Scoring system for diagnosis and pretreatment risk assessment of neuroblastoma using urinary biomarker combinations.

The urinary catecholamine metabolites, homovanillic acid (HVA) and vanillylmandelic acid (VMA), are used for the adjunctive diagnosis of neuroblastomas. We aimed to develop a scoring system for the diagnosis and pretreatment risk assessment of neuroblastoma, incorporating age and other urinary catecholamine metabolite combinations. Urine samples from 227 controls (227 samples) and 68 patients with neuroblastoma (228 samples) were evaluated. First, the catecholamine metabolites vanillactic acid (VLA) and 3-methoxytyramine sulfate (MTS) were identified as urinary marker candidates through comprehensive analysis using liquid chromatography-mass spectrometry. The concentrations of these marker candidates and conventional markers were then compared among controls, patients, and numerous risk groups to develop a scoring system. Participants were classified into four groups: control, low risk, intermediate risk, and high risk, and the proportional odds model was fitted using the L2-penalized maximum likelihood method, incorporating age on a monthly scale for adjustment. This scoring model using the novel urine catecholamine metabolite combinations, VLA and MTS, had greater area under the curve values than the model using HVA and VMA for diagnosis (0.978 vs. 0.964), pretreatment risk assessment (low and intermediate risk vs. high risk: 0.866 vs. 0.724; low risk vs. intermediate and high risk: 0.871 vs. 0.680), and prognostic factors (MYCN status: 0.741 vs. 0.369, histology: 0.932 vs. 0.747). The new system also had greater accuracy in detecting missing high-risk neuroblastomas, and in predicting the pretreatment risk at the time of screening. The new scoring system employing VLA and MTS has the potential to replace the conventional adjunctive diagnostic method using HVA and VMA.

Impact of sclerosing dacryoadenitis/sialadenitis on relapse during steroid therapy in patients with type 1 autoimmune pancreatitis.

OBJECTIVES: Steroids are the first-line drugs for induction of remission in patients with type 1 autoimmune pancreatitis (AIP), and the usefulness of steroid maintenance therapy to prevent relapse has recently been reported. However, even during steroid therapy, a relatively large percentage of patients relapse and the predictive factors for relapse have not yet been elucidated. The aim of this study was to clarify the predictive factors for relapse of AIP patients during steroid therapy. MATERIALS AND METHODS: The medical records of 76 patients with type 1 AIP with continued steroid therapy after induction of remission were analyzed retrospectively. The relapse rate during steroid therapy was evaluated, and the risk factors for relapse were investigated by univariate and multivariate analysis of clinical factors. RESULTS: Relapse occurred in 28.9% (22/76) of the patients. The cumulative relapse rates were 10.5% at 1 year, 25.0% at 3 years, 34.9% at 5 years, and 43.0% at 10 years. In multivariate analysis, presence of sclerosing dacryoadenitis/sialadenitis at the time of initial diagnosis of AIP was an independent risk factor for relapse (HR 3.475, p = .009). The cumulative relapse rates of patients with sclerosing dacryoadenitis/sialadenitis reached 21.4% at 1 year, 56.0% at 3 years, and 78.0% at 5 years. CONCLUSIONS: Sclerosing dacryoadenitis/sialadenitis was a predictive factor for relapse in type 1 AIP during steroid therapy; in such cases, strict follow-up is necessary with relapse in mind.

Estimation of lung tumor position from multiple anatomical features on 4D-CT using multiple regression analysis.

To estimate the lung tumor position from multiple anatomical features on four-dimensional computed tomography (4D-CT) data sets using single regression analysis (SRA) and multiple regression analysis (MRA) approach and evaluate an impact of the approach on internal target volume (ITV) for stereotactic body radiotherapy (SBRT) of the lung. Eleven consecutive lung cancer patients (12 cases) underwent 4D-CT scanning. The three-dimensional (3D) lung tumor motion exceeded 5 mm. The 3D tumor position and anatomical features, including lung volume, diaphragm, abdominal wall, and chest wall positions, were measured on 4D-CT images. The tumor position was estimated by SRA using each anatomical feature and MRA using all anatomical features. The difference between the actual and estimated tumor positions was defined as the root-mean-square error (RMSE). A standard partial regression coefficient for the MRA was evaluated. The 3D lung tumor position showed a high correlation with the lung volume (R = 0.92 ± 0.10). Additionally, ITVs derived from SRA and MRA approaches were compared with ITV derived from contouring gross tumor volumes on all 10 phases of the 4D-CT (conventional ITV). The RMSE of the SRA was within 3.7 mm in all directions. Also, the RMSE of the MRA was within 1.6 mm in all directions. The standard partial regression coefficient for the lung volume was the largest and had the most influence on the estimated tumor position. Compared with conventional ITV, average percentage decrease of ITV were 31.9% and 38.3% using SRA and MRA approaches, respectively. The estimation accuracy of lung tumor position was improved by the MRA approach, which provided smaller ITV than conventional ITV.

A comparison of 4-Fr with 5-Fr endoscopic nasopancreatic drainage catheters: A randomized, controlled trial.

BACKGROUND AND AIM: Although endoscopic nasopancreatic drainage (ENPD) is useful for collecting samples for pancreatic juice cytology and for treating leakage of pancreatic juice and occlusive pancreatitis, placement of the ENPD catheter is associated with complications such as post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). We investigated whether an ENPD catheter with a smaller diameter could reduce the incidence of complications. METHODS: Patients requiring placement of an ENPD catheter (n = 254) were enrolled and randomly assigned to one of two catheter-size groups: the 4-Fr group or the 5-Fr group. The incidence of PEP, cholangitis, and spontaneous catheter displacement and the suitability of pancreatic juice cytology samples were compared between groups. In addition, univariate and multivariate analyses were conducted on factors associated with PEP. RESULTS: The incidence of PEP was significantly lower in the 4-Fr group compared with the 5-Fr group (4.1% vs 12.4%, respectively; P = 0.021). The rate of cholangitis and spontaneous catheter displacement and the suitability of pancreatic juice cytology samples did not differ between groups. Multivariate analysis revealed that the risk of PEP was 3.7 times higher when using a 5-Fr catheter than when using a 4-Fr catheter (P = 0.019). In addition, the risk of PEP was 4.1 times higher in patients with an intraductal papillary mucinous neoplasm than in those without (P = 0.0049) and 4.6 times higher in patients aged <65 than in those aged ≥65 (P = 0.0033). CONCLUSIONS: A 4-Fr catheter is as useful as a 5-Fr catheter and is associated with a significantly lower incidence of PEP.

Difference in dose-volumetric data between the analytical anisotropic algorithm, the dose-to-medium, and the dose-to-water reporting modes of the Acuros XB for lung stereotactic body radiation therapy.

The purpose of this study was to evaluate the difference in dose-volumetric data between the analytical anisotropic algorithms (AAA) and the two dose reporting modes of the Acuros XB, namely, the dose to water (AXB_Dw) and dose to medium (AXB_Dm) in lung stereotactic body radiotherapy (SBRT). Thirty-eight plans were generated using the AXB_Dm in Eclipse Treatment Planning System (TPS) and then recalculated with the AXB_Dw and AAA, using identical beam setup. A dose of 50 Gy in 4 fractions was prescribed to the isocenter and the planning target volume (PTV) D95%. The isocenter was always inside the PTV. The following dose-volumetric parameters were evaluated; D2%, D50%, D95%, and D98% for the internal target volume (ITV) and the PTV. Two-tailed paired Student's t-tests determined the statistical significance. Although for most of the parameters evaluated, the mean differences observed between the AAA, AXB_Dm, and AXB_Dw were statistically significant (p < 0.05), absolute differences were rather small, in general less than 5% points. The maximum mean difference was observed in the ITV D50% between the AXB_Dm and the AAA and was 1.7% points under the isocenter prescription and 3.3% points under the D95 prescription. AXB_Dm produced higher values than AXB_Dw with differences ranging from 0.4 to 1.1% points under isocenter prescription and 0.0 to 0.7% points under the PTV D95% prescription. The differences observed under the PTV D95% prescription were larger compared to those observed for the isocenter prescription between AXB_Dm and AAA, AXB_Dm and AXB_Dw, and AXB_Dw and AAA. Although statistically significant, the mean differences between the three algorithms are within 3.3% points.

Evaluation of antibiotic use to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis and cholangitis.

BACKGROUND/AIMS: The purpose of this study was to evaluate the relationship between prophylactic antibiotic use and complications following endoscopic retrograde cholangiopancreatography (ERCP). METHODOLOGY: We retrospectively evaluated 605 consecutive patients who underwent ERCP in our hospital between September 2009 and November 2011. The antibiotic group included patients who underwent their procedure before October 2010, while the control group included patients after October 1, 2010, who did not receive antibiotics. We compared the incidence of postoperative pancreatitis and cholangitis between the groups. RESULTS: There were no significant differences in the backgrounds of the 304 control and the 301 antibiotic-treated patients. The incidence of post-ERCP pancreatitis was 4.9% in the control group and 4.3% in the antibiotic group (p = 0.72). The incidence of postoperative cholangitis was 2.0% in the control group and 1.7% in the antibiotic group (p = 0.99). Choledocholithiasis, pancreatic duct injection, and female gender were detected as significant risk factors for postoperative pancreatitis by multivariate analysis; sclerosing cholangitis and incomplete biliary drainage were significant risk factors for postoperative cholangitis. Even in cases with these risk factors, prophylactic antibiotic use did not influence the incidence of pancreatitis or cholangitis. CONCLUSION: Prophylactic antibiotics do not reduce the incidence of either pancreatitis or cholangitis following ERCP.

Timing of radiological improvement after steroid therapy in patients with autoimmune pancreatitis.

OBJECTIVE: We retrospectively studied the timing of radiological improvement after steroid therapy in patients with autoimmune pancreatitis (AIP). MATERIAL AND METHODS: Patients with AIP (n = 31) received steroids followed by diagnostic imaging within 1 month. Pancreatic swelling, pancreatic and bile duct features, and apparent diffusion coefficient (ADC) were compared before and after treatment. The period from treatment initiation to evaluation was divided into five phases: early phase (days 3-5), week 1 (days 6 and 7), week 2 (days 8-14), week 3 (days 15-21), and week 4 (days 22-28). Five gastroenterologists evaluated pancreatic swelling and duct features (good/intermediate/no response), and the "good response" rate (response rate) was calculated for each phase. In addition, pancreatic volumes were measured with a 3D workstation before and after treatment, and the percentage change in volume was calculated. ADC values were calculated in 14 patients. RESULTS: The median ratio of pancreatic volume after relative to before treatment was 0.89, 0.79, 0.67, 0.59, and 0.47 for early phase, week 1, week 2, week 3, and week 4, respectively. The response rate of the pancreatic swelling was 37.5%, 57.1%, 83.3%, 100%, and 100%; response rate of the pancreatic duct was 0%, 20%, 75%, 75% and 100%; and response rate of the bile duct was 0%, 66.7%, 83.3%, 100%, and 80%. The ADC increased after treatment in all 14 patients, including the 7 patients evaluated in the early phase. CONCLUSIONS: Evaluation of pancreatic swelling and duct features is recommended in week 2 and thereafter. The ADC increased soon after treatment initiation, suggesting its usefulness for evaluating early treatment responses.

Comparative study of 4 Fr versus 6 Fr nasobiliary drainage catheters: a randomized, controlled trial.

BACKGROUND AND AIM: Despite the benefits of endoscopic nasobiliary drainage (NBD) in endoscopic retrograde cholangiopancreatography (ERCP), post-ERCP pancreatitis (PEP) and nose/throat discomfort can result. We aimed to determine whether the use of a smaller catheter alleviates these complications. METHOD: A randomized, controlled trial at a tertiary care center compared 4 Fr and 6 Fr NBD catheters; 165 ERCP patients with naïve papillae were randomly assigned to a catheter-size group. RESULTS: The prevalence of PEP was significantly lower in the 4 Fr group (3.7%; 3/82) than in the 6 Fr group (15.7%; 13/83; P = 0.019). No spontaneous catheter displacement occurred within 24 h. Discomfort visual analog scores were 2.6 and 4.3 in the 4 Fr and 6 Fr groups, respectively (P = 0.0048) on procedure day; on the following day, the scores were 2.3 and 3.6 (P = 0.028). Bile output was 16.3 mL/h and 21.4 mL/h in the 4 Fr and 6 Fr groups (P = 0.051). On obstructive jaundice subgroup analysis, bile drainage was 19.2 mL/h and 22.1 mL/h in the 4 Fr and 6 Fr groups (P = 0.40). The 4 Fr group required 5.6 days to reduce bilirubin levels versus 6.1 days in the 6 Fr group (P = 0.51). CONCLUSIONS: In patients with naïve papillae, lower rates of PEP and less nose/throat discomfort are associated with the use of 4 Fr NBD catheters. In patients with obstructive jaundice, 4 Fr and 6 Fr catheters are comparable with regard to bile output and bilirubin level reduction.

Characteristic Features of Cholangiocarcinoma Complicating Primary Sclerosing Cholangitis.

BACKGROUND/AIMS: Primary sclerosing cholangitis (PSC) is often complicated by cholangiocarcinoma (CCA); thus, early detection of CCA is an important way to improve PSC prognosis. METHODOLOGY: In a retrospective study, 23 cases of PSC were included. Seven cases were complicated by CCA (CCA group) and 16 cases were not (control group). Blood examinations, bile duct imagings from direct cholangiography, intraductal ultrasonography (IDUS) findings and pathological diagnosis results (bile juice cytology, brush cytology, and forceps biopsy) were referenced. RESULTS: Blood examinations showed that serum carbohydrate antigen 19-9 (CA19-9), total bilirubin, and aspartate aminotransferase were significantly higher in the CCA group, whereas cholangiography showed that the dominant stricture was significantly longer in the CCA group. No significant difference in the IDUS findings was observed between the 2 groups. Cholangioscopy enabled CCA diagnosis via identification of the papillary mucosa in sites other than the stricture. Forceps biopsy was the most useful pathological diagnostic technique, with a sensitivity of 86% and a specificity of 100%. CONCLUSIONS: The CA19-9 level and bile duct stricture morphology were useful for diagnosing CCA complicating PSC. Aggressive performance of cholangioscopy and pathological diagnostic techniques, such as brush cytology and forceps biopsy, are essential for identification.

The effect of respiratory-gated positron emission tomography/computed tomography in patients with pancreatic cancer.

Our aim of this study was to evaluate prospectively in patients with pancreatic cancer the effects of respiratory- gating during PET/CT acquisition on the determination of lesion volume and to measure tracer uptake. Our research included 36 patients diagnosed with pancreatic cancer. They underwent conventional whole-body PET/CT and subsequently respiratory-gated PET/CT of the upper abdomen. Based on list-mode PET acquisition data, respiratory-gated and non-gated images were created. Maximum standardized uptake values (SUVmax) and lesion volumes were compared between gated and non-gated images and also the rate of increase in SUVmax based on lesion size. Results showed that respiratory gating was successful in 34/36 patients. The median non-gated SUVmax was 6.2±2.1 and was 8.1±2.5 for respiratory- gated (P<0.01). Lesion volumes could be calculated in 27/34 patients. The median non-gated lesion volume was 5.82±5.57cm(3) and 4.31±4.56cm(3) for respiratory-gated (P<0.01). Furthermore, small lesions of ≤2cm had a significantly higher proportion of increased SUVmax compared to large lesions of >2cm (P=0.016). In conclusion, respiratory-gated PET/CT for patients with pancreatic cancer reduced respiratory motion artifacts and allowed significantly higher SUVmax to be obtained. In addition, the rate of increase in SUVmax tended to be higher in patients with pancreatic cancers of less or equal to 2cm diameter.

[Hepatic artery pseudoaneurysm after endoscopic biliary stenting for pancreatic cancer].

A man in his sixties presented to our hospital with obstructive jaundice and was diagnosed with inoperable pancreatic cancer. Chemoradiotherapy was initiated, and an expandable metallic stent was inserted endoscopically to drain the biliary system. Six months later, he was referred to our hospital with 1-week history of epigastric pain and obstructive jaundice. On admission for further evaluation, he experienced hematemesis and went into severe shock. Upper gastrointestinal endoscopy and endoscopic retrograde cholangiopancreatography showed active bleeding from the duodenal papilla. Therefore, we performed endoscopic nasobiliary drainage (ENBD). On day 4, blood was detected in the ENBD tube, and the patient again experienced hematemesis. Emergent enhanced computed tomography revealed a right hepatic arterial aneurysm that had likely ruptured and caused the hemobilia. The aneurysm was successfully embolized, and the patient was discharged on hospital day 21.

Clinical outcomes of scalp or face angiosarcoma treatment with intensity-modulated radiotherapy: a multicenter study.

Combined modality therapy, including radiotherapy (RT), is a common treatment for scalp or face angiosarcoma. Although intensity-modulated radiotherapy (IMRT) can deliver homogeneous doses to the scalp or face, clinical data are limited. This multicenter study aimed to evaluate scalp or face angiosarcoma treated with definitive or post-operative IMRT. We retrospectively analyzed data from patients who received IMRT for scalp or face angiosarcoma at three institutions between January 2015 and March 2020. Local control (LC) rate, overall survival (OS), progression-free survival (PFS), recurrence patterns and toxicity were evaluated. Fifteen patients underwent IMRT during the study period. Definitive RT was performed on 10 patients and post-operative RT was performed on 5 patients. The 1-year LC rate was 85.7% (95% confidence interval [CI], 53.9-96.2%). The 1-year OS and PFS rates were 66.7% (95% CI, 37.5-84.6%) and 53.3% (95% CI, 26.3%-74.4%), respectively. Univariate analysis revealed that a clinical target volume over 500 cm3 was associated with poor LC. Distant metastasis was the most common recurrence pattern. All patients experienced Grade 2 or 3 radiation dermatitis, and five patients experienced grade ≥ 3 skin ulceration. One patient who underwent maintenance therapy with pazopanib developed Grade 5 skin ulceration. Fisher's exact test showed that post-operative RT was significantly associated with an increased risk of skin ulceration of grade ≥ 3. These results demonstrate that IMRT is a feasible and effective treatment for scalp or face angiosarcoma, although skin ulceration of grade ≥ 3 is a common adverse event in patients who receive post-operative RT.

[Malignant phyllodes tumor metastatic to the pancreas: a case report].

A woman in her 50s was admitted with obstructive jaundice due to a pancreatic mass. She had a history of a right breast phyllodes tumor treated with mastectomy 3 years previously. Diagnostic imaging (endoscopic ultrasonography (EUS), CT, and MRI) demonstrated a well-demarcated mass in the pancreatic head. EUS-FNA showed spindle shaped tumor cells. The pancreaticoduodenectomy specimen showed a malignant spindle cell tumor consistent with a metastatic malignant phyllodes tumor. In addition, immunohistochemical staining demonstrated that the staining pattern of pancreatic tumor was similar to that of the breast phyllodes tumor. Pancreatic metastases from breast phyllodes tumors have rarely been reported in the literature.

Postoperative Intensity-Modulated Radiation Therapy for Myoepithelial Carcinoma in the Parotid Gland.

Myoepithelial carcinoma (MC) is an extremely rare form of tumor, with no standard treatment established to date. Although several reports have discussed postoperative radiation therapy (PORT), few have applied intensity-modulated radiation therapy (IMRT), and none has described the dose and radiation field in detail. In this report, we describe a case of MC of the parotid gland that was treated with high-dose IMRT (70 Gy) after partial resection. The patient, a 61-year-old female, underwent excisional surgery and was diagnosed with MC arising from a pleomorphic adenoma (PA). Postoperative irradiation was administered as 70 Gy in 35 fractions of local radiation. The patient had cancer recurrence in the irradiated field. However, no serious adverse events associated with the radiation therapy have been confirmed, implying that postoperative high-dose radiation therapy may be safely administered via IMRT.

Radiation recall pneumonitis induced by nivolumab in a patient with renal cell carcinoma.

INTRODUCTION: A radiation recall reaction in previously irradiated lungs is known as radiation recall pneumonitis. We encountered a rare case of radiation recall pneumonitis induced by nivolumab 9 months after palliative radiotherapy to the ribs. CASE PRESENTATION: The patient was a 69-year-old woman with renal cell carcinoma. She had received various drugs and palliative irradiation, which was followed by nivolumab treatment, for renal cell carcinoma. Three days after the initial nivolumab administration, she presented with respiratory symptoms. On the basis of chest computed tomography findings, she was diagnosed with nivolumab-induced radiation recall pneumonitis and treated with prednisolone (1 mg/kg). The condition resolved rapidly, and chest computed tomography 4 months after nivolumab cessation revealed interval resolution of the lung consolidation and persistent tumor shrinkage. CONCLUSION: Physicians should consider the risk of radiation recall pneumonitis during treatment with immune checkpoint inhibitors in patients who have received previous thoracic radiotherapy.

Use of 4-Fr versus 6-Fr Nasobiliary Catheter for Biliary Drainage: A Prospective, Multicenter, Randomized, Controlled Study.

Background and Aim. Endoscopic nasobiliary drainage (NBD) effects according to diameter remain unclear. We aimed to assess the drainage effects of the 4-Fr and 6-Fr NBD catheters. Methods. This prospective, multicenter, randomized, controlled study was conducted at Hiroshima University Hospital and related facilities within Hiroshima Prefecture. Endoscopic retrograde cholangiopancreatography (ERCP) in 246 patients revealed acute cholangitis, obstructive jaundice, and/or extrahepatic cholestasis; 4-Fr or 6-Fr NBD catheters were randomly allocated and placed in these patients. The primary endpoint was the efficacy of NBD based on the technical success rate and clinical success (rates of change in blood test and amount of bile output). Secondary endpoints included the spontaneous catheter displacement rate and nasal discomfort. Results. The technical success rate and clinical success did not differ significantly between groups. No spontaneous catheter displacement was noted in either group. Nasal discomfort due to catheter placement was significantly lower in the 4-Fr group versus the 6-Fr group (24 h after ERCP: 2.4 versus 3.5 cm, P = 0.005; 48 h after ERCP: 2.2 versus 3.1 cm, P = 0.01). Conclusion. The 4-Fr NBD catheter was not inferior to 6-Fr NBD catheter in terms of clinical success; the 4-Fr NBD catheter was useful to reduce nasal discomfort.

Endoscopic Modified Medial Maxillectomy for Resection of an Inverted Papilloma Originating from the Entire Circumference of the Maxillary Sinus.

For treatment of a sinonasal inverted papilloma (IP), it is essential to have a definite diagnosis, to identify its origin by computed tomography (CT) and magnetic resonance imaging (MRI), and to select the appropriate surgical approach based on the staging system proposed by Krouse. Recently, a new surgical approach named endoscopic modified medial maxillectomy (EMMM) was proposed. This approach can preserve the inferior turbinate and nasolacrimal duct. We successfully treated sinonasal IP with EMMM in a 71-year-old female patient. In this patient, the sinonasal IP originated from the entire circumference of the maxillary sinus. EMMM is not a difficult procedure and provides good visibility of the operative field. Lacrimation and empty nose syndrome do not occur postoperatively as the nasolacrimal duct and inferior turbinate are preserved. EMMM is considered to be a very favorable approach for treatment of sinonasal IP.

[Clinical benefit of bronchial arterial infusion chemotherapy to pulmonary metastasis from colorectal cancer--report of two cases].

Case 1: A 60-year-old woman with sigmoid colon cancer and multiple lung metastases developed dyspnea 34 months after sigmoidectomy and following systemic chemotherapy. Chest X-ray revealed left atelectasis and obstruction of the left main bronchus by lung metastasis, and stenosis of the right main bronchus was also suspected. Bronchial arterial infusion of CDDP, 5-FU and MMC relieved the atelectasis and dyspnea. The left bronchus remained patent for 12 months. Case 2: A 70-year-old man who had a pulmonary recurrence of rectal cancer suffered from hemoptysis and dyspnea, which had improved with systemic chemotherapy but then become exacerbated again. Bronchoscopic examination revealed intraluminal bleeding from a metastatic tumor. The symptoms were relieved after bronchial arterial infusion of CDDP, 5-FU and MMC. The diameter of the treated tumor was reduced by 15%. Hemoptysis was negligible until he died 8 months later. Bronchial arterial infusion chemotherapy for pulmonary metastasis from colorectal cancer is clinically beneficial, especially for patients with life-threatening respiratory symptoms like airway obstruction or intraluminal bleeding.

Antibiotic prophylaxis for endoscopic retrograde chlangiopancreatography increases the detection rate of drug-resistant bacteria in bile.

BACKGROUND: No consensus has yet been reached regarding the utility of antibiotic prophylaxis for endoscopic retrograde cholangiopancreatography (ERCP). However, there has been little discussion of potential adverse effects of antibiotic use. This study investigated the impact of antibiotic prophylaxis on overall levels of bacterial infiltration of the biliary tract and the prevalence of drug-resistance among that population. METHODS: Ninety-three patients, from whom intraoperative bile samples were collected after performing ERCP, were assigned to either an antibiotic-prophylaxis group (AP, n = 58) or a no-antibiotic-prophylaxis group (NAP, n = 35). Detection rates of biliary bacteria and antibiotic resistance were determined for each group. Multivariate analysis was also performed to identify risk factors for the development of drug-resistant biliary bacteria. RESULTS: The bile contamination rate was 37.1% for the NAP group and 55.2% for the AP group (P = 0.09). Drug-resistant bacteria were found in 5.7% of the NAP group and 29.3% of the AP group (P = 0.006). Biliary drainage and antibiotic prophylaxis for ERCP were identified as risk factors for the presence of drug-resistant bacteria. CONCLUSION: Administration of antibiotic prophylaxis prior to ERCP can be a risk factor for the selection of drug-resistant bacteria in the biliary tract.

Evaluation of different set-up error corrections on dose-volume metrics in prostate IMRT using CBCT images.

We investigated the effect of different set-up error corrections on dose-volume metrics in intensity-modulated radiotherapy (IMRT) for prostate cancer under different planning target volume (PTV) margin settings using cone-beam computed tomography (CBCT) images. A total of 30 consecutive patients who underwent IMRT for prostate cancer were retrospectively analysed, and 7-14 CBCT datasets were acquired per patient. Interfractional variations in dose-volume metrics were evaluated under six different set-up error corrections, including tattoo, bony anatomy, and four different target matching groups. Set-up errors were incorporated into planning the isocenter position, and dose distributions were recalculated on CBCT images. These processes were repeated under two different PTV margin settings. In the on-line bony anatomy matching groups, systematic error (∑) was 0.3 mm, 1.4 mm, and 0.3 mm in the left-right, anterior-posterior (AP), and superior-inferior directions, respectively. ∑ in three successive off-line target matchings was finally comparable with that in the on-line bony anatomy matching in the AP direction. Although doses to the rectum and bladder wall were reduced for a small PTV margin, averaged reductions in the volume receiving 100% of the prescription dose from planning were within 2.5% under all PTV margin settings for all correction groups, with the exception of the tattoo set-up error correction only (≥ 5.0%). Analysis of variance showed no significant difference between on-line bony anatomy matching and target matching. While variations between the planned and delivered doses were smallest when target matching was applied, the use of bony anatomy matching still ensured the planned doses.