Dosimetric comparison of VitalBeam® and HalcyonTM 2.0 for hypofractionated VMAT with simultaneous integrated boost treatment of early-stage left-sided breast cancer.

PURPOSE: This study compared the quality of treatment plans for early-stage, left-sided breast cancer, as planned for and delivered by the HalcyonTM and VitalBeam® . MATERIALS AND METHODS: Fifteen patients diagnosed with early-stage left-sided breast cancer, who had received VMAT with hypofractionated SIB, were recruited. All cases were planned using HalcyonTM comprising a dual-layer MLC (DL-MLC) and VitalBeam® with a Millennium 120 MLC (VB-MLC). For the PTVs, the quality of coverage (QC), conformity index (CI), and homogeneity index (HI) were calculated for each plan. The dosimetric differences between the two treatment plans were statistically compared using the Wilcoxon signed-rank test (p < 0.05). To evaluate delivery efficiency, the average delivery time for each patient's treatment plan was recorded and compared. RESULTS: For the PTVs, the two plans (DL-MLC and VB-MLC) were comparable in terms of the QC, CI, and HI. However, V30Gy and Dmean for the heart in the DL-MLC plan were significantly reduced by 0.49% and 14.6%, respectively, compared with those in the VB-MLC plan (p < 0.05). The Dmean value for the ipsilateral lung in the DL-MLC plan significantly decreased by 5.5%, compared with that in the VB-MLC plan (p < 0.05). In addition, the delivery times for the DL-MLC and VB-MLC plans were 79 ± 10 and 101 ± 11 s, respectively. CONCLUSIONS: DL-MLC plans were found to improve OAR sparing. In particular, when treating left-sided breast cancer via DL-MLC plans, the risk of heart toxicity is expected to be reduced.

Incidence and risk factors for congestive heart failure in patients with early breast cancer who received anthracycline and/or trastuzumab: a big data analysis of the Korean Health Insurance Review and Assessment service database.

PURPOSE: We aimed to analyze the incidence, time to occurrence, and congestive heart failure (CHF) risk factors for early breast cancer patients treated with anthracycline (AC)-based chemotherapy and/or trastuzumab (T) therapy in Korea. METHODS: We included female patients > 19 years old from the Health Insurance Review and Assessment Service database who had no prior CHF history and had been diagnosed with early breast cancer between January 2007 and October 2016. RESULTS: We included 83,544 patients in our analysis. In terms of crude incidence for CHF, AC followed by T showed the highest incidence (6.3%). However, 3.1 and 4.2% of the patients had CHF due to AC-based chemotherapy and non-AC followed by T, respectively. The median times to occurrence of CHF were different according to adjuvant treatments, approximately 2 years (701.0 days) in the AC-based chemotherapy group vs 1 year (377.5 days) AC followed by T group. T therapy was associated with earlier development of CHF irrespective of previous chemotherapy, but late risk of CHF 1.2 years after T therapy rapidly decreased in both chemotherapy groups. Multivariate Cox regression analysis revealed that the adjusted hazard ratio for CHF was increased in the group of older patients (≥ 65 years old) who underwent AC followed by T therapy, with Charlson comorbidity index scores of ≥ 2. CONCLUSIONS: Our study showed that neo-/adjuvant chemotherapy using T irrespective of previous chemotherapy (AC or non-AC) was associated with significantly increased risk of CHF compared with AC-based chemotherapy in Korean patients with early breast cancer.

Factors predicting intolerance to definitive conventional radiotherapy in geriatric patients.

PURPOSE: Although radiotherapy can be administered with a relatively low therapeutic burden, many elderly patients do not complete radiotherapy. In order to predict intolerance during radiotherapy, this study retrospectively analyzed the frequency of and risk factors for radiotherapy interruption among geriatric patients. METHODS: From September 2009 to December 2016, 353 patients aged ≥70 years received definitive radiotherapy with a conventionally fractionated schedule. "Total interruption" included completion of ≤90% of a planned radiotherapy, temporary discontinuation, and treatment-related mortality within 2 months. "Early-phase incompletion" and "mid-phase incompletion" represented completion of ≤50 and ≤80% of a planned radiotherapy, respectively. RESULTS: The median age of patients was 74 years. Early- and mid-phase incompletions and total interruption occurred in 4.2, 9.3, and 19.3% of patients, respectively. Total interruption occurred frequently in cancers involving the thorax (27.4%), head and neck (23.1%), abdomen (20.0%), pelvis (17.4%), and breast/extremity (8.1%). The Eastern Cooperative Oncology Group (ECOG) performance score (P = 0.004 and 0.002), serum albumin level (P = 0.016 and 0.002), and the expected 5­year survival (P = 0.033 and 0.034) were significant factors for mid-phase incompletion and total interruption. Age ≥ 75 years (P = 0.008), concurrent chemotherapy (P = 0.017), and the extent of radiation field (P = 0.027) were factors associated with total interruption. CONCLUSION: Overall, 19.3% of the elderly patients showed treatment intolerance during conventional radiotherapy. Serum albumin level and ECOG performance score should be considered as surrogate markers for radiotherapy interruption prior to the decision regarding definite conventional radiotherapy.

A Survey of Radiation Therapy Utilization in Korea from 2010 to 2016: Focusing on Use of Intensity-Modulated Radiation Therapy.

BACKGROUND: This study aimed to assess the recent changes of radiation therapy (RT) modalities in Korea. In particular, we focused on intensity-modulated radiation therapy (IMRT) utilization as the main index, presenting the application status of advanced RT. METHODS: We collected information from the Korean Health and Insurance Review and Assessment Service data based on the National Health Insurance Service claims and reimbursements records by using treatment codes from 2010 to 2016. We classified locating region of each institution as capital vs. non-capital areas and metropolitan vs. non-metropolitan areas to assess the regional difference in IMRT utilization in Korea. RESULTS: IMRT use has been steadily increased in Korea, with an annual increase estimate (AIE) of 37.9% from 2011 to 2016 (P < 0.001) resulting in IMRT being the second most common RT modality following three-dimensional conformal radiotherapy. In general, an increasing trend of IMRT utilization was observed, regardless of the region. The rate of AIE in the capital areas or metropolitan areas was higher than that in non-capital areas or non-metropolitan areas (40.7% vs. 31.9%; P < 0.001 and 39.7% vs. 29.4%; P < 0.001, respectively). DISCUSSION: The result of our survey showed that IMRT has become one of the most common RT modalities. IMRT is becoming popular in both metropolitan and non-metropolitan areas, while metropolitan area has faster AIE possibly due to concentration of medical resources and movement of advanced patients.

The Role of Adjuvant Radiation Therapy for Locoregionally Advanced Papillary Thyroid Carcinoma.

OBJECTIVES: To investigate the role of adjuvant radiation therapy in locoregional control in patients with locoregionally advanced papillary thyroid carcinoma (pT4 or pN1b) based on a comparison of a group that received radiation therapy and a group that did not receive radiation therapy. METHODS: A retrospective analysis was performed on 165 patients with locoregionally advanced papillary thyroid carcinoma who underwent treatment between 2002 and 2011. Of these, 32 patients received adjuvant radiation therapy, and 133 patients did not receive radiation therapy. RESULTS: The median follow-up period was 7.2 years (range, 3.4-13.6) for the overall study population. The 10-year locoregional recurrence-free survival rates for patients in the radiation therapy and no radiation therapy groups were 83.9 and 60.8%, respectively (p = 0.037). The overall survival rate and distant recurrence-free survival rate were not different between the two groups (p = 0.076 and p = 0.813, respectively). Multivariate analysis showed that adjuvant radiation therapy was an independent prognostic factor for locoregional recurrence-free survival (p = 0.040). CONCLUSIONS: Adjuvant radiation therapy for patients with either pT4 or pN1b disease improved locoregional recurrence-free survival and might be of benefit for patients with these high-risk features by reducing the need for additional salvage treatment after locoregional recurrence.

Quantitative analysis of tumor volume reduction after three-dimensional conformal radiation therapy for intracranial meningiomas.

To provide radiobiological information on the inherent response of intracranial meningiomas after three-dimensional conformal radiation therapy. Quantitative tumor volume measurements were generated from 120 magnetic resonance images of a total of 24 patients. Gross tumor volumes were delineated on a series of contrast-enhanced T1-weighted magnetic resonance images by using commercial software. The percentage of tumor volume reduction at each follow-up was determined and compared to the baseline tumor volume. The median follow-up time was 103.5 months (range 30-137 months). The mean pre-radiation therapy tumor volume was 30.0 cm(3) (range 1.3-167.4 cm(3)). Tumor volume reduction was observed in 96 % of the study population. The mean absolute and relative tumor volume reduction were 14.0 cm(3) (range -0.6-84.5 cm(3)) and 40.8 % (range -6.8-82.9 %), respectively. The mean relative tumor volume reduction was 15.9, 28.9, 40.5, 50.3, and 52.6 % at 2, 4, 6, 8, and 10 years after irradiation. The quantitative volumetric analysis of the pattern of tumor volume reduction in response to irradiation gives an insight into the radiobiological nature of intracranial meningiomas after conventionally fractionated radiation therapy.

Intraoperative Radiation Therapy for Gallbladder Cancer: Experience at a Single Institution.

BACKGROUND/AIMS: To investigate the survival outcome of intraoperative radiation therapy for patients with gallbladder cancer on the basis of experience at a single institution. METHODOLOGY: The medical records of 8 patients with gallbladder cancer who were treated with intraoperative radiation therapy during surgical resection or palliative surgery were retrospectively analyzed. The primary endpoint was overall survival. The median follow-up time was 20.8 months. RESULTS: The median survival time was 15.0 months. Overall survival for all patients was 75.0% at 1 year, 37.5% at 3 years, and 25.0% at 5 years. Three patients underwent complete resection, and 5 patients had residual tumor after resection or palliative surgery. The 3-year OS rate for 3 patients with no residual tumor after curative resection was 66.7%, with a mean survival time of 122.6 months, whereas the 3-year OS rate for 5 patients with macroscopic residual diseasewas 0% with a mean survival time of 13.5 months (P = 0.014). CONCLUSIONS: The results of the present study suggest that intraoperative radiation therapy with or without external beam radiation therapy was safe and beneficial for patients who underwent curative resection with negative margins and allows the possibility of long-term survival.

Feasibility of fast, four-dimensional computed tomography-based O-ring LINAC plans for lung stereotactic body radiotherapy in patients with poor performance status.

Purpose: We aimed to retrospectively analyzed the feasibility of fast four-dimensional computed tomography (4DCT)-based O-ring LINAC treatment for patients with an average respiratory amplitude was< 0.5 cm and who cannot endure long treatment times due to poor performance status in lung 4D-stereotactic body radiotherapy (SBRT). Methods: This study included data of 38 patients who received lung 4D-SBRT and had average respiratory amplitude< 0.5 cm in the full phase. C-arm LINAC plans were based on 4DCT data obtained at phase values ranging from 20-70% using a C-arm LINAC. O-ring LINAC plans were retrospectively established based on 4DCT data obtained at phase values of 0-90% using an O-ring LINAC. The conformity index (CI), homogeneity index (HI), and gradient measurement of the planning target volumes (PTV) were analyzed to compare dosimetric data between C-arm LINAC and O-ring LINAC plans. Organs at risk were analyzed in accordance with the Radiation Therapy Oncology Group 0915 protocol. Treatment delivery time and total monitor units were analyzed to compare the efficiency of treatment delivery. Statistical comparisons were performed using the Wilcoxon signed-rank test (P< 0.05). Results: For the PTV, there was no significant difference in the CI or HI between C-arm LINAC and O-ring LINAC plans. For organs-at-risk, all plans met the criteria for dose constraint. There was a significant difference between C-arm LINAC and O-ring LINAC plans except in the spinal cord. Treatment delivery time was 92% longer for C-arm LINAC plans than for O-ring LINAC plans. The total MU value for C-arm LINAC plans was 9.6% higher than that for O-ring LINAC plans. Conclusion: We verified the feasibility of fast 4DCT-based O-ring LINAC treatment for patients with average respiratory amplitude< 0.5 cm and who cannot endure long treatment times due to poor performance status in lung 4D-SBRT.

Effectiveness of high-dose three-dimensional conformal radiotherapy in hepatocellular carcinoma with portal vein thrombosis.

OBJECTIVE: To evaluate the treatment outcome of three-dimensional conformal radiotherapy in hepatocellular carcinoma patients with portal vein thrombosis, concerning survival and treatment response of thrombosis. METHODS: Forty-five patients with hepatocellular carcinoma who had portal vein thrombosis treated from March 2005 to March 2011 were the subjects of this study. The median total dose was 61.2 Gy (range 38-65 Gy). A daily radiation dose of 1.8-2.5 Gy was administered at a frequency of five fractions per week. The clinical target volume included portal vein thrombosis with or without primary tumour with clinical consideration. RESULTS: Three of the 45 patients (6.7%) showed complete remission of portal vein thrombosis, 25 patients (55.6%) showed partial response, 14 patients (31%) had stable disease and 3 patients (6.7%) had progressive disease. The median and the 1-year survival rate of the responders (complete remission + progressive disease) were 16.7 months and 63.7%, respectively, and those of the non-responders were 8 months and 28.2%, respectively (P= 0.003). A univariate analysis revealed that thrombosis response, Eastern Cooperative Oncology Group performance status, maximum tumour size, tumour bilaterality, Cancer of the Liver Italian Program stage, Okuda stage, hepatic arterial infusion, hepatitis B 'e' antigen and hepatitis C antibody were statistically significant prognostic factors affecting survival. In a multivariate analysis, thrombosis response, Cancer of the Liver Italian Program stage and Okuda stage were found to be statistically significant. No clinically significant radiation-induced liver disease was noted. One grade 3 late complication (duodenal ulcer) was reported. CONCLUSIONS: High-dose three-dimensional conformal radiotherapy yielded a response rate of 62.3%. It is a safe and effective treatment prolonging the survival of hepatocellular carcinoma patients with portal vein thrombosis.

The extent and serial pattern of interfractional variation in patients with whole pelvic irradiation: a study using a kilovoltage orthogonal on-board imager.

The purpose of this study is to assess the extent and serial pattern of setup error of conventional fractionated whole pelvic irradiation using a kilovoltage on-board imager. The daily on-board images of 69 patients were matched with the digitally reconstructed radiographs of simulation on the basis of pelvic bony structure. The shifts along x- (lateral), y- (longitudinal), and z- (vertical) axes, and the 3D vector, were measured. The shift between an origin of the first fraction and each fraction (Δshift(1st)) and the shift between an isocenter of simulation and each fraction (Δshift(Sim)) were calculated. To evaluate serial changes, the shifts of each fraction were classified into four consecutive sessions, and an ANOVA and chi-square test were used. The systematic error of the Δshift(Sim) and Δshift(1st) were 2.72 and 1.43 mm along the x-axis, 2.98 and 1.28 mm along the y-axis, and 4.26 and 2.39 mm along the z-axis, respectively. The Δshift(Sim) and Δshift(1st) ≥ 5 mm of the 3D vector occurred in 54.3% and 23.1%, respectively. The recommended margins to cover setup error in case of using Δshift(1st) were 3.81, 3.54, and 6.01 mm along x-, y-, and z-axes, whereas those using Δshift(Sim) were 6.39, 6.95, and 9.95 mm, respectively. With the passage of time, the Δshift(1st) ≥ 5 mm of 3D vector and along any axis in supine setup increased from 14.1% for first session to 22.5% for fourth session (p=0.027) and from 10.8% to 18.5% (p = 0.034), respectively. In prone setup, first session was better than others in the Δshift(1st) ≥ 5 mm of 3D vector and along any axis. It is expected that the correction using the on-board images on the first fraction improves geometrical uncertainties and reduces the margin for target coverage. Daily continuous OBI follow-up during conventional fractionated pelvic irradiation can increase the reproducibility and be more effective in the late period.

Evaluation of mechanical accuracy for couch-based tracking system (CBTS).

This study evaluated the mechanical accuracy of an in-house-developed couch-based tracking system (CBTS) according to respiration data. The overall delay time of the CBTS was calculated, and the accuracy, reproducibility, and loading effect of the CBTS were evaluated according to the sinusoidal waveform and various respiratory motion data of real patients with and without a volunteer weighing 75kg. The root mean square (rms) error of the accuracy, the reproducibility, and the sagging measurements were calculated for the three axes (X, Y, and Z directions) of the CBTS. The overall delay time of the CBTS was 0.251 sec. The accuracy and reproducibility in the Z direction in real patient data were poor, as indicated by high rms errors. The results of the loading effect were within 1.0 mm in all directions. This novel CBTS has the potential for clinical application for tumor tracking in radiation therapy.

Protective effect of triphala on radiation induced acute intestinal mucosal damage in Sprague Dawley rats.

Aim of the study was to determine protective effect of triphala on radiation-induced rectal mucosal damage. Male Sprague Dawley rats (30) were divided into 5 groups. Rats in group A were sham irradiated and rats in group B underwent only irradiation. Rats in group C were administered triphala 1 g/kg/day orally for 5 consecutive days before irradiation. Rats in group D and E were administered triphala 1 and 1.5 g/kg/day orally for 10 consecutive days, respectively. Rectal mucosal damage was induced by a single fraction of 12.5Gy gamma irradiation (Ir-192) on 5th day. All the rats were autopsied on 11th day and histological changes in surface epithelium, glands, and lamina propria were assessed. Proctitis showed significant improvement in surface epithelium (P < 0.024), glands (P < 0.000) and lamina propria (P < 0.002) in group E compared to group B. Rats in group E showed significantly less change in glands (P < 0.000) compared to rats in group D, All histological variables (surface epithelium, P < 0.001; glands, P < 0.000; lamina propria, P < 0.003) compared to rats in group C. In a Tukey-b test, group E had a significantly recovered grade for glands (P < 0.000) compared to groups B, C and D. Results of the present study showed that high-dose triphala improved radiation-induced damage of glands.

Combined Therapy with microRNA-Expressing Salmonella and Irradiation in Melanoma.

Anticancer treatment strategies using bacteria as a vector are currently expanding with the development of anticancer drugs. Here, we present a research strategy to develop anticancer drugs using bacteria that contain miRNAs. We also present a strategy for the development of novel bacterial anticancer drugs in combination with radiation. Salmonella strains expressing miRNA were produced by modifying the miRNA expression vector encoding INHA, a radiation-resistant gene developed previously. The anticancer effect of INHA was confirmed using skin cancer cell lines. We also tested a combination strategy comprising bacteria and radiation for its anticancer efficacy against radiation-resistant mouse melanoma to increase the efficacy of radiation therapy as a novel strategy. The recombinant strain was confirmed to promote effective cell death even when combined with radiation therapy, which exerts its cytotoxicity by enhancing reactive oxygen species production. Moreover, a combination of bacterial and radiation therapy enhanced radiotherapy efficacy. When combined with radiation therapy, bacterial therapy exhibited effective anti-cancer properties even when administered to animals harboring radiation-resistant tumors. This strategy may promote the secretion of cytokines in cells and more effectively reduce the number of bacteria remaining in the animal. Thus, this study may lead to the development of a strategy to improve the effectiveness of radiation therapy using Salmonella expressing cancer-specific miRNA for intractable cancers such as those resistant to radiation.

Synchrotron Radiation-Based Refraction-Contrast Tomographic Images Using X-ray Dark-Field Imaging Optics in Human Lung Adenocarcinoma and Histologic Correlations.

The aim of this study was to evaluate the clinical implication of synchrotron radiation imaging techniques for human lung adenocarcinoma in comparison with pathologic examination. A refraction-based tomographic imaging technique called the X-ray dark-field imaging (XDFI) method was used to obtain computed tomographic images of human lung adenocarcinoma at the beam line at Photon Factory BL 14B at the High Energy Accelerator Research Organization (KEK) in Tsukuba, Japan. Images of normal lung tissue were also obtained using the same methods and reconstructed as 3D images. Both reconstructed images were compared with pathologic examinations from histologic slides which were made with identical samples. Pulmonary alveolar structure including terminal bronchioles, alveolar sacs, and vasculatures could be identified in synchrotron radiation images of normal lung. Hyperplasia of interstitial tissue and dysplasia of alveolar structures were noticed in images of lung adenocarcinoma. Both synchrotron radiation images were considerably correlated with images from histologic slides. Lepidic patterns of cancer tissue were distinguished from the invasive area in synchrotron radiation images of lung adenocarcinoma. Refraction-contrast tomographic techniques using synchrotron radiation could provide high-resolution images of lung adenocarcinoma which are compatible with those from pathologic examinations.

Practical effectiveness of re-irradiation with or without surgery for locoregional recurrence of rectal cancer: A meta-analysis and systematic review.

BACKGROUND AND PURPOSE: Re-irradiation might yield local control (LC) or palliation for locoregionally recurrent rectal cancer (LRRC), but iatrogenic complications are a possible hindrance. We aimed to evaluate the efficacy of re-irradiation to determine optimal treatment of LRRC. METHODS: We performed a systematic review of PubMed, MEDLINE, Cochrane Library, and Embase. RESULTS: A total of 17 studies involving 744 patients with LRRC were included; median OS ranging from 10 to 45 months (median: 24.5 months). Pooled 1-, 2-, and 3-year OS rates for all patients were 76.1%, 49.1%, and 38.3%, respectively. For patients who underwent re-irradiation and surgery (OP group), these pooled rates were 85.9%, 71.8%, and 51.7%, respectively. For patients who underwent re-irradiation but not surgery (non-OP group), pooled 1-, 2-, and 3-year OS rates were 63.5%, 34.2%, and 23.8%, respectively. The OS difference between both groups was significant for all 3 years (P < 0.05). Pooled 1-, 2-, and 3-year LC rates for the OP group were 84.4%, 63.8%, and 46.9%, and for the non-OP group were 72.0%, 54.8%, and 44.6%, respectively, without significant differences. Pooled grade ≥3 acute and late complication rates were 11.7% and 25.5% in the OP and non-OP groups, respectively. Patients who underwent surgery had a higher risk of grade ≥3 late complications (odds ratio: 6.39). Pooled symptomatic palliation rate was 75.2%. CONCLUSIONS: Re-irradiation with or without surgery for LRRC showed oncologic and palliative efficacy. Salvage treatment including re-irradiation and surgery showed higher survival, but the late complication was significantly increased with concomitant surgery.

Radioprotective effects of mistletoe extract in zebrafish embryos in vivo.

Introduction: Radioprotectors can enhance the efficacy of cancer radiotherapy, but their clinical use remains uncommon. The present study aimed to assess the radioprotective potential of mistletoe extract (commercial name: Abnoba Viscum), a well-known complementary cancer medicine, in zebrafish larvae. Materials and methods: Wild-type AB zebrafish embryos at 4 h-post-fertilization were exposed to 5 Gy 9-MeV electron beam irradiation after being treated for 1 h with 4 mMl/L amifostine or 0.2 mg/ml Abnoba Viscum A, F, M, or Q. Primary endpoints were abnormality-free survival and abnormality-free rates among survivors at 5 days-post-fertilization. Results: The crude abnormality-free survival rates were 33.7%, 49.0%, 38.8%, 43.9%, 38.1%, and 52.6%, whereas abnormality-free rates among survivors were 36.4%, 49.6%, 37.8%, 45.6%, 52.0%, and 62.8% for the control (with no pharmacologic treatment), amifostine, Abnoba Viscum A, F, M, and Q groups, respectively. Abnormality-free survival rates in the amifostine and Abnoba Viscum Q groups were significantly different from those in the control (p = .040 and .012, respectively), with an odds ratio (OR) of 1.90 [95% confidence interval (CI): 1.03-3.51] and 2.20 (95% CI: 1.19-4.08), respectively. Abnormality-free rates among survivors in the amifostine and Abnoba Viscum M and Q groups were significantly different from those in the control group (p = .048, .042, and <.001, respectively), with an OR of 1.79 (95% CI: 1.00-3.20), 1.82 (95% CI: 1.02-3.26), and 2.98 (1.67-5.33), respectively. Conclusion: Abnoba Viscum Q has at least a similar radioprotective effect to that of amifostine. Mistletoe extracts have been clinically applied for a long time and their effectiveness and feasibility have been verified. Abnoba Viscum Q might be a new candidate radioprotectant to enhance cancer radiotherapy efficacy.

Clinical Significance of Gender and Body Mass Index in Asian Patients with Colorectal Cancer.

Objective: Colorectal cancer is a disease closely associated with anthropometric values. This study aimed to evaluate the clinical relevance of gender and body mass index (BMI) with colorectal cancer using a Korean nationwide cohort. Methods: Data of colorectal cancer cohorts between 2012 and 2013 were acquired from the Health Insurance Review and Assessment Service. All patients underwent surgery due to colorectal cancers. Stage IV patients were excluded due to possible clinical heterogeneity. BMI was classified with the World Health Organization criteria. Results: A total of 31,756 patients were analyzed. The underweight group had 33% higher risk of stage III disease (p<0.001). The overweight and obese groups had 20% and 19% lower risk of stage III (p<0.001 and p=0.002, respectively). The underweight and obese groups had higher risk of longest hospitalization period quartile (≥19 days), with odds ratio of 2.26 (p<0.001) and 1.33 (p<0.001), respectively. The overweight group had a 22% lower risk of the longest hospitalization period quartile (p=0.002). Females had 12% lower risk of distal cancer than males (p<0.001). There was no significant relationship between cancer stage and gender. The proportions of patients who were <50 years and ≥70 years old were higher in the females, and the proportions of patients in their 50s and 60s were higher in the males. Conclusions: Cancer stages and hospitalization period varied depending on BMI. Disease location and the age distribution were affected by gender.

Is stereotactic body radiotherapy for ultra-central lung tumor a feasible option? A systemic review and meta-analysis.

INTRODUCTION: Ultra-central (UC) tumors, which are generally defined as tumors directly abutting the proximal bronchial tree, are difficult to treat with stereotactic body radiotherapy (SBRT) owing to possible serious complications. This systemic review and meta-analysis analyzed the early experiences and evaluated the efficacy and feasibility of SBRT for UC tumors. METHODS AND MATERIALS: The present study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Systemic searches of the EMBASE, PubMed, MEDLINE, and Cochrane library electronic databases were performed. The primary endpoints were two-year local control (LC), overall survival (OS), and grade ≥3 complication rates. A random-effects model was used to determine the pooled rates of the primary endpoints. Grade 5 complications were descriptively assessed. RESULTS: Nine studies involving 291 patients with UC tumors who underwent SBRT were included. The pooled two-year LC, two-year OS, and grade ≥3 complication rates were 96.7% (95% confidence interval [CI]: 91.0-98.9), 57.7% (95% CI: 32.0-79.8), and 23.2% (95% CI: 11.8-40.5), respectively. The incidence of grade 5 complication was 0-22% and was 0% in three of eight available studies. Hemorrhage (68.2%) was the commonest fatal complication. The risk factors for fatal hemoptysis included anticoagulant use, excessive maximum irradiation dose, endobronchial involvement, squamous histology, and bevacizumab exposure. CONCLUSIONS: SBRT for UC tumors confers efficient LC, although the risk of complications was not negligible. Control of possible risk factors of hemorrhage and dose optimization through further studies are warranted.

Sequential simulation computed tomography allows assessment of internal rectal movements during preoperative chemoradiotherapy in rectal cancer.

PURPOSES: The purpose of this study was to assess the internal rectal movement and to determine the factors related to extensive internal rectal movement using sequential simulation computed tomography (CT) images. MATERIALS AND METHODS: From 2010 to 2015, 96 patients receiving long-course preoperative chemoradiotherapy were included in our retrospective study. The initial simulation CT (Isim-CT) and follow-up simulation CT (Fsim-CT) for a boost were registered according to the isocenters and bony structure. The rectums on Isim-CT and Fsim-CT were compared on four different axial planes as follows: (1) lower pubis symphysis (AXVERYLOW), (2) upper pubis symphysis (AXLOW), (3) superior rectum (AXHIGH), and (4) middle of AXLOW and AXHIGH (AXMID). The involved rectum in the planning target volume was evaluated. The maximal radial distances (MRD), the necessary radius from the end of Isim-CT rectum to cover entire Fsim-CT rectum, and the common area rate (CAR) of the rectum (CAR, (Isim-CT∩Fsim-CT)/(Isim-CT)) were measured. Linear regression tests for the MRDs and logistic regression tests for the CARs were conducted. RESULTS: The mean ± standard deviation (mm) of MRDs and CAR <80% for AXVERYLOW, AXLOW, AXMID, and AXHIGH were 2.3 ± 2.5 and 8.9%, 3.0 ± 3.7 and 17.4%, 4.0 ± 5.2 and 27.1%, and 4.1 ± 5.2 and 25%, respectively. For MRDs and CARs, a higher axial level (AXVERYLOW/AXMID-HIGH, P = 0.018 and P = 0.034, respectively), larger bladder volume (P = 0.054 and P = 0.017, respectively), smaller bowel gas extent (small/marked, P = 0.014 and P = 0.001, respectively), and increased bowel gas change (decrease/increase, both P < 0.001) in rectum were associated with extensive internal rectal movement in multivariate analyses. CONCLUSIONS: As a result of following internal rectal movement through sequential simulation CT, the rectum above the pubis symphysis needs a larger margin, and bladder volume and bowel gas should be closely observed.

Radiotherapy for 65 patients with advanced unresectable hepatocellular carcinoma.

AIM: To evaluate the efficacy of radiotherapy (RT) in patients with advanced unresectable hepatocellular carcinoma (HCC). METHODS: A total of 65 patients were treated with RT in the Korea University Medical Center. The median age of the patients was 60 years, and 86.2% were men. 18.5% and 81.5% of the patients were diagnosed as TNM stage II and IV-A, respectively. Treatment response was assessed 4 mo after initiation of RT. Tumor regression rate 1 mo after initiation of RT (TRR1m) was also assessed. Duration of survival was calculated from the initiation of RT. RESULTS: The objective treatment response was 56.9%. The 12 mo survival rate was 34.7%. Predictive factors for survival were Child-Pugh grade, alpha-fetoprotein level and treatment response. An objective response was achieved more frequently in patients with TRR1m > or = 20% than in those with TRR1m < 20% (P < 0.001). CONCLUSION: RT is effective in treating advanced HCC with a tumor response rate of 56.9%.