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Purpose To determine current practice patterns with regard to gynecologic high-dose-rate (HDR) brachytherapy among international members of the Gynecologic Cancer Intergroup (GCIG) in Japan/Korea (Asia), Australia/New Zealand (ANZ), Europe (E) and North America (NAm). Materials and Methods A 32-item survey was developed requesting information on brachytherapy practice patterns and standard management for Stage IB-IVA cervical cancer. The chair of each GCIG member cooperative group selected radiation oncology members to receive the survey. Results A total of 72 responses were analyzed; 61 respondents (85%) utilized HDR. The three most common HDR brachytherapy fractionation regimens for Stage IB-IIA patients were 6 Gy for 5 fractions (18%), 6 Gy × 4 (15%), 7 Gy × 3 (11%), and for Stage IIB-IVA patients were 6 Gy for 5 fractions (19%), 7 Gy × 4 (8%), and 7 Gy × 3 (8%). Overall, the mean combined external-beam and brachytherapy equivalent dose (EQD2) was 81.1 (standard deviation [SD], 10.16). The mean EQD2 recommended for Stage IB-IIA patients was 78.9 Gy (SD, 10.7) and for Stage IIB-IVA was 83.3 Gy (SD, 11.2) (p=0.02). By region, the mean combined EQD2 was: Asia, 71.2 Gy (SD, 12.65); ANZ, 81.18 (SD, 4.96); E, 83.24 (SD, 10.75); and NAm, 81.66 (SD, 6.05; p=0.02 for Asia vs. other regions). The ratio of brachytherapy to total prescribed dose was significantly higher for Japan (p=0.0002). Conclusion Although fractionation patterns may vary, the overall mean dose administered for cervical cancer is similar in Australia/New Zealand, Europe and North America, with practitioners in Japan administering a significantly lower external-beam dose but higher brachytherapy dose to the cervix. Given common goals, standardization should be possible in future clinical trials.

BACKGROUND Optimal management of postoperative radiotherapy for patients with completely resected thymoma remains controversial. This study was conducted to assess the efficacy of postoperative mediastinal irradiation in patients with completely resected thymoma. METHODS The records of 103 patients with completely resected thymoma who received postoperative mediastinal irradiation during the period between 1979 and 1998 were reviewed. The distribution according to Masaoka stage was Stage I in 17 patients, Stage II in 61 patients, and Stage III in 25 patients. Fifty‐two patients were treated with involved field (IF) irradiation, and 51 patients were treated with irradiation of the whole mediastinal field with or without boost (WM irradiation). The total radiation dose to the primary tumor bed was 30–61 grays (Gy), with a median dose of 40 Gy. No patients received chemotherapy during the initial treatment. The median follow‐up of the 82 living patients was 112 months (range, 24–244 months). RESULTS The 10‐year actuarial overall and disease free survival rates for all patients were 81% and 79%, respectively. The 10‐year actuarial overall survival rate was 100% for patients with Stage I disease, 90% for patients with Stage II disease, and 48% for patients with Stage III disease. In the analysis, clinical stage alone had a statistically significant impact on both overall survival and disease free survival (P < 0.0001 for both). Recurrent disease was observed in 17 patients, and the pleura was the most frequent site of first recurrence. Of 12 patients who had pleural recurrences, 11 patients had pleural dissemination remote from the initial tumor site. No recurrence was observed in any of the 17 patients with Stage I disease, and 6 of 61 patients (10%) with Stage II disease and 11 of 25 patients (44%) with Stage III disease experienced recurrences. With regard to intrathoracic recurrences, there were no recurrences within the irradiated field in any of the 103 patients, and no dose response correlation was seen in intrathoracic control (incidence of intrathoracic recurrence: 2 of 19 patients in the group that received < 40 Gy, 6 of 45 patients in the group that received 40 Gy, and 7 of 39 patients in the group that received > 40 Gy). With respect to treatment field, mediastinal recurrences were observed in 4 of 52 patients (8%) who were treated with IF irradiation, whereas 0 of 51 patients who were treated with WM irradiation experienced mediastinal recurrences. Pleural‐based recurrences were observed both in patients who were treated with IF irradiation (7 of 52 patients) and in patients who were treated with WM irradiation (5 of 51 patients). According to the degree of pathologic tumor invasion, 0 of 71 patients without pleural invasion had pleural‐based recurrences (0 of 17 patients with Stage I disease, 0 of 51 patients with Stage II disease, and 0 of 3 patients with Stage III disease), whereas 12 of 32 patients (38%) with pleural invasion had pleural‐based recurrences (4 of 10 patients with Stage II disea...

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Ionic liquids with their limitless combination of cations and anions can offer an optimal solvent for a specific purpose. But not all corresponding experimental studies are possible as they will be time consuming and expensive. A judicious screening of the various possible solvents is required to select the proper ionic liquid. Conductor‐like screening model (COSMO) along with its extension to real solvents can be used for these predictions. In this work, modified version COSMO_LL has been used to predict the liquid–liquid equilibria (LLE) for 32 ternary systems, available in literature, each having an ionic liquid. A complete dissociation of cations and anions of the ionic liquid has been assumed. The root mean square deviation for all these systems is ∼9% which is excellent when compared with ∼50% obtained for predictions using the nondissociated composite molecule. Additionally, experimental LLE data has been collected for four ternary systems, namely: (a) 1‐ethyl‐3‐methylimidazolium ethylsulphate [Emim] [EtSO4] – Ethanol‐Hexene, (b) 1‐ethyl‐3‐methylimidazolium ethylsulphate [Emim] [EtSO4] – Ethanol‐Heptene, (c) 1,2‐dimethyl‐3‐ethylimidazolium ethylsulphate [E‐2,3‐dmim] [EtSO4] – Ethanol‐Hexene, and (d) 1,2‐dimethyl‐3‐ethylimidazolium ethylsulphate [E‐2,3‐dmim] [EtSO4] – Ethanol‐Heptene. The tie lines have been estimated using NMR and these have been compared with COSMO_LL predictions giving an average rmsd of ∼6%. © 2008 American Institute of Chemical Engineers AIChE J, 2008