Several studies compare LDR BT as SCH772984 order standard treatment vs. HDR BT, with some contradictive results. A recent meta-analysis pooled the results of randomized studies and concludes no significant differences for survival and LC (19). In interpreting these results, it is necessary to keep in mind the range of radiation and BT technologies
used in these studies. PDR seems to be a good compromise between LDR and HDR with radiobiologic advantages of LDR and technical advantages of HDR. Only one prospective study has compared continuous LDR BT and PDR BT for cervical carcinoma: 166 patients were analyzed prospectively, 57 in the PDR BT arm. The dose rate was similar in both groups (66 cGy/h in LDR and 70 cGy/h in PDR arm). No differences were found for severe late toxicity. The actuarial 3-year OS rate was 75% for both groups, with no significant differences in 3-year DFS for the PDR BT group (70% vs. 57%, p = 0.19) (20). Only one randomized prospective study suggests the impact of LDR variations (21), with 204 patients with Stage I and limited Stage II cervical cancer randomized to receive one of two preoperative BT LDRs (0.4 and 0.8 Gy/h). The investigators reported a greater late complications rate with
higher dose rate (38 cGy/h vs. 73 cGy/h), with no impact on survival. Our results do not support this finding as we find a low complication rate with a median dose rate of 65 cGy/h: 2.6% of gastrointestinal tract complications, this website 4.4% urinary tract severe toxicity, and 1.3% complete obliteration of the vagina. These toxicity rates were in accordance with those established with LDR. In the review by Barillot et al. (22), 4% of late severe urinary toxicity and 2–4% of gastrointestinal oxyclozanide tractus (35% for locally advanced cancer) were established. We acknowledge the limitations of this study owing to its retrospective assessment of toxicity; however,
with 50.6% Grades 1 and 2 late vaginal effects, our rate is less than that reported by Potter et al. (23) in a large series of HDR BT (78%). In the multivariate analyses on outcomes, classical clinical factors such as negative nodal involvement are correlated with the 5-year LC but also the use of 3D-based planning BT. Interest in BT 3D imaging planning has increased and represents currently one of the most important developments in gynecologic BT. Recently, guidelines have been published by the GEC ESTRO  and . However, up until now, limited clinical evidence has been published demonstrating the impact of 3D BT. Chargari et al. (25) have been the first to report their experience with MRI-based intracavitary PDR BT so far, for 45 patients with locally advanced cervical carcinoma. The 2-year OS was 78% without any Grade 4 toxicity and with only one Grade 3 toxicity with a vesicovaginal fistula.