[The intraoperative radiotherapy (IORT) of locally spread and recurrent renal-cell carcinomas].

PURPOSE

Renal cell carcinomas are relatively radioresistant. After macroscopically incomplete tumor resection conventional external beam radiotherapy is dose-limited and additional systemic treatment with chemotherapy ineffective to achieve local control. In a pilot study the role of intraoperative radiotherapy in the treatment of locally advanced or recurrent renal cell carcinomas was analysed.

PATIENTS AND METHODS

From January 1992 to July 1994 11 patients with a primary (n = 3) or recurrent renal cell carcinoma had IORT. One patient had complete resection and in 3 respectively 7 patients microscopically or macroscopically residual disease was left. Using 6 to 10 MeV, a single dose of 15 to 20 Gy was delivered to the fossa renalis and the corresponding paraaortic area. Based on three-dimensional treatment planning, additional external beam radiotherapy was given 3 to 4 weeks later (40 Gy, 2 Gy SD, 23 MV).

RESULTS

After a mean follow-up of 24.3 months 5 patients had died of distant metastases (lung, liver, bone, mediastinum) with a mean survival time of 11.5 months. Mean disease-free interval was 6.4 months. One patient suffered from a second malignancy. Two patients are alive with distant metastases. Local tumor control in the entire group was 100%. The calculated 4-year overall and disease-free survival was 47% and 34%. The postoperative course was affected in 3 patients (abscess n = 1, short dehiscence of the abdominal wound n = 2). The gastrointestinal toxicity during external beam radiotherapy was low. No IORT-specific late adverse effects were observed.

CONCLUSION

After incomplete tumor resection local tumor control with minimal therapy related side effects could be achieved using intraoperative radiotherapy. With IORT the dose limitation in the radiotherapy of renal cell carcinoma could be overcome. The high distant metastases rate relativized overall prognosis. The low morbidity rate justifies further evaluation of this technique.