Adjuvant pelvic hyperthermia in advanced cervical carcinoma. I. Feasibility, thermometry and device comparison

From 1981 to 1989, a total of 26 women with locally or regionally advanced carcinoma of the uterine cervix were treated with radiotherapy (RT) and pelvic regional hyperthermia (HT), in the Divisions of Radiation Oncology at the University of Utah Medical Center (UU) and the Kenneth Norris Jr Cancer Hospital of the University of Southern California (USC). HT was produced by the BSD-1000 HT system and the annular phased array (AA) applicator usually driven at 60-65 MHz, or the BSD-2000 HT system and the Sigma-60 (S60) applicator usually driven at 70-85 MHz. During the HT sessions acute toxicity was common, particularly because of pain within or outside the applicator, which was power-limiting in 43% of the patients overall. Pain was more easily manipulated, but more commonly power-limiting with the S60. Systemic stress was power-limiting in 22% of patients treated with the AA, but in no patients with the S60. Detailed thermal mapping and temperature analysis were performed on 26 patients. The mean overall average intratumour temperature achieved was 41 +/- 1.1 degrees C for 30 min; 5% and 35% of the monitored intratumour loci exceeded 43 degrees C and 42 degrees C, respectively. Temperatures recorded in the cervical os and proximal vagina appeared lower relative to the monitored normal structures in the region. Subacute treatment related toxicities occurred in five patients and included protracted pain (three) and superficial second degree burns (one), all of which resolved with supportive non-surgical therapy.