Clinical implementation of hyperthermia treatment planning guided steering: A cross over trial to assess its current contribution to treatment quality

Purpose: To assess the current feasibility of online hyperthermia treatment planning guided steering (HGS) and its current contribution to treatment quality in deep hyperthermia for locally advanced cervical cancer. Materials and methods: 36 patients were randomized to receive either their second and fourth (arm A) or their third and fifth (arm B) hyperthermia treatment of the series with the aid of HGS. The other treatments were conducted according to the Rotterdam Empirical Steering Guidelines (RESG). Results: During period I (second and third treatment of the series) similar results were found for HGS and RESG with a slight, non-significant difference found in favour of HGS. The average temperature T50 was 40.3 degrees C for both (p = 0.409) and the dose parameter CEM43T90 was 0.64 for RESG and 0.63 for HGS (p = 0.154). However, during period II (fourth and fifth treatment of the series) HGS performed less well, with significant lower thermal dose parameters, minimum, mean and maximum intraluminal temperatures, tolerance measures and net integrated power. T50 was 40.4 degrees C after RESG and 40 degrees C after HGS (p = 0.001) and CEM43T90 0.57 and 0.38 (p = 0.01) respectively. Conclusion: We found that the procedure of online treatment planning guided steering is feasible. For maximal exploitation of its possibilities, however, better control and understanding of several patient, tumour and technical parameters is required. This study has been very helpful in identifying some of the challenges and flaws that warrant further investigation in the near future, such as patient positioning and the prevention of hotspot-related complaints.