Benjamin Smith, MD

2012-2013 BCRF Project(s):
Conquer Cancer Foundation of ASCO 2011 Career Development Award

Every year in the United States, over 100,000 women receive radiation therapy after a lumpectomy for breast cancer. Radiation therapy treats cancer cells that may remain in the breast after a lumpectomy, and as a result it substantially lowers the chance that the cancer will come back in the breast and also improves long-term survival.

The standard schedule for administration of radiation therapy used in the United States consists of about six to six and a half weeks of radiation therapy administered on a daily basis, Monday through Friday. The first five weeks of radiation are administered to the entire breast and the last one to one and a half weeks are administered as a "boost" that is only given to the part of the breast where the cancer started.

Recent evidence from randomized, clinical trials conducted in Canada and the United Kingdom has suggested that a shorter radiation treatment schedule yielded similar side effects and cure rates compared to treatment schedules similar to those used most commonly in the United States. However, these trials were limited in that a tumor bed boost was often not used and many of the patients did not receive chemotherapy.

Dr. Smith's group is interested in learning more about the use of shorter treatment schedules in the treatment of breast cancer after a lumpectomy, particularly in patients who need a tumor bed boost and who may receive chemotherapy. They have started a randomized clinical trial that compares a four-week radiation treatment schedule to a six week radiation treatment schedule. All patients in this trial receive a boost and patients who receive chemotherapy either before or after surgery are eligible to participate. They aim to enroll approximately 200 patients over two years. Thus far, 112 patients have enrolled in the study.

Dr. Smith's group is most interested in learning about how patients feel about the appearance of their treated breast compared to the untreated breast. Physicians will also rate the appearance of the treated breast. Patients will be followed to make sure that the chances of recurrence are similar for both treatment schedules. There will also be a component of the study that will seek to learn more about whether variations in a specific gene correlate with risk of radiation side effects. Another component of the study will seek to determine if there are parameters that can be determined at the time of radiation treatment planning that predict for side effects.

If this trial can confirm that the side effects and tumor control rates for the four week radiation treatment schedule are similar to the side effects and tumor control rates for the six week radiation treatment schedule, the implication would be that the majority of women who need radiation after a lumpectomy could receive the shorter treatment schedule, which would enhance convenience of treatment for patients and lower overall cost of treatment. However, if Dr. Smith's team finds that the four-week radiation treatment schedule less effective, this would also be important information that would discourage adoption of the shorter radiation treatment schedules which are currently advocated based on results from the recently reported trials from Canada and the United Kingdom.

Mid-year Progress: Dr. Smith's team continues to conduct a randomized trial comparing a shorter course of breast radiation therapy to the standard six-week course of breast radiation therapy. Their protocol has been open for almost two years, and so far approximately 170 patients have enrolled. The study intends to determine if the shorter course breast radiation is as good as the longer course with respect to the way the breast looks and feels to the patient three years after treatment. As patients are still being enrolled on this study, Dr. Smith's team does not yet have any data to report. Nevertheless, patient accrual is going well, and the researchers are gathering all the data to answer their study question.

Bio:
Dr. Smith is an Assistant Professor of Radiation Oncology (tenure-track) at MD Anderson and a board-certified radiation oncologist with clinical and research expertise in cancer treatment and health services research. He is currently vice-chair of the American Society for Radiation Oncology (ASTRO) guidelines subcommittee and has led ASTRO's efforts to develop evidence-based guidelines on accelerated partial breast radiation and fractionation of whole breast irradiation. He has authored or co-authored 37 peer-reviewed original research papers, including several articles featured in high profile journals such as the Journal of the National Cancer Institute and the Journal of Clinical Oncology.

In addition, Dr. Smith maintains a busy portfolio of health services research projects which broadly focus on leveraging existing health claims datasets to elucidate the use, effectiveness, toxicity, and cost-effectiveness of various radiation modalities commonly used in the treatment of cancer. This research is funded in part by a multi-institutional, multi-investigator grant from the Cancer Prevention and Research Institute of Texas to conduct comparative effectiveness research on cancer in Texas. As a radiation oncologist, Dr. Smith specializes in the care of women with breast cancer, and has a particular clinical interest in the care of elderly women with this disease.