Urano M, Tanaka N
Department of Radiation Medicine, Massachusetts General Hospital, Boston 02114.
Int J Hyperthermia. 1989 Sep-Oct;5(5):617-24. doi: 10.3109/02656738909140485.
The effect of pretransplantation irradiation of tumour beds (tumour bed effect or TBE) on the response of tumours to elevated temperatures and on the kinetics of thermo-tolerance was studied. Animal tumours were early generation isotransplants of a fibro-sarcoma, FSa-II in C3Hf/Sed mice. The tumour bed or murine foot was irradiated with 0.8 or 16 Gy in air, and tumour cell suspensions were transplanted 1-35 days thereafter. Hyperthermia of various durations was given in a 45.5 degrees C water bath when tumours reached an average diameter of 6 mm (110 mm3), and the tumour growth (TG) time to reach 500 mm3 was obtained. Dose-response curves between the TG time and the treatment time were less steep for tumours in preirradiated tumour beds than for tumours in non-irradiated tumour beds, indicating that the tumours in preirradiated tumour beds were more resistant to hyperthermia compared to the tumours in normal tumour beds. This resistance appeared to increase with increasing preirradiation dose. Thermotolerance was equally developed in tumours in normal and preirradiated tumour beds. The time required to develop the maximum thermotolerance was identical for both tumours. This indicated that the TBE has no effect on the kinetics of thermotolerance. The implication of these results in clinical trials may be that the tumour which recurred after radiotherapy may not be a good candidate for hyperthermia.
研究了肿瘤床的移植前照射（肿瘤床效应或TBE）对肿瘤对高温反应及热耐受动力学的影响。动物肿瘤为C3Hf/Sed小鼠体内纤维肉瘤FSa-II的早期同基因移植瘤。肿瘤床或小鼠足部在空气中接受0.8或16 Gy照射，此后1 - 35天移植肿瘤细胞悬液。当肿瘤平均直径达到6 mm（110 mm3）时，在45.5℃水浴中给予不同时长的热疗，并记录肿瘤生长（TG）至500 mm3的时间。与未照射肿瘤床中的肿瘤相比，照射过的肿瘤床中的肿瘤，其TG时间与治疗时间之间的剂量反应曲线较平缓，这表明照射过的肿瘤床中的肿瘤比正常肿瘤床中的肿瘤对热疗更具抗性。这种抗性似乎随着照射前剂量的增加而增强。正常和照射过的肿瘤床中的肿瘤热耐受程度相同。两种肿瘤达到最大热耐受所需的时间相同。这表明肿瘤床效应不影响热耐受动力学。这些结果在临床试验中的意义可能是，放疗后复发的肿瘤可能不是热疗的理想对象。
