Highlights from the 2015 HOPA Preconference Session Radiation for the Oncology Pharmacist
Megan V. Brafford, PharmD BCOP
Clinical Oncology Pharmacy Specialist
Baptist Health Lexington
Lexington, KY
One of the featured preconference sessions at HOPA’s 11th annual conference was Radiation for the Oncology Pharmacist, which provided a wonderful overview of how to select the appropriate candidate for radiation therapy after a cancer diagnosis, specifically in the breast and prostate cancer populations. Education was also provided on the different preventive and treatment regimens a pharmacist can recommend to help a patient manage specific radiation-induced toxicities.
The goal of radiation treatment is to destroy cancer cells while pre- serving the integrity of normal tissues within and immediately adjacent to the radiation treatment field. The two major categories of radiation therapy are external beam radiation, which delivers radiation by a ma- chine outside of the body, and brachytherapy, which delivers radiation by radioactive material placed in the body near or within the tumor itself. Advances in radiation therapy now allow for better visualization of the patient’s anatomy to more clearly focus the radiation, improved manipulation of necessary doses, less of an exit dose with proton therapy, and more precise alignment of the patient for daily treatments. The presentation by radiation oncologist Dr. Karen E. Hoffman included multiple images to help the audience to truly envision what a patient would experience throughout his or her time in radiation therapy—from the first day of stimulation, through daily visits, to follow-up care after radiation is complete.
In breast cancer patients, radiation therapy can be utilized after breast- conserving surgery and is administered over the whole breast. Radiation therapy is also used in select women who have clinically significant risks of recurrence after a mastectomy. Radiation therapy can improve both local cancer control and breast cancer survival. Radiation therapy is a treatment option for the majority of men with localized prostate cancer. Dr. Hoffman said dose-escalated radiation therapy improves prostate cancer control compared with standard-dose radiation. The addition of androgen deprivation therapy to external beam radiation therapy improves prostate cancer survival for men whose cancer has unfavorable prognostic factors.
The development of radiation-induced toxicity depends on multiple factors, including the area of the body treated, dose given per day, total dose given, patient’s performance status, and concomitant therapy. Acute toxicity can occur hours to weeks after radiation exposure and lasts up to 3 months after receiving therapy. Primary acute toxicities include radiation dermatitis, otitis externa, serous otitis media, osteoradionecrosis, xerostomia, thick saliva, dysgeusia, mucositis, nausea/ vomiting, diarrhea, proctitis, acute cystitis, and pneumonitis. Chronic toxicities usually present 6 or more months after a course of radiation. Potential chronic toxicities include oropharynx issues, cardiac toxicity, pulmonary fibrosis, radiation necrosis, cognition issues, infertility, and development of a secondary malignancy. Each of these toxicities can negatively affect a patient’s quality of life and potentially duration of life. Pharmacologic strategies are available to manage many acute radiation toxicities and some chronic radiation toxicities. It is essential for pharmacists to be involved in educating patients who are receiving radiation therapy about the potential side effects and risks of treatment as well as assisting providers in management strategies to prevent and treat these radiation-induced toxicities.