PO08: Potential Innovations in Brachytherapy

Abstract

Optimizing brachytherapy applicability requires circumventing shape size homogeneity limitations as well as allowing concomitant utilization of other modalities especially hyperthermia and nanoparticles. <h3>Material and Methods</h3> For more than a decade, strategies continue to be developed to produce applicators that allow using BTX in clinical situations in which local cancer control is crucial for survival and symptomatic relief. This often involves memory shaped material especially nitinol, novel isotopic states for clinical use and multiple materials. These are to be deployed in naturally occurring or iatrogenic intracavitary sites.. Hyperthermia which has proved effective could be induced multiple ways including adding voltage to the nitinol core, circulating water baths, and externally via ultrasound and radio frequencies. The former allows the hyperthermia applications to be intermittent or continuous although at this time the optimal timing is unknown. In the past quality control of hyperthermia has been a challenge but the use of multiple techniques with feedback can improve hyperthermia homogeneity; as well as the potential use of diffusing nano particles which could incorporate chemotherapy, immunotherapy or even metal particles to generate heat. Continuously emitting radiation sources LDR or vLDR are believed by some investigators to have a biological advantage when compared to HDR based on higher LET and RBE and lower OER; individual clinicians will select the modality for each situation. Because the isotope occupies a much larger volume the Dmax is lower when compared to seeds and efforts are ongoing to further improve the dose gradient.. Since patients with recurrent GBM's have demonstrated short term improvement with both hyperthermia and brachytherapy as with a Gliosite; meeting the challenge of hyperthermia delivery and quality control would be reasonably expect to improve outcomes. In other cancers in which local recurrence/persistence is a clinical issue such a breast cancer and other tumorectomies, bone metastasis, tracheobronchial, gynecological and GI tract warrants further resource utilization. Selective treatment of vascular diseases to prevent restenosis and potentially to improve resect ability in selective sites such as pancreatic cancers may be too provocative. <h3>Results</h3> Multimodality applicator devices have been designed for multiple sites including the brain, bone lesions, GI,thoracic post resection including bi/trifurcating devices as well as multiple patents have been filed and most have already been secured. Monte Carlo calculations have demonstrated feasibility of this strategy. <h3>Conclusion</h3> This work in progress has demonstrated feasibility of using devices that optimize Brachytherapy and offer potential for improved local cancer control in many situations.