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Objective: Stereotactic body radiation therapy (SBRT) for the treatment of a malignancy in the liver requires the perilesional implantation of fiducial markers for lesion detection. The purpose of this study is to evaluate the efficacy and safety of ultrasound (US) -guided marker implantation for SBRT. Methods: We retrospectively reviewed 299, US–guided, intrahepatic fiducial markers implanted in 101 patients between November 2013 and September 2014. SBRT-planning CT images were analyzed to determine the technical success of the implantation, the mean distance between the tumor margin and the marker, with the ideal location of fiducials defined as the distance between a marker and a tumor less than 3 cm and the distance between markers greater than 2 cm according to the tumor conspicuity seen on gray-scale US and the artifact obscuring tumor margins. We also evaluated procedure-related major and minor complications. Results: Technical success was achieved in 291 (97.3%) fiducial marker implantations. The mean distance between the tumor and the marker was 3.1 cm (S.D., 2.1 cm; range, 0–9.5 cm). Of 101 patients, 72 lesions (71.3%, 2.2 ± 1.0 cm; range, 0–3.0 cm) had fiducial markers located in an ideal location. The ideal location of fiducials was more common in visible lesions than in poorly conspicuous lesions (90.2% vs. 52.0%, P < 0.001). Seventeen markers (5.8%) developed beam-hardening artifacts obscuring the tumor margins. There were no major complications, although 12 patients (11.9%) developed minor complications. Conclusions: US-guided implantation of fiducial markers in the liver is an effective and safe procedure with only rare complications. [ABSTRACT FROM AUTHOR]

• Sparse local sampling and adaptive subtractive differential equalization were proposed to increase the channel capacity. • The 32% compressed mixed signal was transmitted using the sparse local sampling at the BER threshold (8 × 10−5). • In case of NRZ–OOK signal, input signal to noise ratio (SNR) gain of 14 dB is observed using two techniques at the same time. • The transmission rate of 11.824 Gb/s is achieved within 2–GHz bandwidth in the optical access link. We propose a new technique of simultaneously transmitting non–return–to–zero on–off–keying (NRZ–OOK) signal and discrete multitone (DMT) encoded by 16–quadrature amplitude modulation (QAM) signal within the same bandwidth in order to increase the transmission capacity of the optical access link. It is implemented by sequentially applying two techniques. The first proposed sparse local sampling technique compresses the length of the signal, which is mixed with the NRZ–OOK signal and the DMT signal, so that more data can be transmitted per unit time. The compressed mixed signal is recovered using the L 1 –minimization technique based on compressive sensing. The second proposed adaptive subtractive differential equalization (ASDE) technique recovers the NRZ–OOK signal by attenuating the portion corresponding to the DMT signal in the mixed signal after the mixed signal is transmitted. Thereafter, it recovers the DMT signal by subtracting the recovered NRZ–OOK signal from the mixed signal. A 20–km optical access link is implemented to verify the proposed technique. It is found that the mixed signal can be transmitted by reducing its length by 32 % using the sparse local sampling at the bit error rate (BER) threshold (8 × 10−5) of the 1st generic forward error correction (GFEC, RS(255,239)). In case of NRZ–OOK signal, input signal to noise ratio (SNR) gain of 14 dB is observed using two techniques at the same time. Also, input DMT signal with the SNR of greater than 35 dB can be transmitted. As a result, the transmission rate of 11.824 Gb/s (NRZ–OOK: 1 Gb/s + 0.32 Gb/s = 1.32 Gb/s, 16–QAM: 7.9576 Gb/s + 2.5464 Gb/s = 10.504 Gb/s) is achieved within 2–GHz bandwidth when the empty space is filled with other signals after sparse local sampling. These results indicate that the transmission capacity can be increased 5.912 times compared to the physical bandwidth of 2 GHz. [ABSTRACT FROM AUTHOR]

Purpose: This study compared a tablet PC questionnaire with a paper method for reliability and patient preferences in the acquisition of patient-reported outcomes (PROs) for patients treated with radiotherapy. By comparing the two modes of PRO administration, we aimed to evaluate the adequacy of using tablet PC questionnaires in future clinical use.Methods: Patients were randomized in a crossover study design using two different methods for PRO entry. A group of 89 patients answered a paper questionnaire followed by the tablet PC version, whereas 89 patients in another group completed the tablet PC questionnaire followed by the paper version. Surveys were performed four times per patient throughout the course of the radiotherapy. The Korean versions of the M.D. Anderson Symptom Inventory (MDASI-K) and the Brief Fatigue Inventory (BFI-K) were used. The primary endpoint of our current study was an assessment of patient preference for the survey method. The proportions of patients preferring each mode of questionnaire were evaluated.Results: The proportion of patients who preferred the tablet PC version, paper form, or who had no preference was 52.2, 22.1, and 25.7 %, respectively. More than half of the patients preferred the tablet PC to the paper version in all four surveys. Age, gender, educational status, prior experience of using a tablet PC, and the order of paper to tablet PC administration did not impact patient preferences. Inter-class correlation coefficients (ICCs) between the modes were 0.92 for MDASI-K and 0.94 for BFI-K and ranged from 0.91 to 0.96 on both instruments during the four surveys.Conclusions: A tablet PC-based PRO is an acceptable and reliable method compared with paper-based data collection for Korean patients receiving radiotherapy. [ABSTRACT FROM AUTHOR]

Purpose This study aimed to examine bone health status, identify factors associated with bone mineral density (BMD), and determine potential risk factors for osteoporosis in Korean prostate cancer patients receiving androgen deprivation therapy (ADT). Methods Using a cross-sectional descriptive design, we recruited 139 men with prostate cancer receiving ADT at two university-based hospitals in South Korea. Participants completed a self-reported questionnaire and underwent dual energy X-ray absorptiometry testing. BMD (gm/cm 2 ), bone health status (normal BMD, osteopenia, and osteoporosis), and lifestyle variables (physical activity, smoking, and alcohol consumption) were measured. Results The prevalence in our sample was 49.6% for osteopenia and 17.3% for osteoporosis. In multivariate linear regression analyses, BMD was positively associated with body mass index, number of comorbidities, and level of physical activity and negatively associated with being unemployed or retired, having a lower monthly income, and being treated with gonadotropin-releasing hormone therapy alone. In logistic regression analyses, potential risk factors for osteoporosis were low monthly income (OR = 4.33, p = 0.011), receipt of radiation therapy (OR = 4.69, p = 0.018), and lack of regular physical activity (OR = 2.63, p = 0.035). Conclusions Our results suggest that a proportion of prostate cancer survivors who are receiving ADT warrant monitoring to prevent osteoporosis, particularly men of lower economic status and those having lower levels of physical activity. Nurses can play an important role in screening these high risk groups. [ABSTRACT FROM AUTHOR]

Introduction: The present study evaluated the threshold dose for hepatic parenchymal changes on gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance (MR) images after stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma (HCC). Methods: Twenty patients with available data of follow-up MR images acquired 2-4 months after completion of SBRT were selected among the registered patients. SBRT was performed using multiple coplanar and non-coplanar beams with energies of 6 or 15 MV. All patients were treated with doses of 45 Gy administered in three fractions over 3 consecutive days. For image registration between planning computed tomography (CT) and MR images, landmark-based rigid body registration was performed using MIM software. Results: Seventeen patients were included in the analysis. The median discrepancies between planning CT and MR images in the left-right, anterior-posterior and superior-inferior directions were 1.38 mm, 1.24 mm and 1.72 mm, respectively. The median D50 value for the defect in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MR images after SBRT was 19.8 Gy (range, 14.2-28.7 Gy), with R(2) values ranging from 0.76 to 0.99. Conclusions: The threshold dose for parenchymal changes in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MR images performed 2-4 months after 45 Gy of SBRT in three fractions was approximately 20 Gy. Our results provide the basis for further research on the functional loss of liver parenchyma after SBRT. [ABSTRACT FROM AUTHOR]

Background: To assess the significance of alpha-fetoprotein (AFP) normalization as a prognostic surrogate after stereotactic body radiotherapy (SBRT) for patients with small hepatocellular carcinoma (HCC).Methods: Patients who underwent SBRT for primary or recurrent HCC were registered and a database thereof was retrospectively reviewed. Among 165 total registered patients, 77 patients were selected who satisfied the following criteria: (1) their AFP levels were > 20 ng/mL before SBRT, and (2) their AFP levels were checked within three months after SBRT. Propensity score based matching analysis was performed to minimize potential confounding bias. AFP normalization was defined as a reduction of AFP level to ≤ 20 ng/mL. Overall survival (OS) and progression-free survival (PFS) curves were estimated by the Kaplan-Meier method.Results: Thirty-seven (48.1 %) patients displayed AFP normalization (normalized group), while 40 (51.9 %) patients comprised the non-normalized group. The OS rates at 3-year were 62.0 % and 44.0 % (p = 0.023), and the PFS rates at 3-year were 27.9 % and 12.0 % (p = 0.019), in the normalized and non-normalized groups, respectively. Local control rates were 97.2 % in the normalized group and 94.7 % in the non-normalized group at three years (p = 0.579). In the propensity score matching cohort (25 pairs), OS and PFS were significantly longer in the normalized group than in the non-normalized group (p = 0.017 and 0.049, respectively). The local control rates were 100 % in both matched groups.Conclusions: AFP normalization within three months after SBRT is a prognostic surrogate for OS and PFS in patients with small HCC. AFP monitoring should be considered a useful tool for HCC patients with an elevated AFP level before SBRT. [ABSTRACT FROM AUTHOR]