Purpose: The use of two adjacent radiation beams to treat a lesion that is larger than the maximum field of a machine may lead to higher or lower dose distribution at the junction than expected. Therefore, evaluation of the junction dose is crucial for radiotherapy. Volumetric modulated arc therapy (VMAT) can effectively protect surrounding normal tissues by implementing a complex dose distribution; therefore, two adjacent VMAT fields can effectively treat large lesions. However, VMAT can lead to significant errors in the junction dose between fields if setup errors occur due to its highly complex dose distributions. Methods: In this study, setup errors of ±1, ±3, and ±5 mm were assumed during radiotherapy for treating large lesions in the lower abdomen, and their effects on the treatment dose distribution and target coverage were analyzed using gamma pass rate (GP) and homogeneity index (HI). All studies were performed using a computational simulation method based on our radiation treatment planning software. Results: Consequently, when the setup error was more than ±3 mm, most GP values using a 3%/3-mm criterion decreased by <90%. GP was independent of the direction of the field gap (FG), whereas HI values were relatively more affected by negative values for FG. Conclusions Therefore, the size and direction of setup errors should be carefully managed when performing dual-isocentric VMATs for large targets.

Purpose: The use of two adjacent radiation beams to treat a lesion that is larger than the maximum field of a machine may lead to higher or lower dose distribution at the junction than expected. Therefore, evaluation of the junction dose is crucial for radiotherapy. Volumetric modulated arc therapy (VMAT) can effectively protect surrounding normal tissues by implementing a complex dose distribution; therefore, two adjacent VMAT fields can effectively treat large lesions. However, VMAT can lead to significant errors in the junction dose between fields if setup errors occur due to its highly complex dose distributions. Methods: In this study, setup errors of ±1, ±3, and ±5 mm were assumed during radiotherapy for treating large lesions in the lower abdomen, and their effects on the treatment dose distribution and target coverage were analyzed using gamma pass rate (GP) and homogeneity index (HI). All studies were performed using a computational simulation method based on our radiation treatment planning software. Results: Consequently, when the setup error was more than ±3 mm, most GP values using a 3%/3-mm criterion decreased by <90%. GP was independent of the direction of the field gap (FG), whereas HI values were relatively more affected by negative values for FG. Conclusions Therefore, the size and direction of setup errors should be carefully managed when performing dual-isocentric VMATs for large targets.

Purpose: The use of two adjacent radiation beams to treat a lesion that is larger than the maximum field of a machine may lead to higher or lower dose distribution at the junction than expected. Therefore, evaluation of the junction dose is crucial for radiotherapy. Volumetric modulated arc therapy (VMAT) can effectively protect surrounding normal tissues by implementing a complex dose distribution; therefore, two adjacent VMAT fields can effectively treat large lesions. However, VMAT can lead to significant errors in the junction dose between fields if setup errors occur due to its highly complex dose distributions. Methods: In this study, setup errors of ±1, ±3, and ±5 mm were assumed during radiotherapy for treating large lesions in the lower abdomen, and their effects on the treatment dose distribution and target coverage were analyzed using gamma pass rate (GP) and homogeneity index (HI). All studies were performed using a computational simulation method based on our radiation treatment planning software. Results: Consequently, when the setup error was more than ±3 mm, most GP values using a 3%/3-mm criterion decreased by <90%. GP was independent of the direction of the field gap (FG), whereas HI values were relatively more affected by negative values for FG. Conclusions Therefore, the size and direction of setup errors should be carefully managed when performing dual-isocentric VMATs for large targets.

Purpose: The use of two adjacent radiation beams to treat a lesion that is larger than the maximum field of a machine may lead to higher or lower dose distribution at the junction than expected. Therefore, evaluation of the junction dose is crucial for radiotherapy. Volumetric modulated arc therapy (VMAT) can effectively protect surrounding normal tissues by implementing a complex dose distribution; therefore, two adjacent VMAT fields can effectively treat large lesions. However, VMAT can lead to significant errors in the junction dose between fields if setup errors occur due to its highly complex dose distributions. Methods: In this study, setup errors of ±1, ±3, and ±5 mm were assumed during radiotherapy for treating large lesions in the lower abdomen, and their effects on the treatment dose distribution and target coverage were analyzed using gamma pass rate (GP) and homogeneity index (HI). All studies were performed using a computational simulation method based on our radiation treatment planning software. Results: Consequently, when the setup error was more than ±3 mm, most GP values using a 3%/3-mm criterion decreased by <90%. GP was independent of the direction of the field gap (FG), whereas HI values were relatively more affected by negative values for FG. Conclusions Therefore, the size and direction of setup errors should be carefully managed when performing dual-isocentric VMATs for large targets.

Purpose: The use of two adjacent radiation beams to treat a lesion that is larger than the maximum field of a machine may lead to higher or lower dose distribution at the junction than expected. Therefore, evaluation of the junction dose is crucial for radiotherapy. Volumetric modulated arc therapy (VMAT) can effectively protect surrounding normal tissues by implementing a complex dose distribution; therefore, two adjacent VMAT fields can effectively treat large lesions. However, VMAT can lead to significant errors in the junction dose between fields if setup errors occur due to its highly complex dose distributions. Methods: In this study, setup errors of ±1, ±3, and ±5 mm were assumed during radiotherapy for treating large lesions in the lower abdomen, and their effects on the treatment dose distribution and target coverage were analyzed using gamma pass rate (GP) and homogeneity index (HI). All studies were performed using a computational simulation method based on our radiation treatment planning software. Results: Consequently, when the setup error was more than ±3 mm, most GP values using a 3%/3-mm criterion decreased by <90%. GP was independent of the direction of the field gap (FG), whereas HI values were relatively more affected by negative values for FG. Conclusions Therefore, the size and direction of setup errors should be carefully managed when performing dual-isocentric VMATs for large targets.

Objectives: Alcohol is metabolized to acetaldehyde by alcohol dehydrogenase enzyme in the liver and then acetaldehyde is metabolized to acetone by aldehyde dehydrogenase (ALDH) in the liver. There are two main ALDH enzymes which metabolize the acetaldehyde produced during ethanol oxidation. In particular, in the presence of the ALDH2 1*2 allele, the activity of the ALDH 2 enzyme is lowered. As a result, acetaldehyde metabolism is slowed down and acetaldehyde accumulates in the body compared to the ALDH2 1*1 allele. There are many studies that have investigated the blood acetaldehyde concentration according to the ALDH2 genotype, but there are few studies to compare this with age. So we investigated the blood acetaldehyde concentration according to ALDH2 genotype, age and gender. Methods: According to the ALDH2 genotype, we divided the group by gender and age. We divided the age group in to three groups which ranged from 20 to 34 years old, from 35 to 49 years old, and lastly from 50 to 64 years old. And then we collected blood samples after 15 min, 30 min, 1 hr, 2 hr, 3 hr, 4 hr, 5 hr and 15 hr of after drinking to measure the blood acetaldehyde concentration. Results: In ALDH2 1*2 allele group, there are significant differences of the blood acetaldehyde concentration between the age groups. In ALDH2 1*2 allele and male group, there are significant differences of the blood acetaldehyde concentration between the age groups. Conclusions There are significant differences of the blood acetaldehyde concentration between the age groups according to ALDH2 genotype. Also, there are significant differences of the blood acetaldehyde concentration between the age groups with male gender and ALDH2 1*2 allele. Studies about other factors that may influence the blood acetaldehyde concentration are needed.

Background/Aims: The ursodeoxycholic acid (UDCA) response score (URS) was developed to identify poor responders to UDCA before treatment, in order to offer timely and proactive intervention. However, validation of the URS in Asian population is warranted. Methods: A total of 173 Asian patients diagnosed with primary biliary cholangitis (PBC) between 2007 and 2016 at seven academic institutions in Korea who started UDCA treatment were analyzed to validate the performance of URS. UDCA response was defined as an alkaline phosphatase level less than 1.67 times the upper limit of normal after 1-year of UDCA treatment. In addition, prognostic performance of URS for liver-related events, defined as newly developed hepatic decompensation or hepatocellular carcinoma was evaluated. Results: After 1 year of UDCA treatment, 133 patients (76.9%) achieved UDCA response. UDCAresponse rate was 98.7% for those with URS ≥1.41 (n=76) and 58.8% for those with URS <1.41(n=97). The area under the receiver operating characteristic curve of URS in predicting UDCAresponse was 0.84 (95% confidence interval, 0.78 to 0.88). During a median follow-up of 6.5years, liver-related events developed in 18 patients (10.4%). Among 117 patients with PBC stage I-III by histological evaluation, the 5-year liver-related event-free survival rate differed accordingto the URS; 100% for URS ≥1.41 and 86.5% for URS <1.41 (p=0.005). Conclusions URS demonstrated good performance in predicting a UDCA treatment response in Asian PBC patients. In addition, the risk of liver-related events differed according to the URS for the PBC stage. Thus, URS can be used to predict the response and clinical outcome in patients with PBC.

Objectives: The effectiveness of drugs currently used in medication, which is important in the treatment of alcohol use disorders, is limited. Recently, ondansetron which acts as 5-HT3 receptor antagonist, has been studied and proved possibility as new medication for alcohol use disorder. Meanwhile, there are studies supporting that 5-HT1A receptors are related to addictive behavior. Considering those studies, we expect that vortioxetine, which acts as both 5-HT3 receptor antagonist and 5-HT1A receptor agonist, may be effective in treatment of alcohol use disorder. The purpose of this study is to examine the effect of vortioxetine on alcohol intake of C57BL/6 mice. Methods: In this study C57BL/6 mice were randomly assigned to normal saline group, vortioxetine 10 mg/kg group and vortioxetine 1 mg/kg group. To study effect of vortioxetine on alcohol, water, food intake and body weight of mice, we administered each medication for 14 days. Results: The overall alcohol intake was different between the three groups (PGroup=0.021), and alcohol intake in vortioxetine 10 mg/kg group was significantly lower than one in placebo group. Change across time points (PTime<0.001) and the interaction between group and time (PGroup×Time =0.016) were also significant. However, there were no significant differences between the three groups in water, food intake and body weight. Conclusions These results indicated that administration of high dose vortioxetine reduced alcohol intake of mice.Therefore, it is necessary to conduct clinical studies to examine the effectiveness of vortioxetine as a new treatment for alcohol use disorder.

Background/Aims: This study examined the long-term outcomes of undifferentiated-type early gastric cancer (UD EGC) with positive horizontal margins (HMs) after endoscopic resection (ER) and compared them between additional surgery and nonsurgical management. Methods: From 2005 to 2015, a total of 1,124 patients with UD EGC underwent ER at 18 tertiary hospitals in Korea. Of them, 92 patients with positive HMs as the only noncurative factor (n=25) or with both positive HMs and tumor size >2 cm (n=67) were included. These patients underwent additional surgery (n=40), underwent additional endoscopic treatment (n=6), or were followed up without further treatment (n=46). Results: No lymph node (LN) metastasis was found in patients who underwent additional surgery. During a median follow-up of 57.7 months (interquartile range, 27.6 to 68.8 months), no LN or distant metastases or gastric cancer-related deaths occurred in the overall cohort. At baseline, the residual cancer rate was 57.8% (26/45) after additional surgery or ER. The 5-year local recurrence rate was 33.6% among patients who were followed up without additional treatment. The 5-year overall survival rates were 95.0% and 87.8% after additional surgery and nonsurgical management (endoscopic treatment or close follow-up), respectively (log-rank p=0.224). In the multivariate Cox regression analysis, nonsurgical management was not associated with an increased risk of mortality. Conclusions UD EGC with positive HMs after ER may have favorable long-term outcomes and a very low risk of LN metastasis. Nonsurgical management may be suggested as an alternative, particularly for patients with old age or chronic illness.

Malakoplakia is a rare chronic granulomatous disease found in the genitourinary tract, mainly. It is considered to be related to immunosuppression and/or infectious processes. We would like to present an operative case of cecal malakoplakia in a patient with a history of surgical resection and chemotherapy for cervical cancer. A 74-year-old female patient visited our hospital for 1-year follow-up after operation and chemo-radiotherapy for cervical cancer. An infiltrative mass of 6 cm, between the cecal base and the right psoas muscle, was observed on computed tomography. An ileocectomy was performed for diagnosis. Histopathologic examination revealed cecal malakoplakia. After surgery, based on previous reports, antibiotics therapy was added. Then the patient was discharged and treated in the outpatient clinic. To our knowledge, a rare case has been described of cecal malakoplakia during observation after surgery and chemo-radiotherapy for cervical cancer. Malakoplakia is known to be related to immunosuppressive condition. Therefore, our case suggests that close observation should be made in patients on immunosuppressive condition, such as chemotherapy.