The use of generalized cell-survival data in a physiologically based objective function for hyperthermia treatment planning: a sensitivity study with a simple tissue model implanted with an array of ferromagnetic thermoseeds

Thermoradiotherapy using interstitial self-regulating thermoseeds: an intermediate analysis of a phase II trial

OBJECTIVE

Thermoradiotherapy in the treatment of prostate cancer is based on a variety of experimental and clinical phase I data which have proven the synergistic effects of this combination. We report on a phase II trial in a special hyperthermia research group (SFB 273) of the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) to determine feasibility, acute toxicity and efficacy of this combination for prostate cancer.

METHODS

57 patients with localized prostate cancer were treated with interstitial hyperthermia using cobalt-palladium thermoseeds and conformal radiation between July 1997 and December 2000. Thermoseeds were placed into the prostate homogeneously. Hyperthermia was created using a magnetic field and was delivered in six sessions once weekly for one hour. 3D-conformal radiotherapy of 68.4Gy was given simultaneously in daily fractions of 1.8Gy.

RESULTS

Intraprostatic temperatures were between 42 and 46 degrees C. No major side effects were observed during hyperthermia. Median follow-up was 36 months (range 3-72 months). Median PSA value decreased from 11.6ng/ml to 2.4ng/ml 3 months after treatment, to 1.3ng/ml 12 months after treatment and to 0.55ng/ml 2 years after therapy.

CONCLUSION

Interstitial hyperthermia is feasible, well tolerated and led to a steep decrease of PSA values. Combining effective interstitial hyperthermia with conformal radiotherapy may be an exciting innovative treatment option for prostate cancer.

Interstitial hyperthermia using self-regulating thermoseeds combined with conformal radiation therapy

OBJECTIVE

The combination of hyperthermia and radiation in the treatment of malignancies is based on a variety of experimental data which have proven the synergistic effects of these two treatment modalities. We planned a phase II trial in a special hyperthermia research group (SFB 273) of the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) to determine feasibility, acute toxicity and efficacy of this combination for prostate cancer.

METHODS

A total of 57 patients with localized prostate cancer were treated with interstitial hyperthermia using cobalt-palladium thermoseeds and conformal radiation between July 1997 and December 2000. Thermoseeds were placed into the prostate homogeneously. Hyperthermia was created using a magnetic field and was delivered in six sessions once weekly. 3D-conformal radiotherapy of 68.4Gy was given simultaneously in daily fractions of 1.8Gy.

RESULTS

Intra-prostatic temperatures were between 42 and 46 degrees C. No major side effects were observed during hyperthermia. Median follow-up was 12 months (range: 3-26 months). Median prostate specific antigen (PSA) value decreased from 11.6 to 2.4 ng/ml 3 months after treatment, to 1.3ng/ml 12 months after treatment and to 0.55 ng/ml 2 years after the therapy.

CONCLUSION

Interstitial hyperthermia is feasible, well tolerated and led to a steep decrease of PSA values. Our current follow-up is too short to comment about efficacy. Combining effective interstitial hyperthermia with conformal radiotherapy may be an exciting innovative treatment option for prostate cancer.

Hyperthermia treatment planning

The development of hyperthermia, the treatment of tumours with elevated temperatures in the range of 40-44 degrees C with treatment times over 30 min, greatly benefits from the development of hyperthermia treatment planning. This review briefly describes the state of the art in hyperthermia technology, followed by an overview of the developments in hyperthermia treatment planning. It particularly highlights the significant problems encountered with heating realistic tissue volumes and shows how treatment planning can help in designing better heating technology. Hyperthermia treatment planning will ultimately provide information about the actual temperature distributions obtained and thus the tumour control probabilities to be expected. This will improve our understanding of the present clinical results of thermoradiotherapy and thermochemotherapy, and will greatly help both in optimizing clinical heating technology and in designing optimal clinical trials.