Nuclear Medicine & Radiation Therapy

Biography

Biography: Heming Lu

Abstract

Intensity-modulated radiation therapy (IMRT) has now replaced conventional radiation therapy and three-dimensional radiation therapy and become a standard treatment technique for head and neck cancer. This technique provides adequate target coverage while maintaining steep dose gradients at the border between the targets and adjacent normal tissues. However, significant anatomic changes may occur throughout the entire treatment course. These changes include the shrinkage of the primary disease and metastatic lymph nodes, external contour because of significant weight loss and displacement/size of the normal structures. As a consequence, the initial planning based on pretreatment condition may not truly reflect the dosimetric variations during the course of IMRT. Thus adaptive radiation therapy (ART), a plan modification and implementation according to tumor response and anatomic changes of normal structures, becomes particularly important. In recent years, many researchers have focused on ART for head and neck cancer patients. Results from dosimetric studies suggest that the initiation of ART during fractionated IMRT provides various benefits, particularly in preventing overdose to the critical structures. The feasibility of ART in clinical practice, both in online and in offline settings, has been broadly reported in the literature. However, many questions remain unanswered: Who would benefit most for ART? What is the optimal timing and frequency to perform ART? Whether ART re-planning can transfer into clinical benefits? Mature outcomes from basic and clinical researches will be necessary to appropriately mold ART into a future treatment standard.