Radiotherapy for Renal Cell Carcinoma:
Although classic dogma considers renal cell carcinoma (RCC) to be a “radiation resistant” lesion, comprehensive literature review clouds this issue, with a wide variety of response rates to radiotherapy reported
In the treatment of primary kidney tumors, radiotherapy has been used as a preoperative or postoperative surgical adjuvant, but has not gained wide acceptance in either scenario due to toxicity and questionable effectiveness. More contemporary literature describing three-dimensional conformal radiotherapy again suggests benefit with post-operative adjuvant radiotherapy in high-risk RCC patients, such as those whose tumor extends beyond the kidney or extends to involve the surgical margin. Radiotherapy by itself has not been used in the primary curative treatment of RCC, due to the perceived or actual radiation resistance of RCC lesions, and the exquisite sensitivity of adjacent normal kidney and gastrointestinal tissue to radiation, which has limited the applied dose to a sub-curative level when conventional radiation techniques have been used.
The larger experience with radiotherapy for RCC has been gained against symptomatic metastatic disease (RCC tumor deposits that have spread to other parts of the body), where there seems to be a dichotomy of reported responses. A high frequency of favorable responses against painful bone metastatic RCC lesions has been reported by multiple authors , whereas uniformly dismal results have been reported for conventional radiotherapy for RCC metastatic to the brain . In the treatment of metastatic disease, there remains uncertainty as to the appropriateness of the term “radioresistant,” as some authors have described a dose response curve favoring higher dose doses . |
