Management of Primary and Metastatic Renal Cell Carcinoma by Transcatheter Embolization With Iodine 125

The long-term results of the management of metastatic renal cell carcinoma by a radioactive interstitial implant seated by a transcatheter embolization technique were evaluated in 85 patients at risk at 2 years and 37 at 5 years. The 2-year survival rate was 33% and the 5-year survival rate was 32%. Patients with isolated skeletal metastases showed the best survival rate (2-year survival rate, 69%; 5-year survival rate, 60%). Isolated pulmonary, other parenchymal, and central nervous system (CNS) metastases showed a lower 2-year survival rate of 15%. Regardless of the site of metastases and the size of the primary, histologic grade appeared to have a substantial impact on the survival of our patients. The beneficial results of interstitial radiation therapy are attributed to reduction of tumor burden and possibly the stimulation of the host immune response that may initiate remission. The noticeably better results in patients with osseous metastases are attributed to the resolute treatment of all osseous metastases by additional interstitial iodine 125 (125I) infarct implants. Conversely, the poor results in patients with CNS and other parenchymal metastases may be based on the inability to treat such metastases with 125I interstitial infarct implants. In addition to clinical observations of weight gain and the cessation of pain and hematuria if present, remissions are heralded by normalization of the erythrocyte sedimentation rate, disappearance of tumor markers if present, and rise of beta interferon levels. The technique is advocated for the management of inoperable renal cell carcinoma with distant metastases.