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Session: Optimising outcome in cervix BT OC-1047: Dose to vaginal wall in cervical cancer brachytherapy and associated morbidity M. Serban, A.A.C. De Leeuw, K. Tanderup, I.M. Jürgenliemk-Schulz. [Extracted from the article]

Proffered Papers: Proffered papers 28: Gynaecology OC-0566: Risk factors for nodal failure in the EMBRACE study cohort M. Peters, A.A.C. De Leeuw, R. Pötter, C.N. Nomden, K. Tanderup, K. Kirchheiner, M.P. Schmid, I. Fortin, C. Haie-Meder, J.C. Lindegaard, A. Sturdza, U. Mahantshetty, P. Hoskin, B. Segedin, K. Bruheim, B. Rai, F. Huang, R. Cooper, E. Van der Steen-Banasik, E. Van Limbergen, R. Nout, I. Jürgenliemk-Schulz. [Extracted from the article]

To report an interim clinical evaluation of combined external beam irradiation (EBRT) and interstitial or regional hyperthermia in the treatment of locally advanced prostate cancer. From 1997 to 2001, 26 patients with T3-4/NX/0M0 prostate carcinoma were treated with a combination of conformal EBRT and hyperthermia. Fourteen patients received five weekly regional hyperthermia treatments within an optimization (phase II) study, using the coaxial transverse electrical magnetic system. Twelve patients received one interstitial hyperthermia treatment within a feasibility study (phase I), using the multi-electrode current source system. Irradiation was delivered using a conformal three-field technique, administering 70 Gy in 2-Gy fractions in 7 weeks. The mean initial prostate-specific antigen level was 26 ng/mL. Three patients had a T4 and 23 a T3 tumour; the tumours were classified as well (four), moderately (16) and poorly (six) differentiated. The mean follow-up was 36 months. In the combined treatments there was no toxicity of more than grade 2. In regional hyperthermia the mean index temperature (T90 and T50, i.e. exceeded by 90% and 50% of the measurements) was 40.2 °C and 40.8 °C, and for interstitial hyperthermia 39.4 °C and 41.8 °C, respectively. All patients survived; seven patients had a biochemical relapse (27%), three in the regional and four in the interstitial group. The actuarial probability of freedom from biochemical relapse was 70% at 36 months for all patients together, 79% for regional and 57% for interstitial. No factors were found that could be used to predict relapse. The clinical outcome in these patients with advanced localized prostate cancer seems to compare favourably with most series using irradiation alone, and the treatment caused no severe complications. [ABSTRACT FROM AUTHOR]

Capacitively coupled hyperthermia devices are widely in use, mainly in Asian countries. In this paper, a comprehensive treatment planning system, including a Specific Absorption Rate (SAR) and thermal model for capacitively coupled hyperthermia, is described and demonstrated using a heterogeneous patient model. In order to accurately model a hyperthermia treatment, simulation at high resolution is mandatory. Using the quasi-static approximation, the electromagnetic problem can be solved at high resolution with acceptable computational effort. The validity of the quasi-static approximation is demonstrated by comparing the Maxwell solution of a phantom problem to the quasi-static approximation. Modelling of capacitive hyperthermia of the prostate reveals the difficulty of heating deep-seated tumours in the pelvic area. Comparison of the SAR distribution in the heterogeneous patient model and a patient shaped agar phantom shows a shielding effect of the pelvic bone and the influence of the fat-muscle distribution. It is shown that evaluation of capacitive hyperthermia with agar phantoms leads to overly optimistic conclusions. Therapeutic relevant tumour temperatures can only be obtained by permitting temperature extrema in normal tissue. This concurs with clinical practice, where treatment-limiting hot spots restrict the tumour temperature. It is demonstrated that the use of very cold overlay bolus bags has only a very superficial effect. The presented model can be used for individual treatment planning and optimization, for the evaluation of capacitive applicator modifications and comparison with other devices. [ABSTRACT FROM AUTHOR]

Session: Optimising outcome in cervix BT OC-1051: Local failure in cervical cancer patients after MR image-guided adaptive brachytherapy M. Schmid, C. Kirisits, K. Tanderup, C. Haie-Meder, L. Fokdal, A. Sturdza, P. Hoskin, U. Mahantshetty, B. Segedin, K. Bruheim, F. Huang, B. Rai, R. Cooper, E. Van der Steen-Banasik, E. Van Limbergen, B. Pieters, L.T. Tan, R. Nout, A.A.C. De Leeuw, N. Nesvacil, I. Jürgenliemk-Schulz, J.C. Lindegaard, R. Pötter, E. Collaborative Group. [Extracted from the article]