PURPOSE: Toxicity of mucosa is one of the major concerns of radiotherapy (RT), when a target tumor is located near a mucosal lined organ. Energy of photon RT is transferred primarily by secondary electrons. If these secondary electrons could be removed in an internal cavity of mucosal lined organ, the mucosa will be spared without compromising the target tumor dose. The purpose of this study was to present a RT dose reduction in near target inner-surface (NTIS) of internal cavity, using Lorentz force of magnetic field. MATERIALS AND METHODS: Tissue equivalent phantoms, composed with a cylinder shaped internal cavity, and adjacent a target tumor part, were developed. The phantoms were irradiated using 6 MV photon beam, with or without 0.3 T of perpendicular magnetic field. Two experimental models were developed: single beam model (SBM) to analyze central axis dose distributions and multiple beam model (MBM) to simulate a clinical case of prostate cancer with rectum. RT dose of NTIS of internal cavity and target tumor area (TTA) were measured. RESULTS: With magnetic field applied, bending effect of dose distribution was visualized. The depth dose distribution of SBM showed 28.1% dose reduction of NTIS and little difference in dose of TTA with magnetic field. In MBM, cross-sectional dose of NTIS was reduced by 33.1% with magnetic field, while TTA dose were the same, irrespective of magnetic field. CONCLUSION: RT dose of mucosal lined organ, located near treatment target, could be modulated by perpendicular magnetic field.
Axis, Cervical Vertebra ; Magnetic Fields* ; Models, Theoretical ; Mucous Membrane ; Prostatic Neoplasms ; Radiation Injuries ; Radiotherapy* ; Rectum

Epithelioid hemangioendothelioma (EHE) is a rare benign vascular tumor, affecting fewer than one in a million individuals. Spinal EHE is exceptionally rare. This case report presents a case of recurrent spinal EHE, focusing on its clinical manifestation and providing a brief overview of its genetic characteristics. Seven years prior, a patient underwent subtotal resection of a lumbar and retroperitoneal EHE. Due to severe intraoperative bleeding, part of the lumbar spine mass was left unresected and subsequently treated with a moderate dose of radiation therapy. More recently, the patient presented with bilateral lower extremity weakness and urinary incontinence. Imaging studies revealed metastases in the thoracic and sacral bones, along with regrowth in the anterior portion of the previously treated spinal EHE. The patient underwent a series of operations to address both the regrowth and metastases, followed by intensity-modulated radiation therapy to target the remaining tumor tissue while minimizing damage to surrounding structures. Although EHE is generally considered benign, this indolent tumor has a tendency for persistent regrowth and metastasis. This case highlights the importance of radical resection and the potential role of higher radiation doses in preventing recurrence. Molecular testing may aid in achieving an accurate diagnosis and guiding effective treatment strategies.

Epithelioid hemangioendothelioma (EHE) is a rare benign vascular tumor, affecting fewer than one in a million individuals. Spinal EHE is exceptionally rare. This case report presents a case of recurrent spinal EHE, focusing on its clinical manifestation and providing a brief overview of its genetic characteristics. Seven years prior, a patient underwent subtotal resection of a lumbar and retroperitoneal EHE. Due to severe intraoperative bleeding, part of the lumbar spine mass was left unresected and subsequently treated with a moderate dose of radiation therapy. More recently, the patient presented with bilateral lower extremity weakness and urinary incontinence. Imaging studies revealed metastases in the thoracic and sacral bones, along with regrowth in the anterior portion of the previously treated spinal EHE. The patient underwent a series of operations to address both the regrowth and metastases, followed by intensity-modulated radiation therapy to target the remaining tumor tissue while minimizing damage to surrounding structures. Although EHE is generally considered benign, this indolent tumor has a tendency for persistent regrowth and metastasis. This case highlights the importance of radical resection and the potential role of higher radiation doses in preventing recurrence. Molecular testing may aid in achieving an accurate diagnosis and guiding effective treatment strategies.

Epithelioid hemangioendothelioma (EHE) is a rare benign vascular tumor, affecting fewer than one in a million individuals. Spinal EHE is exceptionally rare. This case report presents a case of recurrent spinal EHE, focusing on its clinical manifestation and providing a brief overview of its genetic characteristics. Seven years prior, a patient underwent subtotal resection of a lumbar and retroperitoneal EHE. Due to severe intraoperative bleeding, part of the lumbar spine mass was left unresected and subsequently treated with a moderate dose of radiation therapy. More recently, the patient presented with bilateral lower extremity weakness and urinary incontinence. Imaging studies revealed metastases in the thoracic and sacral bones, along with regrowth in the anterior portion of the previously treated spinal EHE. The patient underwent a series of operations to address both the regrowth and metastases, followed by intensity-modulated radiation therapy to target the remaining tumor tissue while minimizing damage to surrounding structures. Although EHE is generally considered benign, this indolent tumor has a tendency for persistent regrowth and metastasis. This case highlights the importance of radical resection and the potential role of higher radiation doses in preventing recurrence. Molecular testing may aid in achieving an accurate diagnosis and guiding effective treatment strategies.

Epithelioid hemangioendothelioma (EHE) is a rare benign vascular tumor, affecting fewer than one in a million individuals. Spinal EHE is exceptionally rare. This case report presents a case of recurrent spinal EHE, focusing on its clinical manifestation and providing a brief overview of its genetic characteristics. Seven years prior, a patient underwent subtotal resection of a lumbar and retroperitoneal EHE. Due to severe intraoperative bleeding, part of the lumbar spine mass was left unresected and subsequently treated with a moderate dose of radiation therapy. More recently, the patient presented with bilateral lower extremity weakness and urinary incontinence. Imaging studies revealed metastases in the thoracic and sacral bones, along with regrowth in the anterior portion of the previously treated spinal EHE. The patient underwent a series of operations to address both the regrowth and metastases, followed by intensity-modulated radiation therapy to target the remaining tumor tissue while minimizing damage to surrounding structures. Although EHE is generally considered benign, this indolent tumor has a tendency for persistent regrowth and metastasis. This case highlights the importance of radical resection and the potential role of higher radiation doses in preventing recurrence. Molecular testing may aid in achieving an accurate diagnosis and guiding effective treatment strategies.

PURPOSE: To evaluate the treatment results in early stage non-small cell lung cancer patients who have undergone fiducial-less CyberKnife radiosurgery (CKRS). MATERIALS AND METHODS: From June 2011 to November 2013, 58 patients underwent CKRS at Asan Medical Center for stage I lung cancer. After excluding 14 patients, we retrospectively reviewed the records of the remaining 44 patients. All analyses were performed using SPSS ver. 21. RESULTS: The median age at diagnosis was 75 years. Most patients had inoperable primary lung cancer with a poor pulmonary function test with comorbidity or old age. The clinical stage was IA in 30 patients (68.2%), IB in 14 (31.8%). The mean tumor size was 2.6 cm (range, 1.2 to 4.8 cm), and the tumor was smaller than 2 cm in 12 patients (27.3%). The radiation dose given was 48-60 Gy in 3-4 fractions. In a median follow-up of 23.1 months, local recurrence occurred in three patients (2-year local recurrence-free survival rate, 90.4%) and distant metastasis occurred in 13 patients. All patients tolerated the radiosurgery well, only two patients developing grade 3 dyspnea. The most common complications were radiation-induced fibrosis and pneumonitis. Eight patients died due to cancer progression. CONCLUSION: The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker. Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.
Carcinoma, Non-Small-Cell Lung* ; Chungcheongnam-do ; Comorbidity ; Diagnosis ; Dyspnea ; Fibrosis ; Fiducial Markers ; Follow-Up Studies ; Humans ; Lung ; Lung Neoplasms ; Neoplasm Metastasis ; Pneumonia ; Radiosurgery* ; Recurrence ; Respiratory Function Tests ; Retrospective Studies ; Survival Rate

PURPOSE: To evaluate the treatment results in early stage non-small cell lung cancer patients who have undergone fiducial-less CyberKnife radiosurgery (CKRS). MATERIALS AND METHODS: From June 2011 to November 2013, 58 patients underwent CKRS at Asan Medical Center for stage I lung cancer. After excluding 14 patients, we retrospectively reviewed the records of the remaining 44 patients. All analyses were performed using SPSS ver. 21. RESULTS: The median age at diagnosis was 75 years. Most patients had inoperable primary lung cancer with a poor pulmonary function test with comorbidity or old age. The clinical stage was IA in 30 patients (68.2%), IB in 14 (31.8%). The mean tumor size was 2.6 cm (range, 1.2 to 4.8 cm), and the tumor was smaller than 2 cm in 12 patients (27.3%). The radiation dose given was 48-60 Gy in 3-4 fractions. In a median follow-up of 23.1 months, local recurrence occurred in three patients (2-year local recurrence-free survival rate, 90.4%) and distant metastasis occurred in 13 patients. All patients tolerated the radiosurgery well, only two patients developing grade 3 dyspnea. The most common complications were radiation-induced fibrosis and pneumonitis. Eight patients died due to cancer progression. CONCLUSION: The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker. Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.
Carcinoma, Non-Small-Cell Lung* ; Chungcheongnam-do ; Comorbidity ; Diagnosis ; Dyspnea ; Fibrosis ; Fiducial Markers ; Follow-Up Studies ; Humans ; Lung ; Lung Neoplasms ; Neoplasm Metastasis ; Pneumonia ; Radiosurgery* ; Recurrence ; Respiratory Function Tests ; Retrospective Studies ; Survival Rate

BACKGROUND/AIMS: The aim of this study was to evaluate the efficacy of high definition (HD) i-SCAN for colorectal polyp detection in screening colonoscopy. METHODS: We retrospectively analyzed the records of 501 patients who had undergone screening colonoscopy performed by three endoscopists with either HD i-SCAN (n=149) or standard white light (n=352) from January 2, 2014 through June 30, 2014. Patient information and inter-endoscopist variation as well as polyp number, endoscopic findings, and pathologic characteristics were reviewed. RESULTS: The detection rates of colorectal and neoplastic polyps were significantly higher using HD i-SCAN than standard white light colonoscopy (52% vs. 38.1%, p=0.004 for colorectal polyps; and 37.2% vs. 27.9%, p=0.041 for neoplastic polyps). Analysis of endoscopic findings revealed no difference in detected polyp size between HD i-SCAN and standard white light colonoscopy (4.59+/-2.35 mm vs. 4.82+/-2.81 mm, p=0.739), but non-protruding polyps were more commonly detected by i-SCAN than by standard white light colonoscopy (24.6% vs. 13.5%, p=0.007). CONCLUSIONS: Colonoscopy using HD i-SCAN had a significantly higher detection rate of colorectal polyps, including neoplastic polyps, because of improved sensitivity for detecting non-protruding lesions.
Colonic Polyps ; Colonoscopy* ; Humans ; Mass Screening* ; Polyps* ; Retrospective Studies

In recent years, radiotherapy (RT) has been used to treat hepatocellular carcinoma (HCC) at each stage. This clinical trend has developed with the increasing improvement of RT techniques, which show clinical results comparable to those of other treatment modalities. Intensity-modulated radiotherapy uses a high radiation dose to improve treatment effectiveness. However, the associated radiation toxicity can damage adjacent organs. Radiation-induced gastric damage with gastric ulcers is a complication of RT. This report presents a novel management strategy for preventing post-RT gastric ulcers. We present the case of a 53-year-old male patient diagnosed with HCC, who experienced gastric ulcer after RT. Before the second round of RT, the patient was administered a gas-foaming agent, which was effective in preventing RT complications.

Background: Reference materials are essential for the quality assurance of molecular detection methods. We developed and characterized synthetic norovirus GI and GII RNA reference materials. Methods: Norovirus GI and GII RNA sequences including the ORF1–ORF2 junction region were designed based on 1,495 reported norovirus sequences and synthesized via plasmid preparation and in vitro transcription. The synthetic norovirus GI and GII RNAs were evaluated using six commercial norovirus detection kits used in Korea and subjected to homogeneity and stability analyses. A multicenter study involving five laboratories and using four commercial real-time PCR norovirus detection assays was conducted for synthetic norovirus RNA characterization and uncertainty measurements. Results: The synthetic norovirus GI and GII RNAs were positively detected using the six commercial norovirus detection kits and were homogeneous and stable for one year when stored at –20°C or –70°C. All data from the five laboratories were within a range of 1.0 log copies/μL difference for each RNA, and the overall mean concentrations for norovirus GI and GII RNAs were 7.90 log copies/μL and 6.96 log copies/μL, respectively. Conclusions The synthetic norovirus GI and GII RNAs are adequate for quality control based on commercial molecular detection reagents for noroviruses with high sequence variability. The synthetic RNAs can be used as reference materials in norovirus molecular detection methods.