The Radiation Therapy Department at the Tom Baker Cancer Centre (TBCC), under the directorship of an experienced radiation oncologist/world-class breast researcher and his fourth-year resident, put forth to the Health Research Ethics Board Alberta-Cancer Care (HREBA-CC) Accelerated Partial Breast Irradiation Using Five Daily Fractions: A Single Arm, Phase II, Prospective Cohort Study to Examine Cosmetic Outcomes and Toxicity (the ACCEL Trial) for review and approval.

Prior to the submission of the protocol, an experienced clinical research radiation therapist, who was a past research grantee and had prior publications, was involved with the creation of all the HREBA-CC approved documents. That early participation/teamwork created the basis for a rock-solid ACCEL research team. This team included all of the breast radiation oncologists, radiation therapists, dosimetrists, medical physicists and radiation therapy (RT) nurses.

In March 2016, HREBA-CC gave full board approval for the ACCEL Trial. The team had expected that this would occur, so a workshop was scheduled at the TBCC in April 2016 for the ACCEL Trial with the aim to educate and train all of the health-care professionals for each specific area/task. This was done because there would be two new community cancer centres, Red Deer Cancer Centre (RDCC) and the Jack Ady Cancer Centre (JACC) in Lethbridge, that would not only open the ACCEL Trial in their respective departments, but would also establish a research department. The ACCEL workshop was facilitated by the research radiation therapist and the radiation oncologist (principal investigator).

The workshop was successful, and the first official partial breast patient was recruited at the TBCC in May 2016. The protocol defines the criteria for eligibility for the ACCEL Trial patients. The process that was used is described below.

During the breast consultation with the patient, the radiation oncologist provided an introduction to the ACCEL Trial and described the risks and benefits of whole breast RT versus the partial breast RT. At the conclusion of the consultation, the patient was given the consent form package to take home and read. Prior to contacting the referred patient, the research radiation therapist verified 25 parameters that determined eligibility for the ACCEL Trial. The research radiation therapist called the potential ACCEL patient, explained the ACCEL Trial and provided a verbal descriptive picture to illustrate the radiation treatments.

Once verbal consent was obtained, the research therapist scheduled the consent process one hour before the CT simulation. The following tasks were completed during this process:

• PowerPoint presentation specifically for ACCEL Trial patients.
• Research radiation therapist encouraged Q&A discussion regarding the Trial before the patient signed the consent form.
• Authorization from the patient to palpate (touch) along seroma (surgical site plus 7 mm margin) incision to assess the extent of fibrosis.
• Two digital photographs were taken of both breasts as per protocol and for future cosmesis evaluation.
• Both the patient and the research radiation therapist performed a cosmetic assessment of the affected breast as compared to the contra-lateral breast.
• When the consent process achieved all of the tasks as outlined above, the patient was taken to the CT simulator. The patient underwent a CT scan of the affected breast and contra-lateral breast. This 3D data was used to plan the dosimetric parameters to the prescribed treatment volume.

Once the consent process and CT simulation had been completed, the next step in the ACCEL Trial was for the research radiation therapist to download and secure the digital clinical photographs in the Research Electronic Data Capture (REDCap) database. This was created by the University of Calgary Clinical Research Unit (CRU). All the digital pictures were resized and labelled to be identified through a numbering system (as per protocol) to ensure the patient’s confidentiality was maintained.

The cosmetic worksheet the patient and research radiation therapist completed during the consent process was entered into the patient’s file in REDCap. All information was secured and all researchers in the ACCEL Trial abide by the good clinical practice (GCP) standards.

When the ACCEL patient arrived for radiation therapy, the seroma received a daily tumor dose (DTD) of 5.4 Gy per treatment (TTD=total tumor dose of 27 Gy/5 fractions). The radiation oncologist saw the patient once during their five radiation treatments and at the patient’s first follow-up appointment 6-8 weeks after the last treatment. The ACCEL patient is seen at one year and finally at two years post-treatment. Completion of the ACCEL Trial redirects the follow-up care to the patient’s family physician for annual assessments and mammography.

The ACCEL Trial started in May 2016 and concluded in October 2019. 294 patients were recruited for the ACCEL Trial. To date, this is an effective alternative to the standard whole breast RT. However, there is one caveat: this is only applicable to those with very early staged breast cancer (no lymph node involvement), which statistically contributes to ~30% of the breast patient population.

The next step for patients is to attend the follow-up appointments so that both the clinical assessment by the radiation oncologist and radiation therapist can be completed as per the ACCEL Trial protocol.

The ACCEL Trial is a success story for the Radiation Therapy Department at the TBCC because of the teamwork and support of all the radiation therapists and the management team. This research was done with the assistance of many, many healthcare professionals (some from the ACMDTT) and other professional groups.

The future of partial breast RT is promising, as much of the radiation oncology world already uses this treatment. There are discussions of an upcoming Canadian research trial that will compare partial breast to whole breast on a national stage.