Prognostic factors in hepatocellular carcinoma patients with bone metastases

PURPOSE: To identify the prognostic factors that could influence survival and to compare prognoses of the patients with the number of the risk factors that might assist in the adequate management of hepatocellular carcinoma (HCC) patients with bone metastases that showed a heterogeneous range of survival. MATERIALS AND METHODS: A total of 41 patients, treated with radiotherapy (RT) for bone metastases from HCC from 2014 to 2017, were enrolled retrospectively. Survival was determined by the Kaplan–Meier method from the start of the RT for metastatic bone lesions. Pre-RT clinical features were evaluated and their influences on survival were analyzed. The significant factors were considered to compare survivals according to the number of prognostic factors. RESULTS: Median follow-up was 6.0 months (range, 0.5 to 47.0 months). The median overall survival was 6.5 months, and the 1-year and 2-year survival rates were 35.5% and 13.5%, respectively. Multivariate analysis revealed that the Child-Pugh class A group, alpha-fetoprotein increased more than 30 ng/mL, and HCC size of more than 5 cm were associated with worse overall survival. The median survivals in HCC with none, 1, 2, and 3 of the aforementioned risk factors were 19.5, 9.0, 2.5, and 1.0 months, respectively (p < 0.05). CONCLUSION: Our results show that the overall survivals were significantly different according to the number of the risk factors among HCC patients with bone metastases who showed various lengths of survival.

Maximum diameter versus volumetric assessment for the response evaluation of vestibular schwannomas receiving stereotactic radiotherapy

PURPOSE: To explore the feasibility of maximum diameter as a response assessment method for vestibular schwannomas (VS) after stereotactic radiosurgery or fractionated stereotactic radiotherapy (RT), we analyzed the concordance of RT responses between maximum diameters and volumetric measurements. MATERIALS AND METHODS: Forty-two patients receiving curative stereotactic radiosurgery or fractionated stereotactic RT for VS were analyzed retrospectively. Twelve patients were excluded: 4 did not receive follow-up magnetic resonance imaging (MRI) scans and 8 had initial MRI scans with a slice thickness >3 mm. The maximum diameter, tumor volume (TV), and enhanced tumor volume (ETV) were measured in each MRI study. The percent change after RT was evaluated according to the measurement methods and their concordances were calculated with the Pearson correlation. The response classifications were determined by the assessment modalities, and their agreement was analyzed with Cohen kappa statistics. RESULTS: Median follow-up was 31.0 months (range, 3.5 to 86.5 months), and 90 follow-up MRI studies were analyzed. The percent change of maximum diameter correlated strongly with TV and ETV (r(p) = 0.85, 0.63, p = 0.000, respectively). Concordance of responses between the Response Evaluation Criteria in Solid Tumors (RECIST) using the maximum diameters and either TV or ETV were moderate (kappa = 0.58; 95% confidence interval, 0.32-0.85) or fair (kappa = 0.32; 95% confidence interval, 0.05-0.59), respectively. CONCLUSION: The percent changes in maximum diameter and the responses in RECIST were significantly concordant with those in the volumetric measurements. Therefore, the maximum diameters can be used for the response evaluation of VS following stereotactic RT.

Development of Prototype Quality Assurance Procedure for Blood Irradiator Using Glass Dosimeter Jig / 의학물리

For the purpose of quality assurance (QA) of the blood irradiator, QA programs for daily, monthly, and yearly were developed. For daily tests, simple items for basically operating the machine are recommended. For monthly and yearly tests, the measurement of dose to assure the dose delivery system are performed by a dosimetry devices (Glass dosimeter jig) developed in this study. The QA program is practical for clinical environment.

Study on the Evaluation of TRS-398 Quality Factors with Central Electrode Corrections for Small Cylindrical Chambers / 의학물리

The quality factors (kQ,Q0) were evaluated by appling the results recently studied for the effect of central electrode in TRS-398 protocol. The PTW-31010 and IBA-CC13 chambers were used in this study. The quality factors were calculated as a function of beam quality for high energy electron and photon beams and compared with data currently used in TRS-398 protocol. In the PTW-31010 chamber using aluminium electrode, appling the new central electrode collections, the quality factors were 0.4% and 0.9% higher than current TRS-398 data for high energy photon and electron beams respectively. In the IBA-CC13 chamber using C-552 electrode, there are no variations in quality factors compared to TRS-398 data currently used.