[Intensity modulated radiotherapy treatment for prostate cancer, first experience in Chile]

Intensity modulated radiotherapy (IMRT) is an important step forward in cancer treatment.

To report the first experience in Chile with IMRT for prostate cancer and compare the results obtained with different doses.

From January 1997 through June 2008, 156 patients with a mean age of 70 years, were treated with radiotherapy and 121 with IMRT. Patients were staged according to American Commission on Cancer Staging. Their biochemical relapse risk was classified according to the MD Anderson classification. Patients were routinely checked during and after therapy to evaluate side effects and relapse.

Median follow up was 46 months (4-120). Overall five years survival was 85%. Biochemical relapse free five years survival for low, intermediate and high risk patients was 100, 82 and 70%, respectively. Biochemical relapse free survival for patients receiving radiotherapy doses over 76 Gy was 83%, compared to 30% for those receiving lower doses (p < 0.05). Urinary and gastrointestinal acute toxicity was low in 80% and 90% of patients respectively. Late toxicity developed in less than 3% of patients.

IMRT for prostate cancer is readily available and safe in Chile. Biochemical disease free survival improved with higher doses with low toxicity rates.