News | Radiation Therapy | February 18, 2020

A New Way to Monitor Cancer Radiation Therapy Doses

A new gel-based nanosensor for radiation dose monitoring can be used on skin and is relatively inexpensive

Arizona State University researchers (in collaboration with Banner MD Anderson Cancer Center) have discovered a biocompatible cost-effective hydrogel that can be used to monitor therapeutic doses of ionizing radiation by becoming more pink with increasing radiation exposure

Arizona State University researchers (in collaboration with Banner MD Anderson Cancer Center) have discovered a biocompatible cost-effective hydrogel that can be used to monitor therapeutic doses of ionizing radiation by becoming more pink with increasing radiation exposure. This picture shows a circle of hydrogel that was irradiated on the left half, which is slightly pink; whereas the right half of the gel is not irradiated and remains colorless.

February 18, 2020 — More than half of all cancer patients undergo radiation therapy and the dose is critical. Too much and the surrounding tissue gets damaged, too little and the cancer cells survive. Subhadeep Dutta and Karthik Pushpavanam, graduate students working in the lab of Kaushal Rege, professor at Arizona State University in Tempe, and collaborators at Banner-M.D. Anderson in Gilbert, Ariz., developed a new way to monitor radiation doses that is cost-effective and easy to read. Dutta will present their research on Tuesday, February 18 at the 64th Annual Meeting of the Biophysical Society in San Diego, California.

Radiation therapy directs high energy beams to destroy the genetic material inside cells and prevent them from growing. Typically, a radiation therapy team decides the total dose of radiation, and then divides that total dose over several sessions. The machines and calculations involved are usually spot-on as far as dosages, but sometimes variations, perhaps due to patient movement such as breathing, or in rare instances due to issues with the machine or software, can be causes for error. Monitoring the dose is critical as both overdosing and underdosing can compromise patient safety — too much healthy tissue or too little tumor can be destroyed in the process.

Dutta, Pushpavanam, Rege and colleagues made a hydrogel that can be applied directly to a patient’s skin in order to easily measure radiation doses. Mixed into the hydrogel are gold salts and a few amino acids. Without radiation, the gel is colorless, but as it is exposed to radiation it becomes pink. The color intensity is directly correlated to the amount of radiation. At the end of a treatment, it is painlessly peeled off the skin and the color is measured with a common and relatively inexpensive lab instrument, an absorption spectrometer.

Some dose monitors are currently available for patients. “One looks like a sheet of paper (radiochromic films), but it is sensitive to light and heat, so it must be carefully handled, and requires long processing times. Another is a tiny sensor (NanoDot), which is expensive and requires multiple arrays to cover an area of the skin. Ours can be used directly onto the skin and is relatively inexpensive,” Dutta said.

The gel has performed well in testing and was recently used on canine cancer patients undergoing radiotherapy. “Our next plan is to convert it to an app-based system, where you can take a picture of a gel and that can predict the dose based on programming in the app. It’s just measuring color, which is easy to do,” said Dutta. The team is hopeful that future studies will lead to translation of this technology for use with human patients in the clinic.

For more information: www.biophysics.org/

Related Content

World's largest radiation oncology meeting will offer full conference on interactive platform October 25-28, 2020
News | ASTRO | July 09, 2020
July 9, 2020 — Registration opens today for the American Society for Radiation Oncology's (...
Simulation finds starting at age 30 with MRI and mammography to be the preferred strategy; starting at 25 prevented marginally more deaths, but with more testing and emotional stress

Getty Images

News | Breast Imaging | July 09, 2020
July 9, 2020 — Chest radiation is used to treat children with Hodgkin and non-Hodgkin lymphoma as well as lung metast
At the American Association of Physicists in Medicine (AAPM) 2019 meeting, new artificial intelligence (AI) software to assist with radiotherapy treatment planning systems was highlighted. The goal of the AI-based systems is to save staff time, while still allowing clinicians to do the final patient review. 
Feature | Treatment Planning | July 08, 2020 | By Melinda Taschetta-Millane
At the American Association of Physicists in Medicine (AAPM) 201
 Many patients with severe coronavirus disease 2019 (COVID-19) remain unresponsive after surviving critical illness. Investigators led by a team at Massachusetts General Hospital (MGH) now describe a patient with severe COVID-19 who, despite prolonged unresponsiveness and structural brain abnormalities, demonstrated functionally intact brain connections and weeks later he recovered the ability to follow commands

Getty Images

News | Coronavirus (COVID-19) | July 08, 2020
July 8, 2020 — Many patients with severe coronavirus disease 2019 (...
Changes outlined in new draft U.S. Preventive Services Task Force (USPSTF) lung cancer screening recommendations will greatly increase the number of Americans eligible for screening and help medical providers save thousands more lives each year.

Image courtesy of Cerner

News | Lung Imaging | July 08, 2020
July 8, 2020 — Changes outlined in new draft U.S.
Radiotherapy has been used to treat cancers for more than a century and continues to be utilized in cancer treatment plans today. Since the introduction of radiotherapy, clinicians have been working tirelessly to further refine treatments to better target cancer.
Feature | Radiation Therapy | July 06, 2020 | By Yves Archambault
Everything has room for improvement, right? Right. When it comes to cancer care, it is no different.
Proton therapy has evolved, and future predictions include smaller systems, more sophisticated proton dosimetry and devices that manipulate the proton beam
Feature | Proton Therapy | July 06, 2020 | By Minesh Mehta, M.D.
The field of proton...
Researchers reviewed results of prostate biopsies on over 3,400 men who had targets identified on prostate MRI and found that the positive predictive value of the test for prostate cancer was highly variable at different sites
News | Prostate Cancer | July 01, 2020
July 1, 2020 — Prostate MRI is an emerging technology used to identify and guide treatment for...