Practice guidelines for managing extrahepatic biliary tract cancers.

Backgrounds/Aims: Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021. Methods: Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop. Results: In November 2021, the finalized draft was presented for public scrutiny during a formal hearing. Conclusions: The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Combined High Dose Radiotherapy with Sequential Gemcitabine-Cisplatin Based Chemotherapy Increase the Resectability and Survival in Locally Advanced Unresectable Intrahepatic Cholangiocarcinoma: A Multi-Institutional Cohort Study.

Purpose: The locally advanced unresectable intrahepatic cholangiocarcinoma (ICC) has detrimental oncological outcomes. In this study, we aimed to investigate the efficacy of radiotherapy in patients with locally advanced unresectable ICC. Materials and Methods: Between 2001 and 2021, 116 patients were identified through medical record who underwent radiotherapy for locally advanced unresectable ICC. The resectability of ICC is determined by the multidisciplinary team at each institution. Overall survival (OS) were analyzed using the Kaplan-Meier method, and prognostic factors were analyzed using the Cox proportional hazards model. Results: The median equivalent radiotherapy dose in 2 Gy fractions (EQD2) was 52 Gy (range, 30-110 Gy). Forty-seven patients (40.5%) received sequential gemcitabine-cisplatin based chemotherapy (GEM-CIS CTx). Multivariate analysis identified 2 risk factors, EQD2 of ≥60 Gy and application of sequential GEM-CIS CTx for OS. Patients were grouped by these two risk factors; group 1, EQD2 ≥60 Gy with sequential GEM-CIS CTx (n=25); group 2, EQD2 <60 Gy with sequential GEM-CIS CTx or fluoropyrimidine-based concurrent chemoradiotherapy (n=70); group 3, radiotherapy alone (n=21). Curative resection was more frequently undergone in group 1 than in groups 2 or 3 (28% vs. 8.6% vs. 0%, respectively). Consequently, OS was significantly better in group 1 than in groups 2 and 3 (p<0.05). Conclusion: Combined high dose radiotherapy with sequential GEM-CIS CTx improved oncologic outcomes in patients with locally advanced unresectable ICC. Further prospective studies are required to validate these findings.

Risk Factors for Distant Metastasis in Extrahepatic Bile Duct Cancer after Curative Resection (KROG 1814).

PURPOSE: Risk factors predicting distant metastasis (DM) in extrahepatic bile duct cancer (EHBDC) patients treated with curative resection were investigated. MATERIALS AND METHODS: Medical records of 1,418 EHBDC patients undergoing curative resection between Jan 2000 and Dec 2015 from 14 institutions were reviewed. After resection, 924 patients (67.6%) were surveilled without adjuvant therapy, 297 (21.7%) were treated with concurrent chemoradiotherapy (CCRT) and 148 (10.8%) with CCRT followed by chemotherapy. To exclude the treatment effect from innate confounders, patients not treated with adjuvant therapy were evaluated. RESULTS: After a median follow-up of 36.7 months (range, 2.7 to 213.2 months), the 5-year distant metastasis-free survival (DMFS) rate was 57.7%. On multivariate analysis, perihilar or diffuse tumor (hazard ratio [HR], 1.391; p=0.004), poorly differentiated histology (HR, 2.014; p < 0.001), presence of perineural invasion (HR, 1.768; p < 0.001), positive nodal metastasis (HR, 2.670; p < 0.001) and preoperative carbohydrate antigen (CA) 19-9 ≥ 37 U/mL (HR, 1.353; p < 0.001) were significantly associated with inferior DMFS. The DMFS rates significantly differed according to the number of these risk factors. For validation, patients who underwent adjuvant therapy were evaluated. In patients with ≥ 3 factors, additional chemotherapy after CCRT resulted in a superior DMFS compared with CCRT alone (5-year rate, 47.6% vs. 27.7%; p=0.001), but the benefit of additional chemotherapy was not observed in patients with 0-2 risk factors. CONCLUSION: Tumor location, histologic differentiation, perineural invasion, lymph node metastasis, and preoperative CA 19-9 level predicted DM risk in resected EHBDC. These risk factors might help identifying a subset of patients who could benefit from additional chemotherapy after resection.

Assessment of deep learning-based auto-contouring on interobserver consistency in target volume and organs-at-risk delineation for breast cancer: Implications for RTQA program in a multi-institutional study.

PURPOSE: To quantify interobserver variation (IOV) in target volume and organs-at-risk (OAR) contouring across 31 institutions in breast cancer cases and to explore the clinical utility of deep learning (DL)-based auto-contouring in reducing potential IOV. METHODS AND MATERIALS: In phase 1, two breast cancer cases were randomly selected and distributed to multiple institutions for contouring six clinical target volumes (CTVs) and eight OAR. In Phase 2, auto-contour sets were generated using a previously published DL Breast segmentation model and were made available for all participants. The difference in IOV of submitted contours in phases 1 and 2 was investigated quantitatively using the Dice similarity coefficient (DSC) and Hausdorff distance (HD). The qualitative analysis involved using contour heat maps to visualize the extent and location of these variations and the required modification. RESULTS: Over 800 pairwise comparisons were analysed for each structure in each case. Quantitative phase 2 metrics showed significant improvement in the mean DSC (from 0.69 to 0.77) and HD (from 34.9 to 17.9 mm). Quantitative analysis showed increased interobserver agreement in phase 2, specifically for CTV structures (5-19 %), leading to fewer manual adjustments. Underlying IOV differences causes were reported using a questionnaire and hierarchical clustering analysis based on the volume of CTVs. CONCLUSION: DL-based auto-contours improved the contour agreement for OARs and CTVs significantly, both qualitatively and quantitatively, suggesting its potential role in minimizing radiation therapy protocol deviation.

Suggestions for Escaping the Dark Ages for Pediatric Diffuse Intrinsic Pontine Glioma Treated with Radiotherapy: Analysis of Prognostic Factors from the National Multicenter Study.

PURPOSE: This multicenter retrospective study aimed to investigate clinical, radiologic, and treatment-related factors affecting survival in patients with newly diagnosed diffuse intrinsic pontine glioma (DIPG) treated with radiotherapy. MATERIALS AND METHODS: Patients aged <30 years who underwent radiotherapy as an initial treatment for DIPG between 2000 and 2018 were included; patients who did not undergo magnetic resonance imaging at diagnosis and those with pathologically diagnosed grade I glioma were excluded. We examined medical records of 162 patients collected from 10 participating centers in Korea. The patients' clinical, radiological, molecular, and histopathologic characteristics, and treatment responses were evaluated to identify the prognosticators for DIPG and estimate survival outcomes. RESULTS: The median follow-up period was 10.8 months (interquartile range, 7.5 to 18.1). The 1- and 2-year overall survival (OS) rates were 53.5% and 19.0%, respectively, with a median OS of 13.1 months. Long-term survival rate (≥ 2 years) was 16.7%, and median OS was 43.6 months. Age (< 10 years), poor performance status, treatment before 2010, and post-radiotherapy necrosis were independently associated with poor OS in multivariate analysis. In patients with increased post-radiotherapy necrosis, the median OS estimates were 13.3 months and 11.4 months with and without bevacizumab, respectively (p=0.138). CONCLUSION: Therapeutic strategy for DIPG has remained unchanged over time, and the associated prognosis remains poor. Our findings suggest that appropriate efforts are needed to reduce the occurrence of post-radiotherapy necrosis. Further well-designed clinical trials are recommended to improve the poor prognosis observed in DIPG patients.

Dummy run quality assurance study in the Korean Radiation Oncology Group 19 - 09 multi-institutional prospective cohort study of breast cancer.

BACKGROUND: The Korean Radiation Oncology Group (KROG) 19 - 09 prospective cohort study aims to determine the effect of regional nodal irradiation on regional recurrence rates in ypN0 breast cancer patients. Dosimetric variations between radiotherapy (RT) plans of participating institutions may affect the clinical outcome of the study. We performed this study to assess inter-institutional dosimetric variations by dummy run. METHODS: Twelve participating institutions created RT plans for four clinical scenarios using computed tomography images of two dummy cases. Based on a reference structure set, we analyzed dose-volume histograms after collecting the RT plans. RESULTS: We found variations in dose distribution between institutions, especially in the regional nodal areas. Whole breast and regional nodal irradiation (WBI + RNI) plans had lower inter-institutional agreement and similarity for 95% isodose lines than WBI plans. Fleiss's kappa values, which were used to measure inter-institutional agreement for the 95% isodose lines, were 0.830 and 0.767 for the large and medium breast WBI plans, respectively, and 0.731 and 0.679 for the large and medium breast WBI + RNI plans, respectively. There were outliers in minimum dose delivered to 95% of the structure (D95%) of axillary level 1 among WBI plans and in D95% of the interpectoral region and axillary level 4 among WBI + RNI plans. CONCLUSION: We found inter-institutional and inter-case variations in radiation dose delivered to target volumes and organs at risk. As KROG 19 - 09 is a prospective cohort study, we accepted the dosimetric variation among the different institutions. Actual patient RT plan data should be collected to achieve reliable KROG 19 - 09 study results.

Impact of Denoising on Deep-Learning-Based Automatic Segmentation Framework for Breast Cancer Radiotherapy Planning.

Objective: This study aimed to investigate the segmentation accuracy of organs at risk (OARs) when denoised computed tomography (CT) images are used as input data for a deep-learning-based auto-segmentation framework. Methods: We used non-contrast enhanced planning CT scans from 40 patients with breast cancer. The heart, lungs, esophagus, spinal cord, and liver were manually delineated by two experienced radiation oncologists in a double-blind manner. The denoised CT images were used as input data for the AccuContourTM segmentation software to increase the signal difference between structures of interest and unwanted noise in non-contrast CT. The accuracy of the segmentation was assessed using the Dice similarity coefficient (DSC), and the results were compared with those of conventional deep-learning-based auto-segmentation without denoising. Results: The average DSC outcomes were higher than 0.80 for all OARs except for the esophagus. AccuContourTM-based and denoising-based auto-segmentation demonstrated comparable performance for the lungs and spinal cord but showed limited performance for the esophagus. Denoising-based auto-segmentation for the liver was minimal but had statistically significantly better DSC than AccuContourTM-based auto-segmentation (p < 0.05). Conclusions: Denoising-based auto-segmentation demonstrated satisfactory performance in automatic liver segmentation from non-contrast enhanced CT scans. Further external validation studies with larger cohorts are needed to verify the usefulness of denoising-based auto-segmentation.

Use of lysates from pooled human mononuclear cells to activate CD3 T cells in humanized mice with low human cell engraftment efficiency.

In regenerative medicine, humanized mice (hu-mice) are extremely valuable for verifying the cross talk between immune cells and therapeutic cells. Given the highly dynamic nature of the activities of immune cells, the in vitro platform does not allow for screening of their exact interactions with different therapeutic cells. By contrast, hu-mice have been widely applied for in vivo studies, especially those on immune rejection. However, the full reconstitution of lymphoid lineage cells in hu-mice remains to be realized. In this study, we investigated whether lysates from healthy donor-derived pooled mononuclear cells (MNCs) can promote the increase of lymphoid lineage cells in hu-mice. The pooled MNC lysate treatment of hu-mice possessing a low proportion of CD45 cells resulted in significant increases in CD3 cells and CD45 cells with the RO phenotype. The diverse epitopes from the pooled MNC lysates significantly induced the proportion of lymphoid lineage cells in the thymus and spleen after therapeutic cells with mismatched HLAs were co-injected into the hu-mice. These findings demonstrate the technical benefits of using pooled MNC lysates for reconstituting lymphoid lineage cells in hu-mice, providing a valuable in vivo platform for investigating the cross talk between lymphoid immune cells and therapeutic cells.

The Role of Postoperative Radiotherapy in Intracranial Solitary Fibrous Tumor/Hemangiopericytoma: A Multi-institutional Retrospective Study (KROG 18-11).

PURPOSE: This study aimed to evaluate the role of postoperative radiotherapy (PORT) in intracranial solitary fibrous tumor/hemangiopericytoma (SFT/HPC). MATERIALS AND METHODS: A total of 133 patients with histologically confirmed HPC were included from eight institutions. Gross total resection (GTR) and subtotal resection (STR) were performed in 86 and 47 patients, respectively. PORT was performed in 85 patients (64%). The prognostic effects of sex, age, performance, World Health Organization (WHO) grade, location, size, Ki-67, surgical extent, and PORT on local control (LC), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) were estimated by univariate and multivariate analyses. RESULTS: The 10-year PFS, and OS rates were 45%, and 71%, respectively. The multivariate analysis suggested that PORT significantly improved LC (p < 0.001) and PFS (p < 0.001). The PFS benefit of PORT was maintained in the subgroup of GTR (p=0.001), WHO grade II (p=0.001), or STR (p < 0.001). In the favorable subgroup of GTR and WHO grade II, PORT was also significantly related to better PFS (p=0.028). WHO grade III was significantly associated with poor DMFS (p=0.029). In the PORT subgroup, the 0-0.5 cm margin of the target volume showed an inferior LC to a large margin with 1.0-2.0 cm (p=0.021). Time-dependent Cox proportion analysis showed that distant failures were significantly associated with poor OS (p=0.003). CONCLUSION: This multicenter study supports the role of PORT in disease control of intracranial SFT/HPC, irrespective of the surgical extent and grade. For LC, PORT should enclose the tumor bed with sufficient margin.

Role of adjuvant chemoradiotherapy and chemotherapy in patients with resected gallbladder carcinoma: a multi-institutional analysis (KROG 19-04).

OBJECTIVE: The effectiveness of adjuvant treatments for resected gallbladder carcinoma (GBC) has remained unclear due to lack of randomized controlled trials; thus, the aim of present study was to evaluate the role of adjuvant treatments, including chemoradiotherapy (CRT) and/or chemotherapy (CTx), in patients with resected GBC. METHODS: A total of 733 GBC patients who received curative-intent surgical resection were identified in a multi-institutional database. Of 733 patients, 372 (50.8%) did not receive adjuvant treatment, whereas 215 (29.3%) and 146 (19.9%) received adjuvant CTx and CRT, respectively. The locoregional recurrence-free survival (LRFS), recurrence-free survival (RFS), and overall survival (OS) of the adjuvant treatment groups were compared according to tumor stage (stage II vs. stage III-IV). RESULTS: In stage II disease (n = 381), the 5-year LRFS, RFS, and OS were not significantly different among the no-adjuvant therapy, CTx, and CRT groups, and positive resection margin, presence of perineural invasion, and Nx classification were consistently associated with worse LRFS, RFS, and OS in the multivariate analysis (P < 0.05). For stage III-IV (n = 352), the CRT group had significantly higher 5-year LRFS, RFS, and OS than the no-adjuvant therapy and CTx groups (67.8%, 45.2%, and 56.9%; 37.9%, 28.8%, and 35.4%; and 45.0%, 30.0%, and 45.7%, respectively) (P < 0.05). CONCLUSIONS: CRT has value as adjuvant treatment for resected GBC with stage III-IV disease. Further study is needed for stage II disease with high-risk features.

Role of adjuvant radiotherapy in extrahepatic bile duct cancer: A multicenter retrospective study (Korean Radiation Oncology Group 18-14).

PURPOSE: To evaluate the role of adjuvant radiotherapy (RT) after curative resection in patients with extrahepatic bile duct (EHBD) cancer. METHODS: Between January 2000 and December 2015, 1475 patients with EHBD cancer who underwent curative resection were accrued from 14 institutions in Korea. Among these, 959 patients did not receive any adjuvant therapy (RT(-) group), while 516 underwent postoperative RT with or without chemotherapy (RT(+) group). RESULTS: The median age was 67 years. Nodal involvement was present in 482 patients (32.7%), and resection margin was involved in 293 patients (19.9%). RT(+) group had more patients with proximal tumours, advanced tumours, nodal involvement, perineural invasion, and involved resection margin than RT(-) group (all p < 0.001). With a median follow-up of 36 months, there were 211 locoregional recurrences, 307 distant metastases and 322 combined locoregional and distant failures. On multivariate analysis incorporating age, tumour location, differentiation, pT classification, pN classification, perineural invasion and resection margin, adjuvant RT was associated with improved overall survival (hazard ratio, 0.74; 95% confidence interval, 0.63-0.86; p < 0.001). When RT(+) group was separated into RT alone, concurrent chemoradiotherapy (CCRT) and CCRT followed by chemotherapy, the greatest benefit was observed in patients treated with CCRT followed by chemotherapy (hazard ratio, 0.52; 95% confidence interval, 0.41-0.68). CONCLUSIONS: Adjuvant RT combined with chemotherapy improved survival outcomes of resected EHBD cancer patients. Considering the greatest benefit observed in patients receiving CCRT followed by chemotherapy, a randomised controlled trial comparing chemotherapy alone and CCRT followed by chemotherapy is urgently needed.

Functional recovery by colon organoid transplantation in a mouse model of radiation proctitis.

Radiation proctitis is the collateral damage that occurs to healthy cells during radiation treatment of pelvic malignancies. Conservative treatment of radiation proctitis can mitigate inflammatory symptoms, but, to date, no therapeutic options are available for direct recovery of the damaged colonic epithelium. The present study assessed the ability of colon organoid-based regeneration to treat radiation proctitis. Radiation proctitis was induced in mice by irradiating their recta, followed by enema-based transplantation of mouse colon organoids. The transplanted colon organoids were found to successfully engraft onto the damaged rectal mucosa of the irradiated mice, reconstituting epithelial structure and integrity. Lgr5+ stem cells were shown to be pivotal to colon organoid mediated regeneration. Endoscopic examination showed the efficacy of localized transplantation of colon organoids with fibrin glue to irradiated sites. These findings provide useful insights into the use of colon organoid-based regenerative therapy for the treatment of radiation proctitis.

The Korean Society for Neuro-Oncology (KSNO) Guideline for Adult Diffuse Midline Glioma: Version 2021.1.

BACKGROUND: There have been no guidelines for the management of adult patients with diffuse midline glioma (DMG), H3K27M-mutant in Korea since the 2016 revised WHO classification newly defined this disease entity. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for DMG since 2019. METHODS: The Working Group was composed of 27 multidisciplinary medical experts in Korea. References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of keywords. As 'diffuse midline glioma' was recently defined, and there was no international guideline, trials and guidelines of 'diffuse intrinsic pontine glioma' or 'brain stem glioma' were thoroughly reviewed first. RESULTS: The core contents are as follows. The DMG can be diagnosed when all of the following three criteria are satisfied: the presence of the H3K27M mutation, midline location, and infiltrating feature. Without identification of H3K27M mutation by diagnostic biopsy, DMG cannot be diagnosed. For the primary treatment, maximal safe resection should be considered for tumors when feasible. Radiotherapy is the primary option for tumors in case the total resection is not possible. A total dose of 54 Gy to 60 Gy with conventional fractionation prescribed at 1-2 cm plus gross tumor volume is recommended. Although no chemotherapy has proven to be effective in DMG, concurrent chemoradiotherapy (± maintenance chemotherapy) with temozolomide following WHO grade IV glioblastoma's protocol is recommended. CONCLUSION: The detection of H3K27M mutation is the most important diagnostic criteria for DMG. Combination of surgery (if amenable to surgery), radiotherapy, and chemotherapy based on comprehensive multidisciplinary discussion can be considered as the treatment options for DMG.

The Korean Society for Neuro-Oncology (KSNO) Guideline for Antiepileptic Drug Usage of Brain Tumor: Version 2021.1.

BACKGROUND: To date, there has been no practical guidelines for the prescription of antiepileptic drugs (AEDs) in brain tumor patients in Korea. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, had begun preparing guidelines for AED usage in brain tumors since 2019. METHODS: The Working Group was composed of 27 multidisciplinary medical experts in Korea. References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of the keywords. RESULTS: The core contents are as follows. Prophylactic AED administration is not recommended in newly diagnosed brain tumor patients without previous seizure history. When AEDs are administered during peri/postoperative period, it may be tapered off according to the following recommendations. In seizure-naïve patients with no postoperative seizure, it is recommended to stop or reduce AED 1 week after surgery. In seizure-naïve patients with one early postoperative seizure (<1 week after surgery), it is advisable to maintain AED for at least 3 months before tapering. In seizure-naïve patients with ≥2 postoperative seizures or in patients with preoperative seizure history, it is recommended to maintain AEDs for more than 1 year. The possibility of drug interactions should be considered when selecting AEDs in brain tumor patients. Driving can be allowed in brain tumor patients when proven to be seizure-free for more than 1 year. CONCLUSION: The KSNO suggests prescribing AEDs in patients with brain tumor based on the current guideline. This guideline will contribute to spreading evidence-based prescription of AEDs in brain tumor patients in Korea.

Adjuvant radiotherapy and chemotherapy offer a recurrence and survival benefit in patients with resected perihilar cholangiocarcinoma.

BACKGROUND AND OBJECTIVES: The objective of this study was to investigate the benefits of adjuvant treatment for patients with resected perihilar cholangiocarcinoma (PHC). METHODS: Between 2001 and 2017, 196 patients with PHC adenocarcinoma underwent curative resection. The patients were divided into four groups according to adjuvant treatment type: surgery alone (S; N = 90), surgery with chemotherapy (S+CTx; N = 67), surgery with radiotherapy (S+RTx; N = 18), and surgery with chemoradiotherapy (S+ CRTx; N = 21). RESULTS: The median follow-up duration of the surviving patients was 58 months. The 5-year rate of overall survival (OS) was 32%. In multivariate analysis, receiving S+CTx and S+CRTx were significant prognostic factors for OS. In subgroup analyses of the R1 resection patients, the S+CRTx group showed better OS than the S group (p < 0.05). In subgroup analyses of the stage III-IVA patients with a negative resection margin, the S+CTx and S+CRTx groups showed superior OS than the S group (p < 0.05). CONCLUSIONS: Our data suggest that adjuvant chemoradiotherapy might be considered for PHC patients with R1 resection. Adjuvant chemotherapy or chemoradiotherapy is suggested for stage III-IVA patients with R0 resection. The results of this study require validation through further prospective studies.

Impact of radiation dose on complications among women with breast cancer who underwent breast reconstruction and post-mastectomy radiotherapy: A multi-institutional validation study.

PURPOSE: Emerging data suggest that higher radiation doses in post-mastectomy radiotherapy may be associated with an increased risk of reconstruction complications. This study aimed to validate previous findings regarding the impact of radiation dose on complications among women with breast cancer using a multi-center dataset. METHODS: Fifteen institutions participated, and women with breast cancer who received radiotherapy after either autologous or prosthetic breast reconstruction were included. The primary endpoint was major post-radiation therapy complications requiring re-operation for explantation, flap failure, or bleeding control. RESULTS: In total, 314 patients were included. Radiotherapy was performed using both conventional fractionation and hypofractionation in various schedules. The range of the radiation therapy dose in Equivalent Dose in 2 Gy fractions (EQD2; α/ß = 3.5) varied from 43.4 to 71.0 Gy (median dose: 48.6 Gy). Boost radiation therapy was administered to 49 patients. Major post-radiation therapy complications were observed in 24 (7.6%) patients. In multivariate analysis, an increasing EQD2 per Gy (odds ratio [OR]: 1.58, 95% confidence interval [CI]: 1.26-1.98; p < 0.001), current smoking status (OR: 25.48, 95% CI: 1.56-415.65; p = 0.023), and prosthetic breast reconstruction (OR: 9.28, 95% CI: 1.84-46.70; p = 0.007) were independently associated with an increased risk of major complications. CONCLUSION: A dose-response relationship between radiation dose and the risk of complications was validated in this multi-center dataset. In this context, we hypothesize that the use of hypofractionated radiotherapy (40 Gy in 15 fractions) may improve breast reconstruction outcomes. Our multi-center prospective observational study (NCT03523078) is underway to further validate this hypothesis.

Clinical outcomes of hypofractionated radiotherapy for thyroid-associated ophthalmopathy.

OBJECTIVE: To evaluate the safety and effectiveness of hypofractionated orbital radiotherapy applied in the treatment of thyroid-associated ophthalmopathy (TAO) patients. METHODS: Between 2014 and 2018, we retrospectively reviewed the cases of 28 patients with TAO. All patients underwent radiotherapy on both retroocular tissues and received an oral steroid. Patients were divided into two treatment groups: 14 patients received conventional fractionated radiotherapy (20 Gy in 10 fractions), and the second group of 14 patients received hypofractionated radiotherapy (20 Gy in five fractions). The clinical activity score (CAS), NOSPECS (No physical signs or symptoms, Only signs, Soft tissue involvement, Proptosis, Extraocular muscle signs, Corneal involvement, and Sight loss) classification, Hess screen test and binocular single vision (BSV) were evaluated to determine the response to treatment before and at 1 month after radiotherapy. RESULTS: There were no significant differences in any of the variables between the two treatment groups. In both groups, the CAS and NOSPECS score decreased significantly, and the range of extraocular muscle motility in Hess screen test and BSV improved significantly after radiotherapy (p < 0.05). There were no significant differences in CAS, NOSPECS score, Hess screen test or BSV between the two groups. No radiation-related, acute severe toxicity was observed. CONCLUSION: Hypofractionated radiotherapy for TAO produced a comparable clinical outcome to that of conventional fractionated radiotherapy. Further case accumulation and long-term follow-up are required to determine if late toxicity occurs and to confirm efficacy. ADVANCES IN KNOWLEDGE: This is the first study to show that the efficacy and risk of adverse events are comparable between hypofractionated radiotherapy and conventional radiotherapy in the treatment of TAO.

Cryopreserved Human Oocytes and Cord Blood Cells Can Produce Somatic Cell Nuclear Transfer-Derived Pluripotent Stem Cells with a Homozygous HLA Type.

Human pluripotent stem cells (PSCs) through somatic cell nuclear transfer (SCNT) may be an important source for regenerative medicine. The low derivation efficiency of stem cells and the accessibility of human oocytes are the main obstacles to their application. We previously reported that the efficiency of SCNT was increased by overexpression of H3K9me3 demethylase. Here, we applied a modified derivation method to the PSC line and first obtained human SCNT-PSC lines derived from both donated cryopreserved oocytes and cord blood cells with a homozygous human leukocyte antigen (HLA) type. The SCNT-PSCs have very similar characteristics with embryonic stem cells (ESCs) and additionally have shown immunocompatibility in an in vitro and in vivo humanized mouse with a matching HLA type. Our study demonstrates that SCNT technology using donated cryopreserved oocytes and cord blood cells with a known HLA type provides a promising method for establishing a human HLA-matched SCNT-PSC bank for regenerative medicine.

Postoperative radiotherapy for WHO grade II-III intracranial ependymoma in adults: An intergroup collaborative study (KROG 18-06/KNOG 18-01).

BACKGROUND AND PURPOSE: To evaluate the impact of adjuvant postoperative radiotherapy (PORT) in adult WHO grade II-III intracranial ependymoma (IEPN). MATERIALS AND METHODS: A total of 172 pathologically confirmed adult grade II-III IEPN patients from 12 institutions were eligible. Of them, 106 (61.6%) and 66 (38.4%) patients were grade II and III, respectively. For grade II and III IEPNs, 51 (48.1%) and 59 (89.4%) patients received PORT, respectively. The median dose to the primary tumor bed was 54.0 Gy and 59.4 Gy for grade II and III patients, respectively. The prognostic impact of sex, age, performance, WHO grade, location, size, surgical extent, and PORT on local control (LC), progression-free survival (PFS), and overall survival (OS) were evaluated by univariate and multivariate analysis. RESULTS: The median follow-up period for survivors was 88.1 months. The 5-/10-year LC, PFS, and OS rates were 64.8%/54.0%, 56.4%/44.8%, and 76.6%/71.0%, respectively. On multivariate analysis, adjuvant PORT significantly improved LC (P = 0.002), PFS (P = 0.002), and OS (P = 0.043). Older age (P < 0.001), WHO grade III (P < 0.001), larger tumor size (P = 0.004), and lesser surgical extent (P < 0.001) were also negative factors for OS. Adjuvant PORT also improved LC (P = 0.010), PFS (P = 0.007), and OS (P = 0.069) on multivariate analysis for grade II IEPNs. CONCLUSION: This multicenter retrospective study supports the role of adjuvant PORT in terms of disease control and survival in adult grade II-III IEPNs. Prospective randomized trials focused on individualized treatment based on molecular subtypes is warranted.