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Background: Pathological diagnosis of small lung lesions is sometimes difficult in medically inoperable patients. The purpose of this study was to evaluate the adverse events and the outcomes of stereotactic body radiation therapy (SBRT) for lung lesions which were clinically diagnosed as primary lung cancer without pathological confirmation. Methods: Between April 2003 and April 2011, 88 patients with small lung lesions which were clinically diagnosed as primary lung cancer were treated with SBRT. The median tumor size was 19 mm (range 8-40 mm). The radiation dose was 48 Gy in four fractions in all patients. The median follow-up was 23 months (range 6-91 months). Results: Recurrence was observed in 13 patients. The local control rate, progression-free survival rate, and overall survival rate at 3 years were 90, 67, and 80 %, respectively. Two patients (2.3 %) had Grade 2 radiation pneumonitis, and six patients (6.8 %) had Grade 2 rib fractures. There were no adverse events of Grade 3 or greater. Conclusions: SBRT appears to be a safe and effective treatment option for small lung lesions that are clinically diagnosed as primary lung cancer without pathological confirmation. [ABSTRACT FROM AUTHOR]

Radiotherapy plays an important role in the treatment of various malignancies, and intensity-modulated radiotherapy (IMRT) is an attractive option because it can deliver precise conformal radiation doses to the target while minimizing the dose to adjacent normal tissues. IMRT provides a highly conformal dose distribution by modulating the intensity of the radiation beam. A number of malignancies have been targeted by IMRT; this work reviews published data on the major disease sites treated with IMRT. The dosimetric advantage of IMRT has resulted in the significant reduction of adverse effects in some tumors. However, there are few clinical trials comparing IMRT and three-dimensional conformal radiotherapy (3D-CRT), and no definite increase in survival or the loco-regional control rate by IMRT has been demonstrated in many malignancies. IMRT also requires greater time and resources to complete compared to 3D-CRT. In addition, the cost-effectiveness of IMRT versus 3D-CRT has not yet been established. [ABSTRACT FROM AUTHOR]

Purpose: To determine, in the setting of locally advanced pancreatic cancer, the maximum tolerated dose of carbon ion radiation therapy (C-ion RT) and gemcitabine dose delivered concurrently and to estimate local effect and survival.Methods and Materials: Eligibility included pathologic confirmation of pancreatic invasive ductal carcinomas and radiographically unresectable disease without metastasis. Concurrent gemcitabine was administered on days 1, 8, and 15, and the dose levels were escalated from 400 to 1000 mg/m(2) under the starting dose level (43.2 GyE) of C-ion RT. The dose levels of C-ion RT were escalated from 43.2 to 55.2 GyE at 12 fractions under the fixed recommended gemcitabine dose determined.Results: Seventy-six patients were enrolled. Among the 72 treated patients, dose-limiting toxicity was observed in 3 patients: grade 3 infection in 1 patient and grade 4 neutropenia in 2 patients. Only 1 patient experienced a late grade 3 gastric ulcer and bleeding 10 months after C-ion RT. The recommended dose of gemcitabine with C-ion RT was found to be 1000 mg/m(2). The dose of C-ion RT with the full dose of gemcitabine (1000 mg/m(2)) was safely increased to 55.2 GyE. The freedom from local progression rate was 83% at 2 years using the Response Evaluation Criteria in Solid Tumors. The 2-year overall survival rates in all patients and in the high-dose group with stage III (≥45.6 GyE) were 35% and 48%, respectively.Conclusions: Carbon ion RT with concurrent full-dose gemcitabine was well tolerated and effective in patients with unresectable locally advanced pancreatic cancer. [ABSTRACT FROM AUTHOR]

Purpose: Investigation of the treatment potential of carbon-ion radiation therapy in pelvic recurrence of rectal cancer.Methods and Materials: A phase 1/2 dose escalation study was performed. One hundred eighty patients (186 lesions) with locally recurrent rectal cancer were treated with carbon-ion radiation therapy (CIRT) (phase 1/2: 37 and 143 patients, respectively). The relapse locations were 71 in the presacral region, 82 in the pelvic sidewalls, 28 in the perineum, and 5 near the colorectal anastomosis. A 16-fraction in 4 weeks dose regimen was used, with total dose ranging from 67.2 to 73.6 Gy(RBE); RBE-weighted absorbed dose: 4.2 to 4.6 Gy(RBE)/fraction.Results: During phase 1, the highest total dose, 73.6 Gy(RBE), resulted in no grade >3 acute reactions in the 13 patients treated at that dose. Dose escalation was halted at this level, and this dose was used for phase 2, with no other grade >3 acute reactions observed. At 5 years, the local control and survival rates at 73.6 Gy(RBE) were 88% (95% confidence interval [CI], 80%-93%) and 59% (95% CI, 50%-68%), respectively.Conclusion: Carbon-ion radiation therapy may be a safe and effective treatment option for locally recurrent rectal cancer and may serve as an alternative to surgery. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to clarify the incidence, the clinical risk factors, and the dose–volume relationship of radiation-induced rib fracture (RIRF) after hypofractionated stereotactic body radiation therapy (SBRT). Methods and Materials: One hundred sixteen patients treated with SBRT for primary or metastatic lung cancer at our institution, with at least 6 months of follow-up and no previous overlapping radiation exposure, were included in this study. To determine the clinical risk factors associated with RIRF, correlations between the incidence of RIRF and the variables, including age, sex, diagnosis, gross tumor volume diameter, rib–tumor distance, and use of steroid administration, were analyzed. Dose–volume histogram analysis was also conducted. Regarding the maximum dose, V10, V20, V30, and V40 of the rib, and the incidences of RIRF were compared between the two groups divided by the cutoff value determined by the receiver operating characteristic curves. Results: One hundred sixteen patients and 374 ribs met the inclusion criteria. Among the 116 patients, 28 patients (46 ribs) experienced RIRF. The estimated incidence of rib fracture was 37.7% at 3 years. Limited distance from the rib to the tumor (<2.0 cm) was the only significant risk factor for RIRF (p = 0.0001). Among the dosimetric parameters used for receiver operating characteristic analysis, the maximum dose showed the highest area under the curve. The 3-year estimated risk of RIRF and the determined cutoff value were 45.8% vs. 1.4% (maximum dose, ≥42.4 Gy or less), 51.6% vs. 2.0% (V40, ≥0.29 cm3 or less), 45.8% vs. 2.2% (V30, ≥1.35 cm3 or less), 42.0% vs. 8.5% (V20, ≥3.62 cm3 or less), or 25.9% vs. 10.5% (V10, ≥5.03 cm3 or less). Conclusions: The incidence of RIRF after hypofractionated SBRT is relatively high. The maximum dose and high-dose volume are strongly correlated with RIRF. [Copyright &y& Elsevier]