Since September 1983, five patients with head and
neck cancers and five patients with pelvic or perineal recurrences of
colorectal neoplasms received 192Ir interstitial implants through flexible afterloading
catheters that were modified to allow RF
hyperthermia treatments of the
tumor within 1 hr pre- and post-
brachytherapy. Local control in the implant volume was obtained in three of the patients with head and
neck cancers (base tongue--2/4; floor of mouth--1/1) with follow-up of 9 to 42 months. Two patients had local recurrences after disease-free periods of 8 and 24 months. Two of the five patients treated for pelvic recurrences had complete responses lasting less than 3 months; prolonged stabilization (12 months) of a presacral mass in a third patient also occurred, but the
neoplasm eventually regrew. Average temperatures of 39.2 degrees C to 43.7 degrees C were obtained in the implant volumes of these patients during the 45 minute heating periods which took place prior to loading, and just after removal, of the 192Ir seeds in each patient. No instances of intra or post-operative
hemorrhage or
necrosis of bone or soft tissues occurred in these patients. However, one individual required a permanent
tracheostomy for persistent epiglottic
edema after implantation as part of a base-tongue
brachytherapy procedure. Interstitial RF
hyperthermia in conjunction with
brachytherapy appears to be a relatively safe and effective modality, but must be tested prospectively to compare its efficacy to interstitial irradiation alone.