Comparison between two ¹²⁵I brachtyerapy implant techniques; preplanning and intraoperative method: Dose escalation deteriorate acute morbidity?

We compared two world-widely used permanent ¹²⁵T seed implant techniques : preplanning and intraoperative planning, based on post-implant dosimetry and acute toxicity. We reported results of a detailed post-implant dosimetric evaluation and comparison of acute toxicities between 122 consecutive patients with prostate adenocarcinoma treated by the preplanning methodology and 122 patients treated with the intraoperative, interactive seed implant method according to Mount Sinai Medical Center. Baseline parameters were similar in both groups. On day 30 post-implant CT, mean D90, expressed as minimal dose covering 90% of the gland volume was 155Gy for the preplanned group and 172Gy for the intraoperative group (P<0.01). Based on day 1 and 30 post-implant CT, most of urethral and rectal dosimetric parameters were similar between two groups. Acute morbidity, assessed by the Common Terminology Criteria for Adverse Events v3.0, was minimal in both groups and did not correlate with the technique employed. This comparison of implant adequacy favors this particular intraoperative method. While dose parameters of prostate was significantly better with the intraoperative method, no increased short-term morbidity was noted. Longer-term clinical outcome should substantiate our contention of the superiority of the intraoperative method.