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Objective: To illustrate the wider potential scope of image-guided intensity-modulated radiotherapy (IG-IMRT), outside of the "standard" indications for IMRT. Methods: Nine challenging clinical cases were selected. All were treated with radical intent, although it was accepted that in several of the cases the probability of cure was low. IMRT alone was not adequate owing to the close proximity of the target to organs at risk, the risk of geographical miss, or the need to tighten planning margins, making image-guided radiotherapy an essential integral part of the treatment. Discrepancies between the initial planning scan and the daily on-treatment megavoltage CT were recorded for each case. The three-dimensional displacement was compared with the margin used to create the planning target volume (Ply). Results: All but one patient achieved local control. Three patients developed metastatic disease but benefited from good local palliation; two have since died. A further patient died of an unrelated condition. Four patients are alive and well. Toxicity was low in all cases. Without daily image guidance, the Ply margin would have been insufficient to ensure complete coverage in 49% of fractions. It was inadequate by >3mm in 19% of fractions, and by >5mm in 9%. Conclusion: IG-IMRT ensures accurate dose delivery to treat the target and avoid critical structures, acting as daily quality assurance for the delivery of complex IMRT plans. These patients could not have been adequately treated without image guidance. Advances in knowledge: IG-IMRT can offer improved outcomes in less common clinical situations, where conventional techniques would provide suboptimal treatment. [ABSTRACT FROM AUTHOR]

Objectives The aims of this study are to assess the extent of ovarian movement on consecutive MRI examinations in patients with gynaecological malignancies and to define potential safety volumes around the ovaries that may avoid ovarian ablation during pelvic irradiation. Methods Patients with cervical, vaginal and endometrial cancer who underwent MRI examinations of the pelvis before and during radiotherapy were included in the study. The position of the ovaries was retrospectively determined on two consecutive axial and sagittal T2 weighted MRI examinations of the pelvis. Ovarian movement was determined in craniocaudal, anteroposterior and mediolateral directions. Safety volumes were calculated by computing elliptical volumes based on the derived 95% and 99% reference intervals. Results 30 patients with a gynaecological malignancy were included. Both ovaries could be identified on the MRI examinations in all cases. The safety volumes around the ovaries encompassing 95% and 99% of ovarian movement were 11 and 25 cm3 (95%), and 24 and 54 cm3 (99%), for the left and right ovary, respectively. Conclusion Adding a safety volume around the ovaries may reduce the high radiation dose to the ovaries. This could potentially avoid ovarian ablation, reducing significant fertility morbidity. [ABSTRACT FROM AUTHOR]