimation of physiologic ability and surgical stress (E-PASS) model, the modified E-PASS (mE-PASS) model, and the Portsmouth Physiologic and Operative Severity Score for the enUmeration of Mortality and morbidity (P-POSSUM) model, respectively, and those for detecting in-hospital mortality were 0.85 (0.76-0.93), 0.85 (0.78-0.92), and 0.79 (0.71-0.87), respectively. Nevertheless, all of the models overpredicted the overall mortality rate (by 2.3-fold for E-PASS, 2.3-fold for mE-PASS, and 2.9-fold for P-POSSUM). CONCLUSIONS: The general surgical risk models demonstrated high discriminatory power for predicting postoperative outcomes in liver surgery, but overpredicted the overall mortality rate by more than twofold. Therefore, these models should be refined to make them more suitable for predicting liver surgery outcomes.

Evaluation of modified Estimation of Physiologic Ability and Surgical Stress in gastric carcinoma surgery.

BACKGROUND: We recently modified our prediction scoring system "Estimation of Physiologic Ability and Surgical Stress" and have designated the current version mE-PASS. This scoring system has been designed to obtain predicted postoperative mortality rates before surgery and this study was performed to assess its usefulness in elective surgery for gastric carcinoma. METHODS: We investigated seven variables for mE-PASS and evaluated the postoperative course in 3,449 patients who underwent elective surgery for gastric carcinoma in Japan between August 20, 1987 and April 9, 2007, in order to quantify the predicted in-hospital mortality rates (R). The calibration and discrimination power of R were assessed using the Hosmer-Lemeshow test and the area under the receiver operating characteristic curve (AUC), respectively. The ratios of observed-to-estimated mortality rates (OE ratios) were quantified as a measure of quality. RESULTS: The overall postoperative morbidity and mortality rates were 19.0 and 2.0%, respectively. R demonstrated good power in calibration (χ(2) value, 12.5; df 8; P = 0.89) as well as discrimination (AUC, 95% confidence intervals: 0.80, 0.75-0.85). The OE ratios between hospitals ranged from 0.44 to 1.8. Overall, the OE ratios seemed to improve with time (OE ratio, 95% confidence intervals: 1.3, 0.73-2.4 for the early period between 1987 and 2000; 1.0, 0.59-1.7 for the middle period between 2001 and 2004; and 0.65, 0.36-1.2 for the late period between 2005 and 2007). CONCLUSION: Based on these findings, mE-PASS might be useful for medical decision-making and for assessing the quality of care in elective surgery for gastric carcinoma.

A multicenter prospective study of surgical audit systems.

OBJECTIVE: This study was undertaken to evaluate a modified form of Estimation of Physiologic Ability and Surgical Stress (E-PASS) for surgical audit comparing with other existing models. BACKGROUND: Although several scoring systems have been devised for surgical audit, no nation-wide survey has been performed yet. METHODS: We modified our previous E-PASS surgical audit system by computing the weights of 41 procedures, using data from 4925 patients who underwent elective digestive surgery, designated it as mE-PASS. Subsequently, a prospective cohort study was conducted in 43 national hospitals in Japan from April 1, 2005, to April 8, 2007. Variables for the E-PASS and American Society of Anesthesiologists (ASA) status-based model were collected for 5272 surgically treated patients. Of the 5272 patients, we also collected data for the Portsmouth modification of Physiologic and Operative Severity Score for the enUmeration of Mortality and morbidity (P-POSSUM) in 3128 patients. The area under the receiver operative characteristic curve (AUC) was used to evaluate discrimination performance to detect in-hospital mortality. The ratio of observed to estimated in-hospital mortality rates (OE ratio) was defined as a measure of quality. RESULTS: The numbers of variables required were 10 for E-PASS, 7 for mE-PASS, 20 for P-POSSUM, and 4 for the ASA status-based model. The AUC (95% confidence interval) values were 0.86 (0.79-0.93) for E-PASS, 0.86 (0.79-0.92) for mE-PASS, 0.81 (0.75-0.88) for P-POSSUM, and 0.73 (0.63-0.83) for the ASA status-based model. The OE ratios for mE-PASS among large-volume hospitals significantly correlated with those for E-PASS (R = 0.93, N = 9, P = 0.00026), P-POSSUM (R = 0.96, N = 6, P = 0.0021), and ASA status-based model (R = 0.83, N = 9, P = 0.0051). CONCLUSION: Because of its features of easy use, accuracy, and generalizability, mE-PASS is a candidate for a nation-wide survey.

Evaluation of modified estimation of physiologic ability and surgical stress in colorectal carcinoma surgery.

BACKGROUND: We recently modified Estimation of Physiologic Ability and Surgical Stress, our prediction scoring system. OBJECTIVE: This study evaluated the usefulness of our modified version for colorectal carcinoma in comparison with existing models. DESIGN: This investigation studied a multicenter cohort. SETTINGS: The study was conducted in regional referral hospitals in Japan. PATIENTS: Patients were included who underwent elective surgery for colorectal carcinoma. MAIN OUTCOME MEASURES: Postoperative morbidity, mortality, and predicted mortality rates for original and modified Estimation of Physiologic Ability and Surgical Stress were investigated in 2388 patients in comparison with existing European models. RESULTS: Among the models, the modified Estimation of Physiologic Ability and Surgical Stress demonstrated the highest discriminatory power in terms of in-hospital mortality (area under receiver operating characteristic curve: 0.84 for Estimation of Physiologic Ability and Surgical Stress, 0.87 for modified Estimation of Physiologic Ability and Surgical Stress, 0.84 for Portsmouth modification of POSSUM, 0.74 for ASA status-based model), as well as 30-day mortality (area under receiver operating characteristic curve: 0.82 for Estimation of Physiologic Ability and Surgical Stress, 0.84 for modified Estimation of Physiologic Ability and Surgical Stress, 0.81 for POSSUM, 0.78 for colorectal POSSUM, 0.76 for Association of Coloproctology of Great Britain and Ireland score). British models, in general, overpredicted postoperative mortality rates by more than 10 times. LIMITATIONS: The current study analyzed only the Japanese population treated in medium-volume centers. CONCLUSIONS: Among the models, modified Estimation of Physiologic Ability and Surgical Stress was the most accurate in predicting postoperative mortality in colorectal carcinoma surgery. These findings should be validated in Western populations, because the Japanese population may differ from Western populations in terms of body shape or reserve capacity.

Prediction of anastomotic leak and its prognosis in digestive surgery.

BACKGROUND: Anastomotic leak (AL) is a dangerous postoperative complication in gastrointestinal surgery. The present study focuses on whether our prediction scoring system, "Estimation of Physiologic Ability and Surgical Stress" (E-PASS), could predict occurrence of AL and its prognosis in various kinds of gastrointestinal surgical procedures. METHODS: We prospectively investigated parameters of E-PASS, absence or presence of AL, and in-hospital mortality in 6,005 patients who underwent elective digestive surgery with alimentary tract reconstruction in 45 acute care hospitals in Japan between 1 April 2002 and 31 March 2007. RESULTS: Incidences of AL were 19.6% for esophagectomy via right thoracotomy and laparotomy, 11.7% for pancreaticoduodenectomy, 7.4% for low anterior resection, 4.0% for total gastrectomy, 1.8% for open distal gastrectomy, 1.3% for open colectomy, for an overall incidence of 4.1%. The incidence in each procedure significantly correlated with median value of surgical stress score of the E-PASS (R = 0.78, n = 11, p = 0.0048). The incidences of AL increased when Total Risk Points (TRP) of the E-PASS increased; 1.1% at the TRP range of <500, 2.8% at 500 to <1,000, 4.8% at 1,000 to <1,500, and 13.6% at ≥ 1,500 (p < 0.0001). In patients who suffered from AL, an in-hospital mortality rate at TRP < 1,000 was significantly lower than that at TRP of ≥ 1,000 (1.1 vs. 15.9%; p = 0.00019). CONCLUSIONS: The E-PASS, requiring only nine variables, may be useful in predicting AL and its prognosis.

Probing Surface Morphology using X-ray Grating Interferometry.

X-ray reflectometry (XRR), a surface-sensitive technique widely used for characterizing surfaces, buried interfaces, thin films, and multilayers, enables determination of the electron density distribution perpendicular to a well-defined surface specularly reflecting X-rays. However, the electron density distribution parallel to the surface cannot be determined from an X-ray reflectivity curve. The electron density correlation in the lateral direction is usually probed by measuring the grazing-incidence small-angle X-ray scattering (GISAXS). GISAXS measurement, however, typically requires using a collimated X-ray point beam to distinguish the GISAXS from the specularly reflected X-rays, and so the sample must be scanned in the lateral direction with the point beam to investigate variations in the surface and interface morphology for a region larger than the size of the beam. In this paper, we report a new approach based on X-ray grating interferometry: an X-ray sheet beam is used instead of an X-ray point beam. A method using this approach can simultaneously provide one-dimensional real-space images of X-ray reflectivity, surface curvature, and 'dark-field' contrast with a field-of-view of more than a few millimetres. As a demonstration, a sample having a 400 nm line and space SiO2 pattern with a depth of 10 nm on its surface was used, and the dark-field contrast due to the unresolved line and space structure, creating GISAXS in the lateral direction, was successfully observed. Quantitative analysis of these contrasts provided the real-space distribution of the structural parameters for a simple model of the grating structure. Our study paves the way to a new approach to structure analysis, providing a quantitative way to investigate real-space variations in surface and interface morphology through wavefront analysis.

Laparoscopic transhiatal lymphadenectomy in the lower mediastinum for adenocarcinoma of the esophagogastric junction.

Laparoscopic transhiatal esophagogastrectomy is difficult because the lower mediastinum is so deeply located that the operative field is narrow and restricted by surrounding organs. Therefore, we performed lymphadenectomy with opening of the bilateral mediastinal pleura to maintain safety and obtain better exposure of lymph nodes and important organs. We will present our technique for laparoscopic lower mediastinal lymphadenectomy and reconstruction for cancer of the esophagogastric junction. Five abdominal ports were used. Retraction of the left lobe of the liver exposed the esophageal hiatus. A long, narrow gastric tube (3 cm wide) was formed, and regional abdominal lymph nodes (No. 1, 2, 3a, 7, 8a, 9, 19, and 20) were resected. The diaphragmatic hiatus was widely split and the opened bilateral mediastinal pleura enabled better exposure for lymph node dissection and reconstruction. The level where the inferior vena cava passed through the diaphragm into the chest was used as a landmark to identify supradiaphragmatic (No. 111) and lower thoracic paraesophageal nodes (No. 110), which were completely retrieved with this procedure. The posterior mediastinal nodes (No. 112pulR, 112pulL, and 112aoA) were also retrieved with bilateral opening of the mediastinal pleura and dissection of the inferior pulmonary ligaments. An esophagogastric tube anastomosis with pseudo-fornix was made with a no-knife linear stapler to prevent postoperative reflux esophagitis. This approach enabled safe and accurate laparoscopic lower mediastinal nodal dissection. With the advantage of a narrow gastric tube, the good working space made tension-free anastomosis possible.

[A phase II study of weekly paclitaxel for advanced or recurrent breast cancer].

The present study investigated the efficacy and safety of weekly administration of paclitaxel (PTX) for 37 patients with advanced or recurrent breast cancer. PTX was administered at a dose of 60 mg/m(2), 6 times every 8 weeks. The mean number of treatment cycles was 2.1, and the mean number of administrations was 12.7. Response rate was 35.1%. Two patients achieved CR, 11 PR, 13 NC (3 patients of long NC), 9 PD, and 2 NE. The clinical benefit rate (CR+PR+NC) was 70.3%. Median survival time was 733 days, and median time to treatment failure was 151 days. Grade 3 or more leucopenia and neutropenia occurred in 3 of patients (8.1%), and no patients showed hypersensitivity reaction after administration of PTX. Weekly PTX (60 mg/m(2)) is one of the treatment options in advanced or recurrent breast cancer from the standpoint of palliation.

High efficiency electrochemical immuno sensors using 3D comb electrodes.

To realize highly sensitive electrochemical immunoassays, a micro-fabricated three-dimensional (3D) electrode was fabricated and applied to enzyme immuno assay based on production of a redox species. The dimensions of the electrodes are 10 microm in width and 30 microm in height, with 20 microm spacing in between, and the 30 pairs of anode and cathode electrodes made up a single sensor. This structure lead to enhancement of the electrochemical reaction, nearly 100% of trap ratio of redox species. It can be applied to highly sensitive enzyme immuno sensing based on p-aminophenylphosphate (PAPP). Applicability of this technique to the immuno assay for one of the clinical diagnostic marker proteins (alpha-fetoprotein; AFP) from 6 to 500 ng/mL was demonstrated.

Prospects for single-molecule information-processing devices for the next paradigm.

Present information technologies use semiconductor devices and magnetic/optical disks; however, they are all foreseen to face fundamental limitations within a decade. Therefore, superceding devices are required for the next paradigm of high-performance information technologies. The paper first describes architectures suitable for single-molecule information processing, in which it is claimed that the performance of information processing is higher if speed and element number product is larger in almost all known architectures. Thus, single-molecule information-processing devices should be the most appropriate approach for the next paradigm. Then, prospects for single-molecule devices suitable for future information-processing technologies are described. Four possible milestones for realizing the Peta/Exa-floating operations per second (FLOPS) personal molecular supercomputer are proposed. Current status and necessary technologies of the first milestone are described, and necessary technologies for the next three milestones are also discussed.

Estimation of surgical costs using a prediction scoring system: estimation of physiologic ability and surgical stress.

HYPOTHESIS: Our predictive scoring system, Estimation of Physiologic Ability and Surgical Stress, can estimate surgical costs. DESIGN: Multicenter cohort study for 1 year. SETTING: Six national hospitals in Japan. PATIENTS: A consecutive series of 929 patients who underwent elective gastrointestinal operations. MAIN OUTCOME MEASURES: The preoperative and the comprehensive risk scores of the Estimation of Physiologic Ability and Surgical Stress were determined preoperatively and immediately after the operation, respectively. Estimated costs were computed using the following equation: costs = US $10,160 + (US $13,470 x comprehensive risk score). Data on length of stay, costs for surgical admission, and severity of postoperative complications were collected at hospital discharge. RESULTS: The comprehensive risk score significantly correlated with the severity of the postoperative complications (Spearman rank correlation = 0.54, P<.001), the length of stay (Spearman rank correlation = 0.69, P<.001), and the costs (Spearman rank correlation = 0.72, P<.001). The ratio of real to estimated costs varied from 0.82 to 1.17 at the various ranges of the comprehensive risk score, resulting in 0.93 in the total 929 patients. This ratio varied from 0.71 to 1.12 among the hospitals, the smallest of which was attributed to the hospital that primarily used the clinical pathways. A significant increase in the costs was observed according to the preoperative risk score for open colectomy (P =.009) and distal gastrectomy (P =.002). When we simulated the hospital revenue where different payment rates were set according to the preoperative risk score, the revenue seemed to improve in the hospitals that treated more high-risk patients, compared with the fixed payment system. CONCLUSION: The Estimation of Physiologic Ability and Surgical Stress scoring system may be useful for estimating surgical costs, making a benchmark analysis, and determining the rate in a risk-based payment system.

Primary osteosarcoma of the breast.

We report a case of primary osteosarcoma of the breast, which is a rare histological type of all breast tumors. A 58-year-old woman had noticed a right breast mass long before presenting to our hospital because it had gradually increased in size. The mass was bony-hard, 90 x 70 mm in size, and was located mainly in the upper outer quadrant of the left breast. Mammography demonstrated a round radiopaque mass with a shaggy outline. There were small bone metastases to the pelvis and scapula on bone radionuclide scan, but no other metastasis was observed with subsequent investigations. Modified radical mastectomy including axillary lymph node dissection was performed. Histologically, the excised tumor was consistent with extraskeletal osteosarcoma of the breast accompanied by lymph node metastses. In spite of adjuvant chemotherapy, the patient suffered a local recurrence four months later and died of aggressive multiple metastases 7 months after surgery.

[Three cases of advanced gastric cancer treated by TS-1 in combination with low-dose cisplatinum].

TS-1, a DPD inhibitory fluoropyrimidine, is a novel oral formation of 5-fluorouracil (5-FU). In patients with advanced gastric cancer, the response rate was reportedly over 40%. We report three cases of advanced gastric cancer treated using TS-1 in combination with a low-dose of cisplatinum (CDDP) that well responded. Case 1: A 62-year-old women underwent total gastrectomy. Ten weeks later, she suffered intestinal obstruction due to peritoneal recurrence of gastric cancer. Eighty mg of TS-1 in combination with bi-weekly administration of CDDP (10 mg) improved her intestinal obstruction. Case 2: A 50-year-old man suffered peritoneal recurrence of gastric cancer. Computed tomography (CT) showed intestinal obstruction, ascites, and hydronephrosis. After 100 mg of TS-1 in combination with bi-weekly administration of CDDP (20 mg) for 1 year, CT showed almost complete improvement of peritonitis carcinomatosa. Case 3: A 58-year-old man, who suffered advanced gastric cancer with peritonitis carcinomatosa, was administrated 100 mg of TS-1 in combination with bi-weekly administration of CDDP (20 mg). After 2 months of administration, remarkable improvement was observed in the upper gastrointestinal series. Adverse reactions, which were grade 1 for stomatitis, were observed only in case 1. All three patients are alive (case 1 and 2 have survived more than one year) and therapy is continuing. In conclusion, combined chemotherapy of TS-1 and low-dose CDDP was effective and well tolerable for advanced gastric cancer patients. It was suggested that effective biochemical modulation might be achieved by these two drugs.

Value of general surgical risk models for predicting postoperative morbidity and mortality in pancreatic resections for pancreatobiliary carcinomas.

BACKGROUND: The present study evaluated the utility of general surgical risk models to predict postoperative morbidity and mortality in the specialty field of pancreatic resections for pancreatobiliary carcinomas. METHODS: We investigated Estimation of Physiologic Ability and Surgical Stress (E-PASS), its modified version (mE-PASS), and Portsmouth Physiologic and Operative Severity Score for the enUmeration of Mortality and morbidity (P-POSSUM) in 231 patients undergoing pancreatoduodenectomy or distal pancreatectomy (Group A). We also analyzed E-PASS and mE-PASS in another cohort of the same procedures (Group B, n = 313). RESULTS: Areas under the receiver operating characteristic curve (AUC) for detecting in-hospital mortality in Group A were moderate at 0.75 for E-PASS, 0.69 for mE-PASS, and 0.69 for P-POSSUM. The predicted mortality rates of the models significantly correlated with severity of postoperative complications (ρ = 0.17, P = 0.011 for E-PASS; ρ = 0.15, and P = 0.027 for P-POSSUM). The AUCs were also moderate in Group B at 0.68 for E-PASS and 0.69 for mE-PASS. The predicted mortality rates significantly correlated with severity of postoperative complications (ρ = 0.18, P = 0.0018 for E-PASS; ρ = 0.17, and P = 0.0022 for mE-PASS). CONCLUSIONS: The present study suggests that the predictive powers of general risk models may be moderate in pancreatic resections. A novel model would be desirable for these procedures.