K. Shiraishi

Esophageal cancer: definitive chemoradiotherapy for elderly patients

To investigate the efficacy and toxicity of definitive chemoradiotherapy (CRT) for elderly patients with locally advanced esophageal cancer. Twenty-two patients aged over 75 that performed definitive CRT were retrospectively reviewed. The regimen included concurrent CRT consisting of two cycles of chemotherapy (CTx) of platinum and 5-fluorouracil, and radiation therapy (RT) of 50-50.4 Gy (actual range: 45.4-71.4 Gy), and additional CTx where possible. Both CTx and RT were reduced in dose and field where necessary. The disease-free survival rate and the overall survival rate at 3 years were 33.3% ± 11.4% and 25.9% ± 10.8%. Grade 4 leukocytopenia and thrombocytopenia occurred in three (14%) and four (18%) patients. Treatment-related death was suspected in up to four (18%) patients at the most. Univariate analyses for disease-free survival showed that neither total radiation dose nor number of total cycles of CTx was significant. The pattern of relapse was predominantly more frequent in the intra-RT field than outside the RT field. For elderly patients, adverse events are frequent, and decreased organ reserve may cause treatment-related death. Reduction in CTx dose or RT field, appropriate only for two cycles of CTx, and careful monitoring may help to minimize toxicity. Physicians should not be too afraid of adverse events or be negative about CRT for elderly patients, as long as comorbidities and complications are managed carefully.

Small bowel perforation without tumor recurrence after radiotherapy for cervical carcinoma: Report of seven cases

Aim:  We describe the clinical presentation, evaluation, management and outcome of patients experiencing small bowel perforation following radiation therapy for cervical cancer.

Dose verification of intensity-modulated arc therapy using an ERGO++ treatment planning system and Elekta internal multileaf collimators for prostate cancer treatment

Dose verification of intensity-modulated arc therapy using an ERGO++ treatment planning system and Elekta internal multileaf collimators is described. Prostate intensity-modulated arc therapy was planned using the arc modulation optimization algorithm inverse planning module of ERGO++. After transferring the plan to Elekta Synergys controller (Elekta Ltd, Crawley, UK), the isocentre dose was measured and compared with a calculated dose using a pinpoint chamber and a water phantom in a cylindrical acrylic enclosure. Subsequently, an EDR2 film was placed inside a multilayer plastic phantom, and total dose distributions were measured in three axial planes as well as in the coronal and sagittal planes to compare the actual dose with the calculated dose. The dose discrepancy at the isocentre was 1.7%. The calculated gamma indices were less than 1 over 90% of the three axial planes, as well as in the coronal and sagittal planes, having a dose greater than 50% of the maximum target dose.

PO-0798: Scattering contributions in out-of-field dosimetry using Monte Carlo calculation for breast conserving therapy

hight dose gradient regions. This same was made in 7 clinical plans. Also, 2 plans in validation and 8 plans in clinical practice were recalculated in an alternative phantom due to geometric uncertainties. Conclusions: The agreement between measurements and Diamond may be interpreted as an absence of systematic errors. In the same way the comparison between Eclipse and Diamond produced very similar results. One year experience shows results very close to those obtained in validation. This agreement led us to consider Diamond a valuable tool for QA in VMAT plans.

PO-0729: Development of late toxicity treated with image-guided volumetric modulated arc therapy for prostate cancer

PO-0726 Rotational optimization appears undeferrable in IGRT prostate: first analysis of the Protura 6DOF robotic couchtop V. Frascino, S. Chiesa, L. Placidi, L. Azario, G.C. Mattiucci, F. De Rose, V. Valentini, M. Balducci Università Cattolica del Sacro Cuore, Department of Radiotherapy and Radio-Oncology, Rome, Italy Università Cattolica del Sacro Cuore, Institute of Medical Physics, Rome, Italy