HJNO Nov/Dec 2023

HEALTHCARE JOURNAL OF NEW ORLEANS I  NOV / DEC 2023 49 Rockne Hymel, III, MD Radiation Oncologist Mary Bird Perkins Cancer Center Terrebonne General excess air in the lungs will move the heart away from the beam of radiation. This is a reproducible technique to minimize poten- tial future cardiac toxicity and is now readily available at most radiation centers through- out the country. Radiation options for breast cancer In the past, radiation most commonly in- volved daily treatments Monday through Friday to the entire breast tissue for five to six weeks, totaling 25 to 30 treatments. In the early 2000s, researchers in the U.K. and Canada decided to see if radiation could be delivered at a higher dose per day over a shorter period of time, known as hypofrac- tionation, with equal efficacy and a similar side effect profile. They found that giving the radiation over either three to four weeks, or 15 to 20 treatments, caused similar side effects compared to the standard longer regimen and improved cosmetic outcome. No increased breast tumor recurrence was found with the shortened regimen. The hy- pofractionated regimen was adopted as the standard of care and has remained as such for about 20 years now. Partial breast radiation Recently, there have been a few evolutions to the possibilities of delivering radiation for breast cancer patients, including one that I am particularly interested in. For some well-selected patients, the treat- ment options can now include standard ra- diation to the entire breast over three or four weeks, radiation to the entire breast over five treatments (search FAST-forward trial for more information), radiation only to the area where the surgery was performed in the breast (partial breast radiation) for just five treatments, or sometimes even no ra- diation at all. In a landmark trial from Florence, Italy, Livi, et al. showed that giving 30Gy, the ra- diation unit of measurement, in five treat- ments to the surgical bed showed a 10-year ipsilateral breast tumor recurrence of just 3.7% versus 2.5% from standard whole breast radiation. Breast-cancer-specific survival was no different between the two groups, and the partial breast arm had sig- nificantly less acute and late toxicity as well as improved cosmetic outcome evaluated by treating physicians. This method is more convenient and has better outcomes than prior efforts at partial breast radiation in the past, some of which used invasive needles, balloon catheters, and twice-daily treatments. While whole breast radiation remains effective and well-tolerated, partial breast radiation is an exciting option for qualifying patients that can offer efficacy, convenience, and an even more well-tolerated treatment. Some women may not experience any no- ticeable toxicities during partial breast ra- diation; those who do mostly experience minor skin irritation over a very small area of the breast, like a small sunburn. Using a CT scan, the radiation oncolo- gist is able to accurately identify the surgi- cal bed in the breast and delineate this in a technique called “contouring,” expand this area by 1cm to account for subclinical/mi- croscopic spread, then additionally expand by 0.5 to 1cm to account for setup variation during treatment delivery to assure accuracy and precision. Essentially, any modern linear accelera- tor is able to safely and effectively deliver this precise treatment. Delivery of each treatment is preceded by a cone-beam CT scan on the linear accelerator to ensure ac- curacy of the target. Partial breast irradiation is generally suit- able for women over 50 years old, BRCA- negative, ER-positive disease less than or equal to 2cm in size, negative surgical mar- gins >2mm, and no lymphovascular invasion. In summary, radiation remains a crucial component of multi-disciplinary breast can- cer care. With modern advances in technol- ogy and treatment delivery along with per- sonalized patient care, radiation oncologists are able to provide more options for patients including partial breast radiation. I believe partial breast radiation is one the of most exciting advances in radiation therapy and breast cancer treatments in the last 20 years. Patients are encouraged to ask questions and discuss extensively with their physi- cians to determine which treatment options are best for them. n REFERENCES 1 Livi, M.; Marrazzo, L.; Saieva, C.; et al. “Acceler- ated Partial-Breast Irradiation Compared With Whole-Breast Irradiation for Early Breast Cancer: Long-Term Results of the Randomized Phase III APBI-IMRT-Florence Trial.” Journal of Clini- cal Oncology 38, no. 35 (Dec. 10, 2020): 4175- 4183. https://ascopubs.org/doi/full/10.1200/ JCO.20.00650 2 National Comprehensive Cancer Network. “NCCN Guidelines.” Accessed September 2023. https://www.nccn.org/guidelines/category_1 Rockne Hymel, III, MD, is the radiation oncologist at Mary Bird Perkins Cancer Center at Terrebonne General in Houma, Louisiana. He earned an under- graduate degree fromLSU,attendedmedical school at LSUHSC in NewOrleans,and completed radiation oncology residency at Medical University of South Carolina in Charleston.He treats all types of cancers and some benign conditions with radiation, including stereotactic body radiation. He is board-certified by the American Board of Radiology. He enjoys com- munity practice and providing high-quality cancer care to the bayou parishes.