Niloy R Datta1, Dietmar Marder1, Sneha Datta2, Andreas Meister1, Emsad Puric1, Emanuel Stutz3, Susanne Rogers1, Brigitte Eberle1, Olaf Timm1, Michal Staruch1, Oliver Riesterer1,4, Stephan Bodis1,4. 1. Department of Radiation Oncology KSA-KSB, Kantonsspital Aarau, Aarau, Switzerland. 2. Animal Production and Health Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Department of Nuclear Sciences and Applications, International Atomic Energy Agency (IAEA), Vienna, Austria. 3. Department of Radiation Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland. 4. Department of Radiation Oncology, University Hospital Zurich, Switzerland.
Abstract
BACKGROUND: Thermal dose in clinical hyperthermia reported as cumulative equivalent minutes (CEM) at 43 °C (CEM43) and its variants are based on direct thermal cytotoxicity assuming Arrhenius 'break' at 43 °C. An alternative method centered on the actual time-temperature plot during each hyperthermia session and its prognostic feasibility is explored. METHODS AND MATERIALS: Patients with bladder cancer treated with weekly deep hyperthermia followed by radiotherapy were evaluated. From intravesical temperature (T) recordings obtained every 10 secs, the area under the curve (AUC) was computed for each session for T > 37 °C (AUC > 37 °C) and T ≥ 39 °C (AUC ≥ 39 °C). These along with CEM43, CEM43(>37 °C), CEM43(≥39 °C), Tmean, Tmin and Tmax were evaluated for bladder tumor control. RESULTS: Seventy-four hyperthermia sessions were delivered in 18 patients (median: 4 sessions/patient). Two patients failed in the bladder. For both individual and summated hyperthermia sessions, the Tmean, CEM43, CEM43(>37 °C), CEM43(≥39 °C), AUC > 37 °C and AUC ≥ 39 °C were significantly lower in patients who had a local relapse. Individual AUC ≥ 39 °C for patients with/without local bladder failure were 105.9 ± 58.3 °C-min and 177.9 ± 58.0 °C-min, respectively (p = 0.01). Corresponding summated AUC ≥ 39 °C were 423.7 ± 27.8 °C-min vs. 734.1 ± 194.6 °C-min (p < 0.001), respectively. The median AUC ≥ 39 °C for each hyperthermia session in patients with bladder tumor control was 190 °C-min. CONCLUSION: AUC ≥ 39 °C for each hyperthermia session represents the cumulative time-temperature distribution at clinically defined moderate hyperthermia in the range of 39 °C to 45 °C. It is a simple, mathematically computable parameter without any prior assumptions and appears to predict treatment outcome as evident from this study. However, its predictive ability as a thermal dose parameter merits further evaluation in a larger patient cohort.
BACKGROUND: Thermal dose in clinical hyperthermia reported as cumulative equivalent minutes (CEM) at 43 °C (CEM43) and its variants are based on direct thermal cytotoxicity assuming Arrhenius 'break' at 43 °C. An alternative method centered on the actual time-temperature plot during each hyperthermia session and its prognostic feasibility is explored. METHODS AND MATERIALS: Patients with bladder cancer treated with weekly deep hyperthermia followed by radiotherapy were evaluated. From intravesical temperature (T) recordings obtained every 10 secs, the area under the curve (AUC) was computed for each session for T > 37 °C (AUC > 37 °C) and T ≥ 39 °C (AUC ≥ 39 °C). These along with CEM43, CEM43(>37 °C), CEM43(≥39 °C), Tmean, Tmin and Tmax were evaluated for bladder tumor control. RESULTS: Seventy-four hyperthermia sessions were delivered in 18 patients (median: 4 sessions/patient). Two patients failed in the bladder. For both individual and summated hyperthermia sessions, the Tmean, CEM43, CEM43(>37 °C), CEM43(≥39 °C), AUC > 37 °C and AUC ≥ 39 °C were significantly lower in patients who had a local relapse. Individual AUC ≥ 39 °C for patients with/without local bladder failure were 105.9 ± 58.3 °C-min and 177.9 ± 58.0 °C-min, respectively (p = 0.01). Corresponding summated AUC ≥ 39 °C were 423.7 ± 27.8 °C-min vs. 734.1 ± 194.6 °C-min (p < 0.001), respectively. The median AUC ≥ 39 °C for each hyperthermia session in patients with bladder tumor control was 190 °C-min. CONCLUSION: AUC ≥ 39 °C for each hyperthermia session represents the cumulative time-temperature distribution at clinically defined moderate hyperthermia in the range of 39 °C to 45 °C. It is a simple, mathematically computable parameter without any prior assumptions and appears to predict treatment outcome as evident from this study. However, its predictive ability as a thermal dose parameter merits further evaluation in a larger patient cohort.
Entities:
Keywords:
AUC; CEM; Thermal dose; area under the curve; hyperthermia; thermometry
Authors: Adela Ademaj; Danai P Veltsista; Pirus Ghadjar; Dietmar Marder; Eva Oberacker; Oliver J Ott; Peter Wust; Emsad Puric; Roger A Hälg; Susanne Rogers; Stephan Bodis; Rainer Fietkau; Hans Crezee; Oliver Riesterer Journal: Cancers (Basel) Date: 2022-01-26 Impact factor: 6.639
Authors: Ioannis Androulakis; Rob M C Mestrom; Miranda E M C Christianen; Inger-Karine K Kolkman-Deurloo; Gerard C van Rhoon Journal: Cancers (Basel) Date: 2022-03-10 Impact factor: 6.639