Carbon Ion Radiotherapy For Renal Cell Carcinoma: Outcome Of A Pilot Study

Purpose/Objective(s)Renal cell carcinoma (RCC) is one of the radioresistant tumors, and definitive radiotherapy for RCC has not been established. We evaluated the outcomes of patients with RCC who had been treated with carbon ion radiotherapy.Materials/MethodsData for patients with RCC who had received the carbon ion radiotherapy at our institution were analyzed. Clinical stage was determined based on TNM classification (UICC), and adverse events were determined based on CTCAE ver. 3.0. Local recurrence was defined as definite tumor regrowth after treatment. From the first date of treatment, local control rate (LCR), progression-free survival (PFS), cause-specific survival (CSS) and overall survival (OS) were calculated.ResultsFrom the first patient in 1997, all 10 patients with RCC completed the carbon ion radiotherapy, and data for these patients were included in analyses. There were 7 stage I patients and 3 stage IV (T4 or N2) patients, but none of the patients had distant metastasis (M0). The median maximum diameter of the tumor was 43 mm (24–120 mm) and the median volume of the tumor was 38 cc (6–509 cc). Nine patients with histologically proven RCC and one clinically diagnosed patient were treated with median total dose of 72 GyE (gray equivalents, range: 64–80 GyE) in 16 fractions. Median follow-up period was 46.3 months (5–111 months). Five-year LCR, 5-year PFS, 5-year CSS and 5-year OS were 100%, 100%, 100% and 74%, respectively. Two intercurrent deaths without recurrence were observed, Interestingly, treated tumors showed very slow shrinkage, and the tumor in one case has been shrinking for 11 years. One patient with muscular invasion (T4 tumor) developed grade 4 skin toxicty, but no other toxicity greater than grade 2 was observed.ConclusionsThis seems to be the first report on carbon ion radiotherapy for RCC, and the response of the tumor to treatment was unusual. Despite inclusion of T4 and massive tumors, 5-year LCR and 5-year CSS were both 100%. The results indicated the possibiloity of carbon ion radiotherapy becoming a new curative treatment for RCC. Purpose/Objective(s)Renal cell carcinoma (RCC) is one of the radioresistant tumors, and definitive radiotherapy for RCC has not been established. We evaluated the outcomes of patients with RCC who had been treated with carbon ion radiotherapy. Renal cell carcinoma (RCC) is one of the radioresistant tumors, and definitive radiotherapy for RCC has not been established. We evaluated the outcomes of patients with RCC who had been treated with carbon ion radiotherapy. Materials/MethodsData for patients with RCC who had received the carbon ion radiotherapy at our institution were analyzed. Clinical stage was determined based on TNM classification (UICC), and adverse events were determined based on CTCAE ver. 3.0. Local recurrence was defined as definite tumor regrowth after treatment. From the first date of treatment, local control rate (LCR), progression-free survival (PFS), cause-specific survival (CSS) and overall survival (OS) were calculated. Data for patients with RCC who had received the carbon ion radiotherapy at our institution were analyzed. Clinical stage was determined based on TNM classification (UICC), and adverse events were determined based on CTCAE ver. 3.0. Local recurrence was defined as definite tumor regrowth after treatment. From the first date of treatment, local control rate (LCR), progression-free survival (PFS), cause-specific survival (CSS) and overall survival (OS) were calculated. ResultsFrom the first patient in 1997, all 10 patients with RCC completed the carbon ion radiotherapy, and data for these patients were included in analyses. There were 7 stage I patients and 3 stage IV (T4 or N2) patients, but none of the patients had distant metastasis (M0). The median maximum diameter of the tumor was 43 mm (24–120 mm) and the median volume of the tumor was 38 cc (6–509 cc). Nine patients with histologically proven RCC and one clinically diagnosed patient were treated with median total dose of 72 GyE (gray equivalents, range: 64–80 GyE) in 16 fractions. Median follow-up period was 46.3 months (5–111 months). Five-year LCR, 5-year PFS, 5-year CSS and 5-year OS were 100%, 100%, 100% and 74%, respectively. Two intercurrent deaths without recurrence were observed, Interestingly, treated tumors showed very slow shrinkage, and the tumor in one case has been shrinking for 11 years. One patient with muscular invasion (T4 tumor) developed grade 4 skin toxicty, but no other toxicity greater than grade 2 was observed. From the first patient in 1997, all 10 patients with RCC completed the carbon ion radiotherapy, and data for these patients were included in analyses. There were 7 stage I patients and 3 stage IV (T4 or N2) patients, but none of the patients had distant metastasis (M0). The median maximum diameter of the tumor was 43 mm (24–120 mm) and the median volume of the tumor was 38 cc (6–509 cc). Nine patients with histologically proven RCC and one clinically diagnosed patient were treated with median total dose of 72 GyE (gray equivalents, range: 64–80 GyE) in 16 fractions. Median follow-up period was 46.3 months (5–111 months). Five-year LCR, 5-year PFS, 5-year CSS and 5-year OS were 100%, 100%, 100% and 74%, respectively. Two intercurrent deaths without recurrence were observed, Interestingly, treated tumors showed very slow shrinkage, and the tumor in one case has been shrinking for 11 years. One patient with muscular invasion (T4 tumor) developed grade 4 skin toxicty, but no other toxicity greater than grade 2 was observed. ConclusionsThis seems to be the first report on carbon ion radiotherapy for RCC, and the response of the tumor to treatment was unusual. Despite inclusion of T4 and massive tumors, 5-year LCR and 5-year CSS were both 100%. The results indicated the possibiloity of carbon ion radiotherapy becoming a new curative treatment for RCC. This seems to be the first report on carbon ion radiotherapy for RCC, and the response of the tumor to treatment was unusual. Despite inclusion of T4 and massive tumors, 5-year LCR and 5-year CSS were both 100%. The results indicated the possibiloity of carbon ion radiotherapy becoming a new curative treatment for RCC.