Tae Gyu Kim

Endoscopic findings of rectal mucosal damage after pelvic radiotherapy for cervical carcinoma: correlation of rectal mucosal damage with radiation dose and clinical symptoms

Purpose To describe chronic rectal mucosal damage after pelvic radiotherapy (RT) for cervical cancer and correlate these findings with clinical symptoms and radiation dose. Materials and Methods Thirty-two patients who underwent pelvic RT were diagnosed with radiation-induced proctitis based on endoscopy findings. The median follow-up period was 35 months after external beam radiotherapy (EBRT) and intracavitary radiotherapy (ICR). The Vienna Rectoscopy Score (VRS) was used to describe the endoscopic findings and compared to the European Organization for Research and Treatment of Cancer (EORTC)/Radiation Therapy Oncology Group (RTOG) morbidity score and the dosimetric parameters of RT (the ratio of rectal dose calculated at the rectal point [RP] to the prescribed dose, biologically effective dose [BED] at the RP in the ICR and EBRT plans, α/β = 3). Results Rectal symptoms were noted in 28 patients (rectal bleeding in 21 patients, bowel habit changes in 6, mucosal stools in 1), and 4 patients had no symptoms. Endoscopic findings included telangiectasia in 18 patients, congested mucosa in 20, ulceration in 5, and stricture in 1. The RP ratio, BEDICR, BEDICR+EBRT was significantly associated with the VRS (RP ratio, median 76.5%; BEDICR, median 37.1 Gy3; BEDICR+EBRT, median 102.5 Gy3; p < 0.001). The VRS was significantly associated with the EORTC/RTOG score (p = 0.038). Conclusion The most prevalent endoscopic findings of RT-induced proctitis were telangiectasia and congested mucosa. The VRS was significantly associated with the EORTC/RTOG score and RP radiation dose.

Clinical outcomes of stereotactic body radiotherapy for spinal metastases from hepatocellular carcinoma

Purpose To investigate the outcomes of patients with spinal metastases from hepatocellular carcinoma (HCC), who were treated by stereotactic body radiotherapy (SBRT). Materials and Methods This retrospective study evaluated 23 patients who underwent SBRT from October 2008 to August 2012 for 36 spinal metastases from HCC. SBRT consisted of approximately 2 fractionation schedules, which were 18 to 40 Gy in 1 to 4 fractions for group A lesions (n = 15) and 50 Gy in 10 fractions for group B lesions (n = 21). Results The median follow-up period was 7 months (range, 2 to 16 months). Seven patients developed grade 1 or 2 gastrointestinal toxicity, and one developed grade 2 leucopenia. Compression fractures occurred in association with 25% of the lesions, with a median time to fracture of 2 months. Pain relief occurred in 92.3% and 68.4% of group A and B lesions, respectively. Radiologic response (complete and partial response) occurred in 80.0% and 61.9% of group A and B lesions, respectively. The estimated 1-year spinal-tumor progression-free survival rate was 78.5%. The median overall survival period and 1-year overall survival rate were 9 months (range, 2 to 16 months) and 25.7%, respectively. Conclusion SBRT for spinal metastases from HCC is well tolerated and effective at providing pain relief and radiologic response. Because compression fractures develop at a high rate following SBRT for spinal metastases from primary HCC, careful follow up of the patient is required.

Indications for endoscopy according to the revised FIGO staging for cervical cancer after MRI and CT scanning.

Objective A recent revision of the FIGO staging system does not recommend the mandatory use of cystoscopy and sigmoidoscopy. The objective of this study was to assess the clinical utility of CT or MRI scans for ruling out bladder or rectal invasion and determine the indication for endoscopy in patients with cervical cancer. Methods We retrospectively reviewed 769 patients with cervical cancer, who underwent imaging and endoscopic work-up between January 1997 and December 2010. Using endoscopy as the standard reference for comparison, we calculated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the imaging modality for bladder or rectal invasion. Results The CT scan showed 68.2% and 85.7% for sensitivity and 96.4% and 98.9% for specificity in detecting bladder and rectal invasion, respectively. CT scan provided a low PPV (51.7%, 54.5%) and a high NPV (98.2%, 99.8%). MRI scan showed 88.0% and 75.0% for sensitivity and 93.1% and 98.9% for specificity in detecting bladder and rectal invasion, respectively. MRI scan provided a low PPV (35.6%, 42.9%) and a high NPV (99.4%, 99.7%). The accuracies of CT and MRI scans in identifying bladder invasion were 94.9% and 92.8%, respectively. The accuracies of CT and MRI in identifying rectal invasion were 98.7% and 98.6%, respectively. Conclusion The results of this study demonstrate that additional invasive endoscopy is not necessary for patients who present with no invasion on imaging work-up, and therefore, endoscopy should be considered a tool for confirming cases that are positive for invasion based on imaging work-up.

High-dose radiation therapy alone by moderate hypofractionation for patients with thoracic esophageal squamous cell carcinoma.

Abstract We conducted retrospective analyses to investigate the clinical outcome of thoracic esophageal cancer patients who were treated with high-dose radiation therapy (RT) alone by moderate hypofractionation due to medical unfitness or refusal to receive either surgery or chemo-radiotherapy. Between May 2003 and April 2013, 70 patients were treated with high-dose RT alone with curative aim. The planned total RT dose was 60 Gy in daily 3.0 Gy per fraction. We evaluated the survival outcome, toxicities, and prognostic factors affecting patients’ survival. At the time of analysis, 32 patients experienced disease progression. The 2-year overall survival (OS), cancer-specific survival (CSS) and local control (LC) rates were 52.1%, 57.8%, and 68.2%, respectively. Among them, 25 patients had superficial (cT1a-b) esophageal cancers, and the 2-year OS, CSS, and LC rates were 80.0%, 87.3%, and 81.6%, respectively. Multivariate analysis revealed that cT disease (P < 0.001) and tumor location (P = 0.022) were the significant factors for OS. The incidence of grade 3 or higher toxicities were 9.9%, including grade 3 esophagitis (2 patients, 2.8%) and grade 4 or 5 trachea-esophageal fistula (5 patients, 7.1%). High-dose RT alone by moderate hypofractionation had led to reasonable clinical outcomes at acceptable toxicity risk in thoracic esophageal cancer patients who are medically unfit or refuse surgery or chemotherapy, especially for the patients having superficial lesion.

A Study of Factors influencing the Attitudes and Dispositions of Doping in Elite Golf Players

The purpose of this study is to identify the factors influencing the attitudes and dispositions of doping in elite golf players. 136 elite golfers (75 male, 61 female) were participated in this study and responded to Performance Enhancement Attitude Scale, Perfectionism in Sport Scale and Perceived Motivational Climate in Sport Questionnaire-2. Data that were collected analyzed by hierarchical multi regression. In male golfers, unequal recognition (UR) of coach had a positive effect on the attitudes and dispositions of doping, and rivalry (R) had a negative effect on that. In female golfers, Coach’s criticism (CC) had a positive effect on the attitudes and dispositions of doping. The effective anti-doping program which reflects the results of this study should be developed and implemented for elite golf players who need the anti-doping education.

Salvage Concurrent Chemo-radiation Therapy for Loco-regional Recurrence Following Curative Surgery of Non-small Cell Lung Cancer

Purpose This study is to report clinical outcomes of salvage concurrent chemo-radiation therapy (CCRT) in treating patients with loco-regional recurrence (LRR) following initial complete resection of non-small cell lung cancer. Materials and Methods Between February 2004 and December 2016, 127 patients underwent salvage CCRT for LRR. The median radiation therapy (RT) dose was 66 Gy and clinical target volume was to cover recurrent lesion with margin without elective inclusion of regional lymphatics. Majority of patients (94.5%) received weekly platinum-based doublet chemotherapy during RT course. Results The median follow-up time from the start of CCRT was 25 months. The median survival duration was 49 months, and overall survival (OS) rates at 2 and 5 years were 72.9% and 43.9%. The 2- and 5-year rates of in-field failure-free survival, distant metastasis free survival, and progression free survival were 82.4% and 73.8%, 50.4% and 39.9%, and 34.6% and 22.3%, respectively. Grade ≥ 3 radiation-related esophagitis and pneumonitis occurred in 14 (11.0%) and six patients (4.7%), respectively. On both univariate and multivariate analysis, higher biologically equivalent dose (BED10) (≥ 79.2 Gy10 vs. < 79.2 Gy10; hazard ratio [HR], 0.431), smaller CTV (≤ 80 cm3 vs. > 80 cm3; HR, 0.403), and longer disease-free interval (> 1 year vs. ≤ 1 year; HR, 0.489) were significantly favorable factors for OS. Conclusion The current study has demonstrated that high dose salvage CCRT focused to the involved lesion only was highly effective and safe. In particular, higher BED10, smaller CTV, and longer disease-free interval were favorable factors for improved survival.

Feasibility of Selective Neck Irradiation with Lower Elective Radiation Dose in Treating Nasopharynx Cancer Patients

Purpose This study aimed to report the clinical outcomes following selective neck irradiation (SNI) with lower elective radiation therapy (RT) dose in treating nasopharyngeal cancer (NPC) patients. Materials and Methods A total of 347 NPC patients received definitive RT according to our SNI policy and were retrospectively analyzed. The clinical target volumes (CTVs) were subdivided into CTV at high risk (CTV-HR) and CTV at low risk (CTV-LR). The typical doses to gross tumor volume (GTV), CTV-HR, and CTV-LR were 68.4-70.0 Gy, 54.0-60.0 Gy, and 36.0 Gy. Results With the median follow-up of 68.1 months (range, 2.3 to 197.1 months), the 5-year rates of loco-regional control and progression-free survival in all the patients were 85.0% and 70.8%, respectively. Thirty patients developed regional failure and the regional control rates at 3 and 5 years were 92.6% and 91.4%, respectively. The sites of regional failure in relation to the target volume were exclusively inside GTV/CTV-HR in 20, inside and outside GTV/CTVHR in three, and exclusively outside GTV/CTV-HR in seven, which were 5.7%, 0.9%, and 2.0% of total patients, respectively. Conclusion The clinical outcomes by the current SNI policy were feasible and comparable to those following classic elective nodal irradiation policy.

Effect of leukocyte alteration on treatment outcomes following preoperative chemoradiotherapy in patients with rectal cancer

Purpose Hematotoxicity following anti-cancer treatment is known to be related to treatment efficacy in several malignancies. The purpose of this study was to examine the hematologic parameters related to the tumor response and survival in patients treated with curative surgery following preoperative chemoradiotherapy (CRT) for rectal cancer. Materials and Methods Four hundred eighteen patients with rectal cancer who underwent preoperative CRT and curative surgery were analyzed, retrospectively. The main clinical factors and blood cell counts before and after CRT were investigated with respect to their relationships with tumor downstaging and patient survival. Results The post-CRT leukocyte count was significantly different between the tumor downstaging group and the nondownstaging group (median, 4740/uL vs. 5130/uL; p = 0.013). Multivariate analysis showed that histological grade, circumferential extent, and post-CRT leukocyte count were related to tumor downstaging. In addition, histological grade, post-CRT leukocyte count, and tumor downstaging were related to disease-free survival. The 5-year disease-free survival and overall survival in patients with post-CRT leukocyte count ≤3730/uL, which is the cut-off value derived from the receiver operation characteristic (ROC) curve analysis, were significantly higher than those with higher counts (88.0% vs. 71.6%, p = 0.001; 94.4% vs. 84.1%, p = 0.024). Conclusion Post-CRT leukocyte count of ≤3730/uL could be regarded as a good prognostic factor for tumor response and survival in rectal cancer patients treated with preoperative CRT.

Short-term effects of sports taping on navicular height, navicular drop and peak plantar pressure in healthy elite athletes: A within-subject comparison

Abstract Medial tibial stress syndrome (MTSS) is one of the most common exercise-induced leg pain. The navicular drop (ND) was identified as a risk factor for MTSS. This study aimed to evaluate the short-term effects of sports taping applied to the supporting lower leg during sitting, standing, walking, and jogging to restrict the ND in healthy elite athletes. Twenty-four healthy elite athletes without a history of exercise-induced pain or injuries in the lower limbs participated in this study (median age: 21.00 years; 1st--3rd quartiles; 19.25–22.00). The 4 taping conditions were used: rigid taping (RT), kinesiology taping (KT), placebo taping (PT), and non-taping (NT). The order of taping techniques was randomly assigned. Normalized navicular height (NH), ND, and normalized ND evaluated using 3-dimensional motion analysis, and normalized peak plantar pressure (PP) were compared in 4 taping conditions during sitting, standing, walking, and jogging. During sitting, the normalized NH of RT is higher than that of NT, KT, and PT (&khgr;2 = 17.30, P = .001), while during jogging, the normalized NH of RT is higher than that of NT and PT (&khgr;2 = 10.55, P = .014). The normalized peak PP of NT is higher than that of PT (&khgr;2 = 8.871, P = .031) in the lateral midfoot region. This study showed the RT technique maintained NH during sitting and jogging, and the RT technique could be an effective preventive and treatment strategy for MTSS.

SU‐FF‐T‐322: Statistical Analysis of Failures of a Medical Linear Accelerator Over Ten Years

Purpose: In order for better management of a medicallinear accelerator. the records of the operational failures of Varian CL2100C over ten years were analyzed.Method and Materials: The failures were classified according to the involved functional subunits and each class was rated into three levels depending on operational conditions. The relationship between the failure rate and working ratio and the relationship between the failure rate and outside temperature were investigated. in addition, the average life time of main part and operating efficiency for last 4 years were analysed.Results: Among the recorded failures ( total 587 failures), the most frequent failure, which was 20% of the total, was observed in the parts related to the collimation system including monitor chamber. Regarding to the operational conditions, the 2nd level of failures, that temporally interrupted treatments, was the most frequent. The 3rd level of failures, that interrupted treatment for more than several hours, was mostly caused by the accelerating subunit. The number of failures was increased with number of treatments and used time. The average life‐time of a Klystron and Thyratron became shorter as the working ratio increased, which was 42 and 83% of the expected values, respectively. The operating efficiency of 95% or higher was maintained, but value slightly decreased. There were no significant correlations between the number of failures and outside temperature. Conclusion: Recording equipment problems and failures in detail over a long period of time can provide a good knowledge of equipment function as well as the capability to forecast future failure. More rigorous equipment maintenance is required for old medicallinear accelerator to avoid the serious failure in advance, and improve the patient treatment quality.