Health: Hadrontherapy, from ENEA and CNAO innovative technologies for more effective oncological treatments

More and more reliable and personalised oncological treatments thanks to new smart and compact devices capable of precisely measuring the radiation dose to be used in hadrontherapy for the treatment of tumors, which specifically destroys the tumor mass while preserving healthy tissues.

This is what emerges from a study carried out by a team of researchers from ENEA and the National Center for Oncological Hadrontherapy (CNAO), published in the journal Radiation Measurements^[1]. ENEA has also designed and created a prototype of a compact optical system capable of "reading" the information on the stored dose, even multiple times and without deleting it, so as to be able to repeat, compare and check the results in different laboratories and with different measurement systems.

Specifically, the study demonstrates that solid-state radiation detectors based on lithium fluoride (LiF), a material sensitive to ionizing radiation (X-rays, gamma rays, electrons, protons, ions, etc.), can be effectively used in clinical dosimetry for the treatment of tumors. The results were obtained by exploiting a light emission phenomenon, known as radiophotoluminescence, characteristic of electronic defects, called color centers, which form in LiF when ionizing radiation passes through it. The innovation achieved in the TECHEA^[2] project consists in the technique of measuring the dose of ionizing radiation through a blue laser source that "excites" the radiophotoluminescence, properly collected with a phototube and amplified with electronic techniques^[3] developed by the Physical Technologies and Safety Division of ENEA.

LiF is equivalent to human tissue in its interaction with radiation and has other interesting characteristics such as manageability, compactness and insensitivity to ambient light, which allow to simplify and make more reliable the procedures for measuring the radiation dose required by the medical physicist. Furthermore, this type of detector is reusable, does not require electrical power and can be used both in phantoms and for patient monitoring.

The dosimetric characterization study of the detectors was carried out in a treatment room at the CNAO Foundation, by irradiating the samples with high-energy clinical proton beams produced by the CNAO synchrotron and subjected daily to strict quality controls by the medical physics team of the Foundation itself.

“The multidisciplinary nature of this research in which photonics, spectroscopy, ionizing radiation and materials science deal with the needs of medical physics to address the challenge of clinical dosimetry in hadrontherapy, requires that the rapid progress achieved so far be further developed, taking advantage of the use of the most advanced technologies, in the interest of the patient and for the benefit of health”, explain Massimo Piccinini, ENEA researcher at the Micro and Nanostructures for Photonics Laboratory, and Maria Aurora Vincenti, head of the same laboratory.

“This study represents a virtuous example of synergy between a prestigious research center, such as ENEA, and an equally excellent center for the treatment of cancer patients using hadrontherapy (protons and carbon ions), such as CNAO, which for over ten years has been committed to research and technological innovation, for increasingly effective and precise treatments”, says Mario Ciocca, medical physicist, head of the Medical Physics Unit of the CNAO Foundation in Pavia.