Purpose: We determined prostate perfusion in 18 patients with locally advanced prostate carcinoma treated with a combination of external beam irradiation and regional (10) or interstitial (8) hyperthermia.
Materials and methods: Perfusion values were calculated from temperature elevations due to constant applied power and from transient temperature measurements after a change in applied power. Student's t test was used for comparing perfusion values with time and in the 2 groups.
Results: At the start of regional hyperthermia treatment mean estimated perfusion plus or minus standard deviation was 10 +/- 8 ml./100 gm. per minute. At the end of treatment mean perfusion was increased to 14 +/- 2 ml./100 gm. per minute (p <0.01). Achieved thermal parameters were a mean temperature of at least 40.3C +/- 0.6C in 90% of the prostate, 40.9C +/- 0.6C in 50% and a mean maximum temperature of 41.6C +/- 0.6C. At the end of interstitial hyperthermia treatment estimated mean perfusion was 47 +/- 5 ml./100 gm. per minute, which was significantly different compared with the end of regional hyperthermia (p < 0(-7) ). Mean temperature was at least 39.4C +/- 0.9C in 90% of the prostate and 41.8C +/- 1.6C in 50%, while mean maximum temperature was 53.1C +/- 6.3C. Systemic temperature increased during regional hyperthermia up to 38.6C, whereas during interstitial hyperthermia body temperature was not elevated.
Conclusions: During interstitial hyperthermia perfusion values are higher than during regional hyperthermia. Hyperthermia causes increased prostate perfusion.