Local hyperthermia combined with external irradiation for regional recurrent breast carcinoma

Backgrounds

The purpose of this study was to evaluate the therapeutic effects of hyperthermia in combination with radiotherapy for locoregional recurrence of breast cancer, and to assess the factors related to subsequent local tumor control.

Methods

Between March 1981 and February 2001, 85 lesions in 73 patients were treated with local hyperthermia combined with external irradiation. Of 75 evaluable lesions, 41 were previously irradiated. Mean radiation dose to the previously unirradiated area was 59.5 ± 6.8 Gy (range, 40–70 Gy), while a total dose of 43.0 ± 12.4 Gy (range, 12–74.4 Gy) was administered to previously irradiated tumors. Hyperthermia was administered once or twice per week. The average number of hyperthermia sessions was 4.5 (2–9).

Results

Complete responses (CRs) were achieved in 56% (23/41) of previously irradiated and 47% (16/34) of unirradiated tumors. There was no significant difference in the CR rate between the two groups. Compared with the response of bulky/nodular tumors, diffuse/multiple small nodular tumors showed a higher CR rate at 4 weeks after treatment. However, at 6 months after treatment, they showed a significantly lower local control rate.

Conclusions

The present findings suggested a significant benefit of local hyperthermia combined with radiotherapy in the treatment of locally recurrent breast cancer, especially for previously irradiated recurrence, by reducing the total irradiation dose. Diffuse/multiple small nodular tumors respond earlier than bulky/large nodular tumors; however, they tend to recur within the treatment field.