Welcome to 2018! This is an exciting, transformative time in breast cancer treatment, with advances neoadjuvant chemotherapy, wire-free tumor localization, and more tools for post-surgical radiation. Last year the TRIUMPH-T Trial for 2-day brachytherapy, completed patient enrollment and will begin to report out interim results as early as March 2018. Trial investigator Atif J. Khan, MD provides a snapshot of this exciting trial.
What were the reasons for wanting to pursue a potential 2-day course of brachytherapy?
Partial Breast Irradiation as a whole is maturing now and the data is becoming very compelling, demonstrating the equivalency of PBI to whole breast irradiation (WBI).
Brachytherapy has been the original and, to date, the best studied approach to delivering partial breast irradiation. Historically, partial breast irradiation was delivered in 4 to 5 days, twice a day. This meant 8 to 10 trips to the treatment center for the patient. While it was more convenient than traditional WBI we had parallel literature developing with Intra-Operative Radiation Therapy (IORT) where the radiation treatment is given all in one shot while the patient is still in the OR.
This has strong appeal, but we see a problem with giving treatment before fully characterizing the patient’s risk. We don’t know the status of lymph nodes and margins and we are giving a treatment that is dependent on the outcome of what is reported in the pathology report.
These downsides were enough to disqualify IORT treatment in our minds as a good treatment option. So we asked the question, “what if we could mimic the convenience of IORT without compromising the right patient selection and still compress the radiation treatment schedule to 3 doses?” The result – the TRI-fraction Radiotherapy Minimize Patient Hospital Trips or TRIUMPH-T trial.
What was the primary objective of the trial?
The primary end point of the study was to evaluate the toxicity and safety of compressing the radiation treatment. We had little reason to believe that tumor control would be any different than the 5 day course of treatment but we wanted to make sure that the effect of the new schedule on the normal tissue would be tolerable and we would not see any serious side effects or that they would be similar to what we observe in 4-5 day course of treatment.
Based on early observations, we have not seen the types of toxicities we were monitoring for – in that regard the trial has been a success and we look forward to reporting the results.
What was the dosing used in TRIUMPH-T and how was that dose determined?
To develop the rather complex model for dosing we consulted a renowned expert in the radiobiology of brachytherapy and breast cancer, Professor Roger Dale, Professor of Cancer Radiobiology in the Faculty of Medicine at Imperial College, London. The fractionation schedule is three fractions of 7.5 gray for a total of 22.5 gray. This brachytherapy dose is equivalent to the 50 gray received in a full course of WBI with 25 fractions.
What type of reaction did you see from patients to the concept of a 2-day radiation treatment following lumpectomy?
I can enthusiastically say that the patients in the trial loved the treatment schedule. It was less disruptive to their lives and they could get back to their routine quickly. We place the device on day one and deliver the first fraction. The patient comes back the next day for two fractions, the device is pulled and the treatment is done. It is that simple. They really liked the fact they only had the device in the breast overnight. Overall their collective experiences were very positive.
Do you see a 2-day treatment having an impact on the number of women choosing breast conservation vs. mastectomy?
This is hard to say, but I do believe in certain parts of the country, and even around world, where radiation facilities and resources are scarce and where there are large geographic distances between treatment facilities, this can potentially be a game changer. It gives women an option to receive breast conservation therapy instead of a mastectomy since the treatment is simply two days and just an overnight stay.
How many women were enrolled in the trial and when can the breast cancer community expect to see data analysis?
We enrolled 200 women over a three-year period with the last patient enrolled in late summer 2017. The trial investigators will follow the participants for a minimum of two years after the last enrolled patient – so until the fall of 2019.
We anticipate that the first paper with interim results will be submitted in March 2018 and hopefully be in print by the summer of 2018.
Dr. Khan is Associate Attending and Director of Breast Cancer Research, Department of Radiation Oncology at Memorial Sloan Kettering Cancer Center. He is principal investigator of three breast fractionation trials. He has authored or co-authored several papers and book chapters and serves as an oral examiner for the American Board of Radiology, the certifying body for radiation oncology trainees.
Participating institutions in the TRIUMPH-T Trial: Rutgers Cancer Institute of New Jersey (New Brunswick, NJ), Arizona Breast Cancer Specialists (Scottsdale, AZ), William Beaumont Hospital Radiation Oncology (Royal Oak, MI), Bryn Mawr Hospital Cancer Center (Bryn Mawr, PA), University of California San Diego Health System (La Jolla, CA), Huntsman Cancer Institute, Cleveland Clinic, and 21st Century Oncology of Michigan (Farmington Hills, MI).