Evidence behind use of intensity-modulated radiotherapy: a systematic review of comparative clinical studies

IMRT and IGRT in head and neck cancer: Have we delivered what we promised?

“…The promise of generating highly conformal and concave dose distributions around complex target volumes with steep dose-gradients makes IMRT ideally suited to HNC. 6,12,13 The tolerance of surrounding organs at risk (OARs) is generally lesser than the prescription dose, which can be safely delivered with image-guided IMRT without compromising target volume coverage. The promise to reduce acute and late morbidity of treatment in conjunction with comparable or even better locoregional control and a potential positive impact on qua- lity-of-life (QOL) and survival has prompted widespread adoption of IMRT and IGRT.…”

“…However, the key question whether that dosimetric advantage translates into a significant and meaningful clinical benefit remains unanswered. 13 The correlation of dosimetric parameters with organ function and toxicity has generated robust and valuable dosevolume-toxicity relationship. These dose-volume constraints are now routinely applied as objectives in IMRT optimization to reduce OAR to acceptable levels.…”

“…The contemporary practice of head neck IMRT has largely evolved from single-institution phase I-II prospective studies 13 consistently demonstrating either comparable or even favorable outcomes in cancers arising both from unspecified head-neck sites [17][18][19][20][21][22] (Table 1) Table 2). The Kaplan-Meier estimates of loco-regional control at 2-to 4-years has varied from 80-100% across these studies (excepting for oral cavity) which is certainly not inferior (either comparable or even superior) to historical controls with similar stage disease treated with conventional techniques.…”

Dosimetric impact of different multileaf collimators on prostate intensity modulated treatment planning

“…The clinical evidence for the effectiveness of IMRT is encouraging. 1 IMRT treatment delivery requires the use of multileaf collimators (MLC). Over the years, linear accelerator vendors have not only improved the reliability of MLCs but also made the leaf-width smaller.…”

High-risk prostate cancer: is androgen deprivation monotherapy still appropriate?

“…8 The advent of more conformal radiation delivery methods, such as intensity-modulated radiation therapy, may also reduce toxicity, though definitive evidence of enhanced safety of the newer technologies is as yet lacking. 9 The instruments used to assess symptom burden in the study are not as sensitive as more recently developed measures, 10 possibly leading to an underestimation of the impact of radiation related toxicity. In addition, data on some potentially important adverse effects were not reported at all.…”